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19-0657; Rev 0; 10/06
Automotive Micropower Linear Regulators with Supervisor
General Description
The MAX6765-MAX6774 are low-quiescent-current, highvoltage linear regulators that operate from 4V to 72V and deliver up to 100mA of load current. These low-power devices consume only 31A of quiescent current, making them ideal for always-on automotive modules. These devices are offered with fixed standard output options of 5.0V, 3.3V, 2.5V, and 1.8V, or can be adjusted from 1.8V to 11V with two external resistors. The MAX6765-MAX6774 feature a push-pull or opendrain, active-low RESET output with either fixed or adjustable thresholds. Whenever the regulator's output falls below the reset threshold, the RESET output asserts and remains asserted for at least the minimum reset timeout period after the output voltage exceeds its threshold. The minimum reset timeout period is offered with fixed values from 75s to 200ms or can be adjusted externally with a small capacitor. These devices provide three regulator enable modes to accommodate several power-on schemes. The MAX6765/MAX6766/MAX6769/MAX6770/MAX6773/ MAX6774 feature a single traditional enable input (ENABLE) to turn on and off the regulator. The MAX6771/MAX6772 provide dual enable inputs (ENABLE1 and ENABLE2) to turn on and off the regulator either through an ignition switch or a bus transceiver. The MAX6767/MAX6768 provide a hold input (HOLD) in addition to the enable input to allow for the implementation of a self-holding circuit without requiring external components. Setting HOLD low after enabling the regulator forces the regulator to remain on even if ENABLE is subsequently set low. Releasing HOLD shuts down the regulator. The MAX6773/MAX6774 also include a watchdog input that monitors a pulse train from the microprocessor (P) and generates a reset pulse if the watchdog input remains high or low for a duration longer than the 1.6s (typ) watchdog timeout period. The MAX6765-MAX6774 are available in a small, thermally enhanced 3mm x 3mm TDFN package that can dissipate up to 1.951W, thereby supporting continuous regulator operation during high ambient temperatures, high battery voltage, and high load-current conditions. The MAX6765-MAX6774 are fully specified for a -40C to +125C operating temperature range.
Features
Low 31A Quiescent Current 4V to 72V Wide Input Voltage Range 100mA Output Current Capability Dropout Voltage of 620mV with 5V Output at 100mA Fixed Output-Voltage Options: 5V, 3.3V, 2.5V, and 1.8V Adjustable Output Voltages from 1.8V to 11V Open-Drain or Push-Pull RESET Output Fixed or Capacitor-Adjustable Reset Timeouts Small, Thermally Enhanced 1.9W, 3mm x 3mm TDFN Package Overtemperature and Short-Circuit Protection Fully Specified from -40C to +125C
MAX6765-MAX6774
Ordering Information
PART MAX6765TT_D_+* MAX6766TT_D_+* TEMP RANGE PINPACKAGE PKG CODE T633-2 T633-2
-40C to +125C 6 TDFN-EP** -40C to +125C 6 TDFN-EP**
Ordering Information continued at end of data sheet. The first "_" is a placeholder for the voltage output and reset threshold. The 2nd "_" designates the fixed reset-timeout option. See Tables 1 and 2 for details. For example, the MAX6765TTLD4 has a 5V output, a reset threshold of 4.65V, and a 200ms typical reset timeout. +Denotes lead-free package. *Future product--contact factory for availability. **EP = Exposed paddle. For tape-and-reel orders add a "T" after the "+" symbol to complete the part number. Tape-and-reel orders are available in 2.5k increments. Nonstandard versions require a 10k minimum order quantity.
Pin Configurations
RESET 4 3 ENABLE OUT
TOP VIEW
6
MAX6765 MAX6766
Applications
Automotive Industrial Telecom
Typical Application Circuit and Selector Guide appear at end of data sheet.
