View MAX15054AUT_4584881.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-4747; Rev 0; 9/09
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications
General Description
The MAX15054 is a high-side, n-channel MOSFET driver for high-voltage applications capable of switching at high frequencies. This device is controlled by a CMOS logiclevel signal referenced to ground and features a very short (12ns, typ) propagation delay from input to output. The high-voltage operation and high source/sink-current capability make the MAX15054 ideal for HB LED drivers and DC-DC converters. The MAX15054 is well suited to complement other Maxim LED driver products such as the MAX16814, MAX16838, MAX16833, MAX16834, and MAX16826. The MAX15054 adds a high-side driver to those products that include only a low-side driver; it then allows for buck-boost configurations for multistring drivers similar to the MAX16814, MAX16838, and MAX16826, and for buck-boost conversion with output referenced to ground for single-string drivers such as the MAX16834 and MAX16833. The MAX15054 is available in the industry-standard 6-pin SOT23 package and operates over the -40NC to +125NC automotive temperature range. to 60V
Features
S Input Voltage on High-Side n-Channel MOSFET Up S Up to 13.5V Logic Input Independent of Supply
MAX15054
Voltage
S 2A Peak Source and Sink Current S 12ns Propagation Delay S Rise and Fall Times of 6ns while Driving 1000pF
Capacitance
S Low Input Capacitance S Low-Side and High-Side Undervoltage Protection S Allows Buck-Boost Topology Referred to Ground
for LED Drivers and DC-DC Converters
S Allows Buck-Boost Topology for Multistring LED
Drivers
S 6-Pin SOT23 Package
Ordering Information
PART TEMP RANGE PINPACKAGE 6 SOT23 TOP MARK ACOM
Applications
HB LED Drivers for Single and Multiple Strings LED Backlight Drivers High-Side Driver for DC-DC Converters (Buck, Buck-Boost, Half-Bridge, Full-Bridge)
MAX15054AUT+ -40NC to +125NC
+Denotes a lead(Pb)-free/RoHS-compliant package.
Pin Configuration appears at end of data sheet.
Typical Operating Circuits
VIN D1
VDD C1
BST CBST
MAX15054
HDRV LX
Q1
GND
HI D2
L1
D3 R8 C5
R1
C2
IN
CFB
GATE NDRV DRAIN R9
R2
EN VCC C3 R3 VDRV
OV OUT1 OUT2
C4
MAX16838
ISET FLT CS RT
R7
DIM COMP R4 SGND C4 PGND LEDGND
R6
R5
Typical Operating Circuits continued at end of data sheet. _______________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications MAX15054
ABSOLUTE MAXIMUM RATINGS
VDD to GND ............................................................. -0.3V to +6V Thermal Resistance (Note 1) LX to GND ................................................................ -2V to +65V Junction-to-Ambient Thermal Resistance (BJA) .........115NC/W HDRV to LX................................................-0.3V to (VDD + 0.3V) Junction-to-Case Thermal Resistance (BJC) ................80NC/W BST to LX ................................................................. -0.3V to +6V Operating Temperature Range ........................ -40NC to +125NC HI to GND .............................................................. -0.3V to +15V Maximum Junction Temperature .....................................+150NC dV/dt at LX ........................................................................ 50V/ns Storage Temperature Range ............................ -65NC to +150NC Peak Current into HDRV (< 100ns) ...................................... Q2A Lead Temperature (soldering, 10s).................................+300NC Continuous Current into HDRV ..................................... Q100mA Continuous Power Dissipation (TA = +70NC) 6-Pin SOT23 (derate 8.7mW/NC above +70NC) .........695.7mW Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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