+ 1 IN 2 GND
TDFN
Pin Configurations continued at end of data sheet. 1
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
ABSOLUTE MAXIMUM RATINGS
(All pins referenced to GND, unless otherwise noted.) VIN ..........................................................................-0.3V to +80V OUT ................................................-0.3V to min (12V, IN + 0.3V) ENABLE, ENABLE1, ENABLE2 .....................-0.3V to (IN + 0.3V) RESET (open-drain output), TIMEOUT, WDI, RESETIN, SET ......................................................-0.3V to 12V RESET (push-pull output), HOLD ..............-0.3V to (OUT + 0.3V) Maximum Current (all pins except IN and OUT).................50mA Continuous Power Dissipation (TA = +70C) 6-Pin TDFN 3mm x 3mm (derate 23.8mW/C above +70C) ...........................1904.8mW 8-Pin TDFN 3mm x 3mm (derate 24.4mW/C above +70C) ...........................1951.2mW Operating Temperature Range .........................-40C to +125C Junction Temperature ......................................................+150C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VIN = 14V, CIN = 0.1F, COUT = 10F, TA = TJ = -40C to +125C, unless otherwise noted. Typical values are at TA = TJ = +25C.) (Note 1)
PARAMETER Supply Voltage Range SYMBOL VIN ILOAD = 0 Supply Current (MAX6765-MAX6772) (Note 2) ILOAD = 50mA ILOAD = 100mA, VIN = 14V ILOAD = 0, VIN = 42V ILOAD = 10mA, VIN = 42V ILOAD = 0 ILOAD = 50mA ILOAD = 100mA ILOAD = 0, VIN = 42V ILOAD = 10mA, VIN = 42V Shutdown Supply Current ISHDN ENABLE , ENABLE1, ENABLE2 = GND L/M, ILOAD = 1mA L/M, 1mA ILOAD 100mA, VIN = 11V T/S, ILOAD = 1mA Output Voltage VOUT T/S, 1mA ILOAD 100mA, VIN = 9.3V Z/Y, ILOAD = 1mA Z/Y, 1mA ILOAD 100mA, VIN = 8.5V W/V, ILOAD = 1mA W/V, 1mA ILOAD 100mA, VIN = 7.8V Adjustable Output Voltage Range SET Threshold Voltage (MAX6767-MAX6774) Dual ModeTM SET Threshold VOUT VSET ILOAD = 1mA SET rising SET falling 4.925 4.850 3.251 3.201 2.463 2.425 1.773 1.746 1.8 1.20 1.233 116 58 mV CONDITIONS MIN 4 31 35 37 35 37 38 42 44 42 44 3.3 5 5 3.3 3.3 2.5 2.5 1.8 1.8 TYP MAX 72 45 50 55 50 55 50 55 60 55 60 7 5.075 5.150 3.350 3.399 2.538 2.575 1.827 1.854 11.0 1.26 V V V A A UNITS V
Supply Current (MAX6773/MAX6774) (Note 2)
A
Dual Mode is a trademark of Maxim Integrated Products, Inc.
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Automotive Micropower Linear Regulators with Supervisor
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 14V, CIN = 0.1F, COUT = 10F, TA = TJ = -40C to +125C, unless otherwise noted. Typical values are at TA = TJ = +25C.) (Note 1)
PARAMETER SET Input Current (MAX6767-MAX6774) SYMBOL ISET CONDITIONS VSET = 1.5V, VIN = 11V L/M, 5V output option, ILOAD = 10mA Dropout Voltage (Note 3) VDO L/M, 5V output option, ILOAD = 50mA L/M, 5V output option, ILOAD = 100mA T/S, 3.3V output option, ILOAD = 100mA Guaranteed Output Current (Note 4) Output Current Limit Thermal-Shutdown Temperature Thermal-Shutdown Hysteresis Line Regulation Load Regulation (MAX6767-MAX6774) Power-Supply Rejection Ratio Startup Response Time Output Overvoltage Protection Threshold Output Overvoltage Protection Maximum Sink Current Input Low Voltage Input High Voltage ENABLE, ENABLE1, ENABLE2 Input Pulldown Current VIL HOLD Input Threshold Voltage VIH HOLD Input Pullup Current RESET OUTPUT L M T RESET Threshold SET = GND, RESET falling S Z Y W V 4.500 4.250 2.970 2.805 2.250 2.125 1.620 1.530 4.625 4.375 3.053 2.888 2.313 2.188 1.665 1.575 4.750 4.500 3.135 2.970 2.375 2.250 1.710 1.620 V 1.8V VOUT 11V HOLD is internally pulled up to OUT VIL VIH PSRR tSTART OVTH 6.5V VIN 72V, ILOAD = 1mA IOUT = 1mA to 100mA, VIN = VOUT(NOM) + 6V ILOAD = 10mA, fIN = 100Hz, 500mVP-P From ENABLE high to OUT, ILOAD = 100mA ISINK = 1mA (from OUT) OUT = OUT(NOM) x 1.15 1.07 x VOUT 5 70 180 1.1 x VOUT 10 1.13 x VOUT Output shorted to GND, VIN = 14V 100 150 250 160 20 1 1.5 MIN -100 60 300 620 866 TYP MAX +100 130 630 1200 1600 mA mA C C % % dB s V mA mV UNITS nA
MAX6765-MAX6774
LOGIC INPUT (ENABLE, ENABLE1, ENABLE2, HOLD) ENABLE, ENABLE1, ENABLE2 ENABLE, ENABLE1, ENABLE2 ENABLE, ENABLE1, ENABLE2 are internally pulled down to GND 1.8V VOUT 11V OUT 0.4 1.8 1.4 0.6 0.4 V A 0.4 V V A
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 14V, CIN = 0.1F, COUT = 10F, TA = TJ = -40C to +125C, unless otherwise noted. Typical values are at TA = TJ = +25C.) (Note 1)
PARAMETER RESET Threshold (Adjustable Output Voltage) RESETIN Input Current SYMBOL CONDITIONS L/T/Z/W, SET = resistive divider, RESET falling M/S/Y/V, SET = resistive divider, RESET falling RESETIN = GND or 12V VTH = 87.5% of VSET (M/S/Y/V), RESET falling RESETIN Threshold VTH = 92.5% of VSET (L/T/Z/W), RESET falling OUT to RESET Delay RESETIN To RESET Delay VOUT falling RESETIN falling D0 RESET Timeout Period (TIMEOUT Connected to OUT) D1 VOUT rising D2 D3 D4 TIMEOUT Ramp Current TIMEOUT Ramp Threshold RESET Output-Voltage Low (Open Drain or Push-Pull) RESET Output-Voltage High (Push-Pull) RESET Open-Drain Leakage Current Watchdog Minimum Input Pulse Watchdog Input Low Voltage Watchdog Input High Voltage Watchdog Input Low Voltage Watchdog Input Current Watchdog Timeout Period tWDI VIL VIH VIL IWDI tWD VOUT 1.8V, ISINK = 50A, RESET asserted VOL VOUT 1.8V, ISINK = 3.2mA, RESET asserted VOUT 1.8V, ISOURCE = 250A, RESET not asserted RESET not asserted, RESET = 12V 1.8V VOUT 11V 1.8V VOUT 11V 1.8V VOUT 11V 1.8V VOUT 11V WDI = 0V or WDI = 12V -1 1.12 1.6 VOUT - 0.4V 0.4 +1 2.08 1 0.4 0.8 x VOUT 100 2.187 8.75 35 140 800 1.160 1.118 1.147 0.3 35 75 3.125 12.5 50 200 1000 1.22 4.063 16.25 65 260 1200 1.259 0.3 V 0.4 V nA s V V V A s nA V ms 1.176 s s s MIN VOUT x 0.9 VOUT x 0.85 -100 1.057 1.085 TYP VOUT x 0.925 VOUT x 0.875 MAX VOUT x 0.950 V VOUT x 0.900 +100 1.112 V nA UNITS
VOH
Note 1: Production tested at TA = +25C. Overtemperature limits are guaranteed by design. Note 2: Device tested at internally set voltage. Note 3: Dropout voltage for L/M versions is defined as (VIN - VOUT) when VOUT equals 98% of the nominal value of VOUT when VIN = 11V. For T/S versions, dropout voltage is defined as (VIN - VOUT) when VOUT equals 98% of the nominal value of VOUT when VIN = 9.3V. Note 4: Observe the absolute maximum power dissipation limits.
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Typical Operating Characteristics
(VIN = 14V, COUT = 10F, CIN = 0.1F, TA = +25C, unless otherwise noted.)
SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE
MAX6765 toc02
SUPPLY CURRENT vs. INPUT VOLTAGE
42 40 SUPPLY CURRENT (A) 38 36 34 32 30 28 26 24 4 12 20 28 36 44 52 60 68 INPUT VOLTAGE (V) ILOAD = 0 VOUT = 3.3V LIMITED BY POWER DISSIPATION ILOAD = 100mA
MAX6765 toc01
SUPPLY CURRENT vs. TEMPERATURE
47 45 43 SUPPLY CURRENT (A) 41 39 37 35 33 31 29 27 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) ILOAD = 0 ILOAD = 1mA ILOAD = 100mA ILOAD = 50mA VOUT = 5V 5.0 SHUTDOWN SUPPLY CURRENT (A) 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0
-40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C)
SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE
6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 4 12 20 28 36 44 52 60 68 INPUT VOLTAGE (V)
MAX6765 toc04
NORMALIZED RESETIN THRESHOLD VOLTAGE vs. TEMPERATURE
1.004 1.003 1.002 1.001 1.000 0.999 0.998 0.997 0.996 0.995 0.994 0.993 0.992 TEMPERATURE (C) 600 550 500 450 400 350 300 250 200 150 100 50 0 0
MAX6765 toc05
DROPOUT VOLTAGE vs. LOAD CURRENT
VOUT = 5V
MAX6765 toc06
NORMALIZED RESETIN THRESHOLD VOLTAGE
-40 -25 -10 5 20 35 50 65 80 95 110 125
DROPOUT VOLTAGE (mV)
SUPPLY CURRENT (A)
10 20 30 40 50 60 70 80 90 100 LOAD CURRENT (mA)
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX6765 toc07
OUTPUT VOLTAGE vs. LOAD CURRENT
VOUT = 5V 3.34 3.32 OUTPUT VOLTAGE (V) 3.30 3.28 3.26 3.24 3.22 3.20 VOUT = 3.3V
MAX6765 toc08
5.20 5.15 OUTPUT VOLTAGE (V) 5.10 5.05 5.00 4.95 4.90 4.85 4.80 0
10 20 30 40 50 60 70 80 90 100 LOAD CURRENT (mA)
0
10 20 30 40 50 60 70 80 90 100 LOAD CURRENT (mA)
MAX6765 toc03
44
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Typical Operating Characteristics (continued)
(VIN = 14V, COUT = 10F, CIN = 0.1F, TA = +25C, unless otherwise noted.)
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX6765 toc09
RESET TIMEOUT PERIOD vs. CAPACITOR VALUE
MAX6765 toc10
NORMALIZED RESET TIMEOUT PERIOD vs. TEMPERATURE
NORMALIZED RESET TIMEOUT PERIOD 1.08 1.06 1.04 1.02 1.00 0.98 0.96 0.94 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C)
MAX6765 toc11
1.85 1.84 1.83 OUTPUT VOLTAGE (V) 1.82 1.81 1.80 1.79 1.78 1.77 1.76 1.75 0
VOUT = 1.8V
160 140 RESET TIMEOUT PERIOD (ms) 120 100 80 60 40 20 0
1.10
10 20 30 40 50 60 70 80 90 100 LOAD CURRENT (mA)
0
25
50
75
100
125
CAPACITOR VALUE (nF)
NORMALIZED WATCHDOG TIMEOUT vs. TEMPERATURE
MAX6765 toc12
RESET OUTPUT vs. SINK CURRENT
MAX6765 toc13
RESET OUTPUT vs. SOURCE CURRENT
5.0 4.5 RESET OUTPUT (V) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 VOUT = 5V
MAX6765 toc14
1.06 NORMALIZED WATCHDOG TIMEOUT 1.04 1.02
4.0 VOUT = 5V 3.5 3.0 RESET OUTPUT (V) 2.5 2.0 1.5 1.0 0.5 0
5.5
1.00 0.98 0.96 0.94 0.92 0.90 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C)
0
5
10
15
20
25
30
35
40
0
2
4
6
8
10
12
14
16
SINK CURRENT (mA)
SOURCE CURRENT (mA)
SUPPLY CURRENT vs. WATCHDOG INPUT FREQUENCY
VOUT = 5V 41 SUPPLY CURRENT (A) 40 39 38 37 36 35 34 0.001 0.01 0.1 1 10 100
MAX6765 toc15
OUT AND HOLD vs. ENABLE
MAX6765 toc16
42
ENABLE 5V/div
GATE 5V/div HOLD 5V/div OUT 5V/div
20ms/div (SEE TEST CIRCUIT FOR ENABLE AND HOLD)
WATCHDOG INPUT FREQUENCY (kHz)
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Typical Operating Characteristics (continued)
(VIN = 14V, COUT = 10F, CIN = 0.1F, TA = +25C, unless otherwise noted.)
POWER-SUPPLY REJECTION RATIO vs. FREQUENCY
MAX6765 toc17
NORMALIZED OUT VOLTAGE vs. INPUT VOLTAGE
VOUT = 3.3V 1.0015 NORMALIZED OUT VOLTAGE 1.0010 1.0005 1.0000 0.9995 0.9990 0.9985 0.9980
MAX6765 toc18
40 POWER-SUPPLY REJECTION RATIO (dB) 20 0 -20 -40 -60 -80 -100 -120 -140 -160 -180 0.1 1 10 100 1k 10k 100k
1.0020
1M
4
12
20
28
36
44
52
60
68
FREQUENCY (Hz)
INPUT VOLTAGE (V)
LOAD-TRANSIENT RESPONSE
MAX6765 toc19
LINE-TRANSIENT RESPONSE
MAX6765 toc20
VOUT = 5V
VOUT = 5V OUT (AC-COUPLED) 1V/div
OUT (AC-COUPLED) 200mV/div
IOUT 100mA/div
VIN 10V/div
100ms/div
400s/div
LINE-TRANSIENT RESPONSE
MAX6765 toc21
SERIES RESISTANCE vs. LOAD CURRENT
10 SERIES RESISTANCE () OUT (AC-COUPLED) 1V/div 9 8 7 6 5 4 3 2 1 0 0 20 40 60 80 100 STABLE OPERATING REGION
MAX6765 toc22
11
VOUT = 5V
VIN 20V/div 400s/div
LOAD CURRENT (mA)
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Enable and Hold Test Circuit
VIN
IN ENABLE ENABLE
OUT
OUT
MAX6767 MAX6768
GND
HOLD
HOLD
N TEST CIRCUIT FOR OUT AND HOLD VS. ENABLE
GATE
Pin Description
PIN MAX6765/ MAX6767/ MAX6766 MAX6768 1 2 3 1 2 3 MAX6769/ MAX6770 1 2 3 MAX6771/ MAX6773/ MAX6772 MAX6774 1 2 -- 1 2 3 NAME FUNCTION Regulator Input. Bypass IN to GND with a capacitor with a minimum value of 0.1F. Ground Active-High Enable Input. Drive ENABLE high to turn on the regulator. ENABLE is internally connected to GND through a 0.6A current sink. Active-Low, Open-Drain/Push-Pull Reset Output. For the MAX6769/MAX6770, RESET asserts when RESETIN is below the internal VTH and deasserts when RESETIN is above the internal VTH threshold. For all other versions, RESET remains low while OUT is below the reset threshold. For all versions, RESET remains low for the duration of the reset timeout period after the reset conditions end.
IN GND ENABLE
4
5
5
5
5
RESET
5
7
7
7
7
Reset Timeout Adjust Input. Connect TIMEOUT to OUT for the internally fixed timeout period. For an adjustable TIMEOUT timeout, connect a capacitor from TIMEOUT to GND. See the Selecting Timeout Capacitor section. Regulator Output. The MAX6765/MAX6766 provide a fixed output (+1.8V, +2.5V, +3.3V, or +5V). The MAX6767-MAX6774 provide a fixed output voltage of +1.8V, +2.5V, +3.3V, or 5V, or adjust the output from +1.8V to +11V. Bypass to GND with a 10F capacitor (min).
6
8
8
8
8
OUT
8
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Automotive Micropower Linear Regulators with Supervisor
Pin Description (continued)
PIN MAX6765/ MAX6767/ MAX6766 MAX6768 MAX6769/ MAX6770 MAX6771/ MAX6773/ MAX6772 MAX6774 NAME FUNCTION Active-Low Regulator Hold Input. When HOLD is forced low, OUT remains on even if ENABLE is pulled low. To shut down the regulator, release HOLD after ENABLE is pulled low. Connect HOLD to OUT or leave unconnected if unused. HOLD is internally connected to OUT through a 1.8A current source. Feedback Input for Setting the Output Voltage. Connect SET to GND to select the preset output voltage. Connect to an external resistive divider for adjustable output operation. Adjustable Reset Threshold Input. Connect to a resistive divider to set the desired threshold.
MAX6765-MAX6774
--
4
--
--
--
HOLD
--
6
6
6
6
SET
--
--
4
--
--
RESETIN
--
--
--
3
--
Active-High Enable Input 1. Drive ENABLE1 high to turn ENABLE1 on the regulator. ENABLE1 is internally connected to ground through a 0.6A current sink. Active-High Enable Input 2. Drive ENABLE2 high to turn ENABLE2 on the regulator. ENABLE2 is internally connected to ground through a 0.6A current sink. Watchdog Timer Input. If WDI remains high or low for longer than the watchdog timeout period, the internal watchdog timer expires and the reset output asserts for the reset timeout period. The internal watchdog timer clears whenever a reset is asserted or WDI sees a rising or falling edge. The watchdog timer cannot be disabled. Do not leave WDI unconnected. Exposed Paddle. EP is internally connected to GND. Connect EP to the ground plane to provide a low thermal-resistance path from the IC junction to the PCB. Do not use as the electrical connection to GND.
--
--
--
4
--
--
--
--
--
4
WDI
EP
EP
EP
EP
EP
--
Detailed Description
The MAX6765-MAX6774 low-quiescent-current, highvoltage linear regulators operate from a 4V to 72V input voltage and deliver more than 100mA of load current. The MAX6765-MAX6774 include an integrated P reset circuit that monitors the regulator output voltage and asserts a reset output when OUT falls below a threshold limit, and includes an internally fixed or adjustable reset timeout using a capacitor from TIMEOUT to ground. All devices are available in a preset output-voltage option of
+1.8V, +2.5V, +3.3V, and +5V. The output voltage of the MAX6767-MAX6774 is adjustable from +1.8V to +11V using a resistive divider at SET. The MAX6773/MAX6774 include a watchdog timer (WDI) with a 1.6s (typ) watchdog timeout period. The MAX6769/MAX6770 feature an adjustable reset threshold using a resistive divider between the monitored voltage, RESETIN, and GND; see the Functional Diagrams. The MAX6771/MAX6772 provide dual enable inputs (ENABLE1 and ENABLE2) to turn on and off the regulator either through an ignition switch or a bus transceiver.
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Functional Diagrams
THERMAL PROTECTION IN OVERCURRENT PROTECTION
MAX6765/MAX6766 OUT
ENABLE
CONTROL LOGIC
1.147V 1.233V OR 1.085V
RESET TIMEOUT
RESET
TIMEOUT GND
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Functional Diagrams (continued)
MAX6765-MAX6774
THERMAL PROTECTION IN OVERCURRENT PROTECTION
MAX6767/MAX6768 OUT
ENABLE HOLD
CONTROL LOGIC
SET 116mV 1.147V 1.233V OR 1.085V RESET TIMEOUT RESET
TIMEOUT GND
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Functional Diagrams (continued)
THERMAL PROTECTION IN OVERCURRENT PROTECTION
MAX6769/MAX6770 OUT
ENABLE
CONTROL LOGIC
SET 116mV 1.147V 1.233V OR 1.085V RESET TIMEOUT RESET
RESETIN GND
TIMEOUT
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Automotive Micropower Linear Regulators with Supervisor
Functional Diagrams (continued)
MAX6765-MAX6774
THERMAL PROTECTION IN OVERCURRENT PROTECTION
MAX6771/MAX6772 OUT
ENABLE1 ENABLE2
CONTROL LOGIC
SET 116mV 1.147V 1.233V OR 1.085V RESET TIMEOUT RESET
TIMEOUT GND
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Functional Diagrams (continued)
THERMAL PROTECTION IN OVERCURRENT PROTECTION
MAX6773/MAX6774 OUT
ENABLE
CONTROL LOGIC
SET 116mV 1.147V 1.233V OR 1.085V RESET TIMEOUT RESET
TIMEOUT GND
WDI
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Automotive Micropower Linear Regulators with Supervisor
Regulator
The regulator accepts an input voltage from +4V to +72V. All of the devices feature fixed output-voltage options of +1.8V, +2.5V, +3.3V, and +5V. The MAX6767-MAX6774 feature an adjustable output voltage set with an external resistive-divider network connected between OUT, SET, and GND. See Figure 1.
VIN
MAX6765-MAX6774
IN OUT R1 MAX6767-MAX6774 SET
Enable and Hold Inputs (MAX6767/MAX6768)
The MAX6767/MAX6768 support two logic inputs, ENABLE (active-high) and HOLD (active-low), making these devices "automotive friendly." For example, when the ignition key signal drives ENABLE high, the regulator turns on and remains on even if ENABLE goes low, as long as HOLD is forced low and kept low before ENABLE goes low. In this state, releasing HOLD turns the regulator output (OUT) off. This feature makes it possible to implement a self-holding circuit without external components. Forcing ENABLE low with HOLD high (or unconnected) places the MAX6767/MAX6768 into shutdown mode, drawing 3.3A (typ) of supply current. Table 3 shows the state of the regulator output with respect to the voltage level at ENABLE and HOLD. Connect HOLD to OUT or leave it unconnected to allow the ENABLE input to act as a standard enable/shutdown switch for the regulator output (OUT).
GND
R2
Figure 1. Setting the Output Voltage Using a Resistive Divider
Table 1. Preset Timeout Period
PART NUMBER SUFFIX (_) D0 D1 D2 D3 D4 TIMEOUT PERIOD 75s 3.125ms 12.5ms 50ms 200ms
Reset Output
The reset output is typically connected to the reset input of a P. A P's reset input starts or restarts the P in a known state. The MAX6765-MAX6774 supervisory circuits provide the reset logic to prevent code-execution errors during power-up, power-down, and brownout conditions (see the Typical Application Circuit). RESET changes from high to low whenever the monitored voltage drops below the reset threshold voltages. Once the monitored voltage exceeds its respective reset threshold voltage(s), RESET remains low for the reset timeout period, then goes high. See Table 1.
Table 2. Preset Output Voltage and Reset Threshold
PART NUMBER SUFFIX (_) L M T S Z Y W V OUTPUT VOLTAGE (V) 5 5 3.3 3.3 2.5 2.5 1.8 1.8 RESET THREHOLD (V) 4.625 4.375 3.053 2.888 2.313 2.188 1.665 1.575
RESETIN Threshold (MAX6769/MAX6770)
The MAX6769/MAX6770 monitor the voltage on RESETIN using an adjustable reset threshold (VRESETIN) set with an external resistive voltage-divider and the internal reset threshold VTH. See Table 2.
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Table 3. ENABLE/HOLD Truth Table/State Table
OPERATING STATE Initial State Turn-On State Hold Setup State Hold State ENABLE Low High High Low HOLD Don't care Don't care Low Low High (floats high) REGULATOR OUTPUT Off On On On COMMENT ENABLE is pulled to GND through an internal pulldown. HOLD is floating (pulled up to OUT). Regulator output is disabled. ENABLE is externally driven high turning the regulator output on. HOLD is pulled up by OUT. HOLD is externally pulled low while ENABLE remains high (latches HOLD state). ENABLE is driven low (or allowed to float low by an internal pulldown). HOLD remains externally pulled low keeping the regulator output on. HOLD is driven high (or allowed to float high by an internal pullup) while ENABLE is low. Regulator output is shut off and ENABLE/ HOLD logic returns to the initial state.
Off-State
Low
Off
Watchdog Timer (MAX6773/MAX6774)
The MAX6773/MAX6774 include a watchdog timer that asserts RESET if the watchdog input (WDI) does not toggle within the watchdog timeout period tWD (1.6s, typ). RESET remains low for the reset timeout period, tRP. If the watchdog is not updated for lengthy periods of time, the reset output appears as a pulse train, asserted for the reset timeout period and deasserted for the watchdog timeout period, until WDI is toggled again. When RESET asserts, it stays low for the entire reset timeout period ignoring any WDI transitions. To prevent the watchdog from asserting RESET, toggle WDI with a valid rising or falling edge prior to tWD (min) = 1.12s. The watchdog counter clears when WDI toggles prior to tWD or when RESET asserts. The watchdog resumes counting after RESET deasserts. The watchdog timer cannot be disabled.
voltage mode. In preset voltage mode, internal trimmed feedback resistors set the internal linear regulator to +1.8V, +2.5V, +3.3V, or +5V (see Table 2). Select preset-voltage mode by connecting SET to ground. In adjustable mode, select an output voltage between +1.8V and +11V using two external resistors connected as a voltage-divider to SET (see Figure 1). Set the output voltage using the following equation: VOUT = VSET (1 + R1 / R2) where VSET = 1.233V and the recommended value for R2 is 50k (maximum 100k).
RESETIN Threshold Selection
The MAX6769/MAX6770 feature an adjustable reset threshold to monitor the voltage on RESETIN using a resistive divider between the monitored voltage, RESETIN and GND. See Figure 2. Use the following formula to set the desired reset threshold: VMON = VTH (1 + R3 / R4) where V TH is 1.085V for the M/S/Y/V versions and 1.147V for L/T/Z/W versions.
VMON VIN IN R3 MAX6769 MAX6770 RESETIN R4 GND RESET
Thermal Protection
When the junction temperature exceeds TJ = +160C (typ), an internal thermal sensor signals the shutdown logic that turns off the pass transistor and allows the IC to cool. The thermal sensor turns the pass transistor on again after the IC's junction temperature cools by 20C (typ), resulting in a cycled output during continuous thermal-overload conditions. Thermal protection protects the MAX6765-MAX6774 in the event of a fault condition. Never exceed the absolute maximum junction temperature rating of TJ = +150C. See Figures 3 and 4 for the safe operating area.
Applications Information
Output Voltage Selection
The MAX6767-MAX6774 feature dual-mode operation: these devices operate in either a preset or adjustable
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Figure 2. RESETIN Threshold Selection
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Automotive Micropower Linear Regulators with Supervisor
Available Output-Current Calculation
The MAX6765-MAX6774 provide up to 100mA of load current. Package power dissipation limits the amount of output current available for a given input/output voltage and ambient temperature. Figures 3 and 4 depict the maximum power dissipation curve for the MAX6765/ MAX6766 and MAX6767-MAX6774, respectively. The graph assumes that the exposed metal pad of the device package is soldered to a solid 1in2 section of 2oz. PCB copper (JESD51-3 AND JESD51-5). Use Figure 4 to determine the allowable package dissipation for a given ambient temperature. Alternately, use the following formula to calculate the allowable package dissipation: PDMAX = Max. Power Dissip = 1.951W, for TA +70C PDMAX = Max. Power Dissip = [1.9W - 0.0244W x (TA - 70C)], for +70C < TA +125C where 0.0244W is the MAX6767-MAX6774 package thermal derating in W/C and TA is the ambient temperature in C, under the same conditions used for Figure 4. After determining the allowable package dissipation, calculate the maximum output current using the following formula: PD < PDMAX where PD = [(VIN - VOUT) x IOUT] Also, IOUT should be 100mA in any case.
Selecting Timeout Capacitor
The reset timeout period is adjustable to accommodate a variety of P applications. Adjust the reset timeout period by connecting a capacitor between TIMEOUT and GND. tRP = CTIMEOUT x 1.22 x 106 where tRP is in seconds and CTIMEOUT is in Farads. Connect TIMEOUT to OUT to select the internally fixed timeout period. C TIMEOUT must be a low-leakage (< 10nA) type capacitor. Ceramic capacitors are recommended; do not use capacitor values lower than 100pF to avoid the influence of parasitic capacitances.
MAX6765-MAX6774
Capacitor Selection and Regulator Stability
For stable operation over the full temperature range and with load currents up to 100mA, use a 10F (min) output capacitor with an ESR < 0.5. To reduce noise and improve load-transient response, stability, and powersupply rejection, use larger output-capacitor values. Some ceramic dielectrics exhibit large capacitance and ESR variation with temperature. For dielectric capacitors such as Z5U and Y5V, use more capacitance to ensure stability at low temperatures. With X7R or X5R dielectrics, 10F should be sufficient at all operating temperatures. For higher-ESR tantalum capacitors, use larger capacitor values to maintain stability. To improve power-supply rejection and transient response, use a larger capacitor than the minimum 0.1F capacitor between IN and GND.
MAX6765 fig03
2.2 2.0 1.8 1.6 PD (W) 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0
1.904W DERATE 23.8mW/C ABOVE +70C
2.2 2.0 1.8 1.6 PD (W) 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0
1.951W SAFE OPERATING AREA DERATE 24.4mW/C ABOVE +70C
SAFE OPERATING AREA
20
40
60
80
100 120 140 160
0
20
40
60
80
100 120 140 160
TEMPERATURE (C)
TEMPERATURE (C)
Figure 3. Maximum Power Dissipation vs. Temperature (MAX6765/MAX6766)
Figure 4. Maximum Power Dissipation vs. Temperature (MAX6767-MAX6774)
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MAX6765 fig04
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Ensuring a Valid RESET Output Down to VIN = 0V (MAX6766/MAX6768/MAX6770/ MAX6772/MAX6774)
When VIN falls below 1V, RESET current-sinking capabilities decline drastically. High-impedance CMOSlogic inputs connected to RESET can drift to undetermined voltages. This presents no problems in most applications, since most Ps and other circuitry do not operate with supply voltages below 1V. In those applications where RESET must be valid down to 0V, adding a pulldown resistor between RESET and ground sinks any stray leakage currents, holding RESET low (Figure 5). The value of the pulldown resistor is not critical; 100k is large enough not to load RESET and small enough to pull RESET to ground. Open-drain RESET versions are not recommended for applications requiring valid logic for VIN down to 0V.