(VDD = VBST = 5V, VLX = VGND = 0V, TA = TJ = -40C to +125C, unless otherwise noted. Typical values are at TA = TJ = +25C, unless otherwise noted.) (Note 2) PARAMETER Operating Supply Voltage VDD Quiescent Supply Current BST Quiescent Supply Current BST Operating Supply Current VDD Undervoltage Lockout Threshold VDD Undervoltage Lockout Threshold Hysteresis BST-to-LX Undervoltage Lockout Threshold BST-to-LX Undervoltage Lockout Threshold Hysteresis LOGIC INPUT (HI) HI Logic-High Threshold HI Logic-Low Threshold HI Logic-Input Hysteresis HI Input Current HI Input Resistance DRIVER LX Withstand Voltage BST Withstand Voltage LX Pulldown Current Driver Output Resistance (Sourcing) Driver Output Resistance (Sinking) RON_HP RON_HN VLX_MAX VBST_MAX VLX = 2.5V VBST - VLX = 4.5V, 100mA sourcing VBST - VLX = 4.5V, 100mA sinking TA = +25NC TA = +125NC TA = +25NC TA = +125NC 500 740 1 1.25 0.75 1 60 65 1100 1.5 2 1 1.5 V V FA I I IIN RIN HI = GND -2 300 VIH VIL 0.9 +2 3.9 1.8 V V V FA kI VBST_
UVLO
SYMBOL VDD IDD IBST IBSTO VDD_UVLO No switching No switching
CONDITIONS
MIN 4.6
TYP 40 65 0.3
MAX 5.5 75 125 1.3 4.56
UNITS V FA FA mA V V
fSW = 500kHz, no load VDD rising 3.92
4.22 0.2
BST rising
3.54
3.82 0.2
4.1
V V
2
______________________________________________________________________________________
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications
ELECTRICAL CHARACTERISTICS (continued)
(VDD = VBST = 5V, VLX = VGND = 0V, TA = TJ = -40C to +125C, unless otherwise noted. Typical values are at TA = TJ = +25C, unless otherwise noted.) (Note 2) PARAMETER Peak Output Current (Sourcing) Peak Output Current (Sinking) SWITCHING CHARACTERISTICS No-load capacitor Rise Time tR CL = 1000pF CL = 5000pF No-load capacitor Fall Time Turn-On Propagation Delay Turn-Off Propagation Delay tF tD_ON tD_OFF CL = 1000pF CL = 5000pF Figure 1, CL = 1000pF (Note 3) Figure 1, CL = 1000pF (Note 3) 1.5 6 18 1.5 6 16 11 11 25 25 ns ns ns ns SYMBOL IPK_HP IPK_HN VHDRV = 0V VHDRV = 5V CONDITIONS MIN TYP 2.5 2.5 MAX UNITS A A
MAX15054
Note 2: All devices are 100% production tested at TA = +25NC. Limits over the operating temperature range are guaranteed by design. Note 3: Guaranteed by design.
VIH VIL VHI tD_ON 90% tD_OFF
VHDRV
10% tR tF
Figure 1. Turn-On/Turn-Off Propagation Delay
_______________________________________________________________________________________
3
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications MAX15054
Typical Operating Characteristics
(VDD = VBST = 5V, VLX = VGND = 0V, TA = +25C, unless otherwise noted.)
VDD UNDERVOLTAGE LOCKOUT THRESHOLD vs. TEMPERATURE
MAX15054 toc01
BST-LX UNDERVOLTAGE LOCKOUT THRESHOLD vs. TEMPERATURE
MAX15054 toc02
POWER-UP AND POWER-DOWN SEQUENCE
MAX15054 toc03
4.250 4.225 4.200 UVLO THRESHOLD (V) 4.175 4.150 4.125 4.100 4.075 4.050 4.025 4.000 3.975 VDD FALLING VDD RISING
3.875 3.850 3.825 UVLO THRESHOLD (V) 3.800 3.775 3.750 3.725 3.700 3.675 3.650 3.625 3.600 BST-LX FALLING BST-LX RISING
fSW = 5kHz AT HI
VDD 1V/div HDRV 1V/div 0V
-40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (NC)
-40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C)
400s/div
POWER-UP AND POWER-DOWN SEQUENCE
MAX15054 toc04
VDD, BST-LX QUIESCENT SUPPLY CURRENT vs. SUPPLY VOLTAGE
70 65 60 55 50 45 40 35 30 25 20 15 10 5 0
MAX15054 toc05
fSW = 5kHz AT HI
VDD 1V/div HDRV 1V/div
QUIESCENT CURRENT (A)
IBST TA = +125NC TA = +85NC TA = +25NC IDD
0V 40s/div
TA = -40NC 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V)
BST OPERATING SUPPLY CURRENT vs. SWITCHING FREQUENCY
1750 1500 IBSTO (A) 1250 1000 750 500 250 0 0.1 1.0 10 100 1000 SWITCHING FREQUENCY (kHz) 10,000 NO LOAD ON HDRV
MAX15054 toc06
HI INPUT THRESHOLDS vs. TEMPERATURE
3.75 INPUT THRESHOLD (V) 3.50 3.25 3.00 2.75 2.50 2.25 2.00 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (NC) FALLING RISING
MAX15054 toc07
2000
4.00
4
______________________________________________________________________________________
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications
Typical Operating Characteristics (continued)
(VDD = VBST = 5V, VLX = VGND = 0V, TA = +25C, unless otherwise noted.)
HDRV OUTPUT HIGH/LOW vs. TEMPERATURE
HI 2V/div
MAX15054
2MHz OPERATION
MAX15054 toc08
120 OUTPUT HIGH/LOW (V) 100 80 60 40 20 0
VBST - VHDRV SOURCING 100mA
0V HDRV 2V/div
VHDRV - VLX SINKING 100mA
0V
NO LOAD ON HDRV
200ns/div
OUTPUT HIGH = VBST - VHDRV OUTPUT LOW = VHDRV - VLX -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (NC)
4% DUTY CYCLE AT 2MHz
MAX15054 toc10
96% DUTY CYCLE AT 2MHz
MAX15054 toc11
TURN-ON/TURN-OFF PROPAGATION DELAY vs. TEMPERATURE
2V/div PROPAGATION DELAY (ns) 12.5 12.0 11.5 11.0 10.5 10.0 9.5 9.0 8.5 8.0
MAX15054 toc12
13.0
HI 2V/div 0V
MAX15054 toc09
140
tD_OFF
HDRV 2V/div 0V 10ns/div
10ns/div
2V/div
tD_ON
-40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C)
RISE TIME AND FALL TIME
MAX15054 toc13
TURN-ON AND TURN-OFF PROPAGATION DELAY
MAX15054 toc14
HI
2V/div
HDRV
0V
HI HDRV
1V/div
2V/div
4.7nF CAPACITOR CONNECTED FROM HDRV TO GND, LX = GND
20ns/div
HDRV
0V
0V
HI
1nF CAPACITOR CONNECTED FROM HDRV TO GND, LX = GND
40ns/div
_______________________________________________________________________________________
5
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications MAX15054
Pin Description
PIN 1 2 3 4 5 6 NAME HI GND VDD BST HDRV LX FUNCTION 5V CMOS Logic Input. HI is referenced to GND and is capable of withstanding voltages up to 13.5V for any VDD voltage. Ground Input Supply Voltage. Valid supply voltage ranges from 4.6V to 5.5V. Bypass VDD to GND with a 0.1FF ceramic capacitor as close as possible to the device. Boost Flying Capacitor Connection. Connect a minimum of a 0.1FF ceramic capacitor between BST and LX for the high-side MOSFET driver supply. Connect a bootstrap Schottky diode between VDD and BST. High-Side Gate-Driver Output. Driver output to drive the high-side external MOSFET gate. Source Connection for High-Side MOSFET. LX also serves as a return terminal for the high-side driver.
Functional Diagram
BST
D1 EXTERNAL
HIGH-SIDE UVLO
HDRV
MAX15054
VDD LOW-SIDE UVLO HI GND LEVEL SHIFT UP LEVEL SHIFT DOWN
LX
Detailed Description
The MAX15054 n-channel MOSFET driver controls an external high-side MOSFET in high-voltage, high-current applications. This driver operates with a supply voltage of 4.6V to 5.5V, and consumes only 300FA of supply current during typical switching operations (fSW = 500kHz) and no-load conditions. The MAX15054 provides 2.5A (typ) sink/source peak current and is capable of operating with large capacitive loads and with switching frequencies up to 2MHz. The device is used to drive the high-side MOSFET without requiring an isolation device such as an optocoupler or a drive transformer.
6
The high-side driver is controlled by a CMOS logic referenced to ground and is powered by a bootstrap circuit formed by an external diode and capacitor. Undervoltage lockout (UVLO) protection is provided for both the high- and low-side driver supplies (BST and VDD) and includes a UVLO hysteresis of 0.2V (typ). The MAX15054's fast switching times and very short propagation delays (11ns, typ) are ideal for highfrequency applications. Internal logic circuitry prevents shoot-through during output state changes and minimizes package power dissipation.