VIN
IN MAX6766 MAX6768 MAX6770 MAX6772 MAX6774 RESET GND
Figure 5. Ensuring RESET Valid to VIN = 0V
Table 4. Standard Version Part Numbers
PART MAX6765TTLD2+T MAX6765TTSD2+T MAX6766TTLD2+T MAX6766TTSD2+T MAX6767TALD2+T MAX6767TASD2+T MAX6768TALD2+T MAX6768TASD2+T MAX6769TALD2+T MAX6769TASD2+T MAX6770TALD2+T MAX6770TASD2+T MAX6771TALD2+T MAX6771TASD2+T MAX6772TALD2+T MAX6772TASD2+T MAX6773TALD2+T MAX6773TASD2+T MAX6774TALD2+T MAX6774TASD2+T OUTPUT VOLTAGE (V) 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 5 3.3 RESET TIMEOUT PERIOD (ms) 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 RESET THRESHOLD (V) 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 4.625 2.888 TOP MARK +AQB +AQL +ARO +ARZ +AVI +AVS +AVZ +AXE +AYH +AYQ +AZS +BAC +BEG +BEQ +APY +BGC +BBG +AQE +BCS +BDC
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Automotive Micropower Linear Regulators with Supervisor
Selector Guide
PART MAX6765 MAX6766 MAX6767 MAX6768 MAX6769 MAX6770 MAX6771 MAX6772 MAX6773 MAX6774 RESET OUTPUT Open drain Push-pull Open drain Push-pull Open drain Push-pull Open drain Push-pull Open drain Push-pull WATCHDOG INPUT -- -- -- -- -- -- -- -- OUTPUT VOLTAGE Fixed Fixed Fixed/Adj Fixed/Adj Fixed/Adj Fixed/Adj Fixed/Adj Fixed/Adj Fixed/Adj Fixed/Adj RESETIN THRESHOLD -- -- -- -- -- -- -- -- ENABLE INPUTS Single Single Single Single Single Single Dual Dual Single Single HOLD INPUT -- -- -- -- -- -- -- --
MAX6765-MAX6774
Typical Application Circuit
OUT MAX6766 TIMEOUT 12V BATTERY GND C ENABLE RESET RESET
IN
VCC TXD XCVR RXD LIN
I/O
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Pin Configurations (continued)
TIMEOUT TIMEOUT
TOP VIEW
OUT
TOP VIEW
RESET OUT SET
8
7
6
5
8
7
6
MAX6767 MAX6768
+ 1 IN 2 GND 3 ENABLE 4 HOLD + 1 IN
MAX6769 MAX6770
2 GND
3 ENABLE SET 6 3 ENABLE
TDFN
TDFN
TIMEOUT
TIMEOUT
TOP VIEW
OUT
TOP VIEW
RESET OUT SET
8
7
6
5
8
7
MAX6771 MAX6772
+ 1 IN 2 GND 3 ENABLE1 4 ENABLE2 + 1 IN
MAX6773 MAX6774
2 GND
TDFN
TDFN
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WDI
RESET 5 4
RESETIN
RESET 5 4
SET
Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Ordering Information (continued)
PART MAX6767TA_D_+ MAX6768TA_D_+ MAX6769TA_D_+ MAX6770TA_D_+ MAX6771TA_D_+ MAX6772TA_D_+ MAX6773TA_D_+ MAX6774TA_D_+ TEMP RANGE PINPACKAGE PKG CODE T833-2 T833-2 T833-2 T833-2 T833-2 T833-2 T833-2 T833-2
Chip Information
PROCESS: BiCMOS
-40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP** -40C to +125C 8 TDFN-EP**
The first "_" is a placeholder for the voltage output and reset threshold. The 2nd "_" designates the fixed reset-timeout option. See Tables 1 and 2 for details. For example, the MAX6765TTLD4 has a 5V output, a reset threshold of 4.65V, and a 200ms typical reset timeout. +Denotes lead-free package. *Future product--contact factory for availability. **EP = Exposed paddle. For tape-and-reel orders add a "T" after the "+" symbol to complete the part number. Tape-and-reel orders are available in 2.5k increments. Nonstandard versions require a 10k minimum order quantity.
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Automotive Micropower Linear Regulators with Supervisor MAX6765-MAX6774
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
6, 8, &10L, DFN THIN.EPS
PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm
21-0137
H
1 2
22
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Automotive Micropower Linear Regulators with Supervisor
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)
MAX6765-MAX6774
COMMON DIMENSIONS SYMBOL A D E A1 L k A2 MIN. 0.70 2.90 2.90 0.00 0.20 MAX. 0.80 3.10 3.10 0.05 0.40
PACKAGE VARIATIONS PKG. CODE T633-1 T633-2 T833-1 T833-2 T833-3 T1033-1 T1033-2 T1433-1 T1433-2 N 6 6 8 8 8 10 10 14 14 D2 1.500.10 1.500.10 1.500.10 1.500.10 1.500.10 1.500.10 1.500.10 1.700.10 1.700.10 E2 2.300.10 2.300.10 2.300.10 2.300.10 2.300.10 2.300.10 2.300.10 2.300.10 2.300.10 e 0.95 BSC 0.95 BSC 0.65 BSC 0.65 BSC 0.65 BSC 0.50 BSC 0.50 BSC 0.40 BSC 0.40 BSC JEDEC SPEC MO229 / WEEA MO229 / WEEA MO229 / WEEC MO229 / WEEC MO229 / WEEC MO229 / WEED-3 MO229 / WEED-3 ------b 0.400.05 0.400.05 0.300.05 0.300.05 0.300.05 0.250.05 0.250.05 0.200.05 0.200.05 [(N/2)-1] x e 1.90 REF 1.90 REF 1.95 REF 1.95 REF 1.95 REF 2.00 REF 2.00 REF 2.40 REF 2.40 REF
0.25 MIN. 0.20 REF.
PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm
-DRAWING NOT TO SCALE-
21-0137
H
2 2
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 23 (c) 2006 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.

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