______________________________________________________________________________________
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications
The MAX15054 drives an external high-side MOSFET. Both the high- and low-side supplies feature separate UVLO protection that monitors each driver's input supply voltage (BST-LX and VDD). The low-side supply UVLO threshold (VDD_UVLO) is referenced to GND and pulls the driver output low when VDD falls below 4V (typ) irrespective of the high-side UVLO condition. The high-side driver UVLO threshold (VBST_UVLO) is referenced to LX, and pulls HDRV low when VBST falls below 3.6V (typ) with respect to LX. After the MAX15054 is first energized (VDD > VDD_UVLO), the bootstrap capacitor (CBST) between BST and LX is not charged, and HDRV does not switch since the BST-to-LX voltage is below VBST_UVLO. An internal charging circuit charges the BST-LX supply through an external Schottky diode and within a short time CBST charges through VDD and causes VBST to exceed VBST_UVLO. HDRV then starts switching and follows HI. The hysteresis is 0.2V (typ) for both UVLO thresholds. The MAX15054 driver contains low on-resistance p-channel and n-channel devices in a totem pole configuration for the driver output stage. This allows for rapid turn-on and turn-off of high gate-charge (Qg) external switching MOSFETs. The driver exhibits low drain-to-source resistance (RDS(ON)) that decreases for lower operating temperatures. Lower RDS(ON) means higher source and sink currents from the device as the external MOSFET gate capacitance charges and discharges at a quicker rate, resulting in faster switching speeds. The peak source and sink current provided by the driver is 2.5A (typ). Propagation delay from the logic input (HI) to the driver output is 12ns (typ) (Figure 1). The internal driver also contains break-before-make logic to eliminate shootthrough conditions that cause unnecessarily high operating supply currents, efficiency reduction, and voltage spikes at VDD. Voltage from HDRV to LX is approximately equal to VDD minus the diode drop of the bootstrap diode when in a high state, and zero when in a low state.
Undervoltage Lockout
Connect an external Schottky diode between VDD and BST, in conjunction with an external bootstrap capacitor (CBST), to provide the voltage required to turn on the MOSFET (see the Typical Operating Circuits). The diode charges the bootstrap capacitor from VDD when the high-side switch is off, and isolates VDD when HDRV is pulled high when the driver turns on. The bootstrap capacitor (CBST) between BST and LX is used to ensure adequate charge is available to switch the high-side MOSFET. This capacitor is charged from VDD by an external bootstrap diode when the MOSFET is off. The bootstrap capacitor value should be selected carefully to avoid oscillations during turn-on and turnoff at the HDRV output. Choose a capacitor value at least 20 times greater than the total gate capacitance of the MOSFET being switched. Use a low-ESR ceramic capacitor (typically a minimum 0.1FF is needed). The high-side MOSFET's continuous on-time is limited due to the charge loss from the high-side driver's quiescent current. The maximum on-time is dependent on the size of CBST, IBST (125FA, max), and VBST_UVLO. The MAX15054 features a 5V CMOS logic input. The required logic-input levels are independent of VDD and are capable of withstanding up to 13.5V. For example, the MAX15054 can be powered by a 5V supply while the logic inputs are provided from 12V logic. Additionally, HI is protected against voltage spikes up to 15V, regardless of the VDD voltage. The logic input has 900mV hysteresis to avoid double pulsing during signal transition. The logic input is a high-impedance input (300kI, typ) and should not be left unconnected to ensure the input logic state is at a known level. With the logic input unconnected, HDRV pulls low as VDD rises above the UVLO threshold. The PWM output from the controller must assume a proper state while powering up the device.
Bootstrap Diode
MAX15054
Bootstrap Capacitor
Output Driver
Driver Logic Input (HI)
_______________________________________________________________________________________
7
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications MAX15054
Typical Operating Circuits (continued)
VIN VCC D1
VDD C1
BST CBST
GND
MAX15054
HDRV LX
Q1 L D2 Q2 C7 D3
HI R11 COUT
IN R1 C2 EN C3 R2
NDRV
CS
C6
R9 R10
R12
OVP
VCC C4 VCC R3 C5 VDRV
OUT1
OUT4
MAX16814
ISET R9
DIM FLAG R6 R5
LEDGND
RSDT R7 CC COMP RC RT R8 SGND PGND
8
______________________________________________________________________________________
High-Side MOSFET Driver for HB LED Drivers and DC-DC Applications
Pin Configuration
PROCESS: BiCMOS
___Chip Information
MAX15054
TOP VIEW
HI 1 + 6 LX
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. PACKAGE TYPE PACKAGE CODE U6+1 DOCUMENT NO. 21-0058 6 SOT23
GND 2
MAX15054
5
HDRV
VDD 3
4
BST
SOT23
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
(c)
9
2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.

▲Up To Search▲

Price & Availability of MAX15054AUT

	To Download MAX15054AUT Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .