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19-0186; Rev 2; 7/96
UAL IT MAN TION K SHEET VALUA E TA WS DA FOLLO
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters
____________________________Features
o 1V to 4.5V Input Guarantees Start-Up Under Load o Up to 210mA Output o Load Fully Disconnected in Shutdown o 82% Efficiency o Output in Regulation with Input Voltage above Output Voltage o Internal 1A Power Switch and Active Rectifier o Adjustable Current Limit Allows Low-Cost Inductors o 190A No Load Supply Current o 20A Shutdown Supply Current o 3V/3.3V (MAX778L), 5V (MAX777L), and Adjustable (MAX779L) Output Voltage
_______________General Description
The MAX777L/MAX778L/MAX779L are pulse-skipping DC-DC converters that step up from low-voltage inputs (1V guaranteed). They require only three external components--an inductor (typically 22H) and two capacitors. The MAX777L delivers a 5V output, the MAX778L generates pin-selectable voltages of 3.0V or 3.3V, and the MAX779L output can be adjusted from 2.5V to 6V through an external resistive divider. The devices include an Active RectifierTM that eliminates the need for an external catch diode, and permits regulation even when the input is greater than the output. Also, unlike those in other step-up converters, the MAX777L/MAX778L/MAX779L's Active RectifierTM turns off in the shutdown mode, disconnecting the output from the source. This eliminates the current drain associated with conventional step-up converters when off or in shutdown. High-frequency operation (up to 150kHz) allows the use of small, surface-mount inductors with values of 10H or less. Supply current is 190A under no load and only 20A in standby mode; supply voltage can range from 1V to 4.5V (1 to 3 cells). With a 2V input, the devices typically deliver 200mA at 5V, or 300mA at 3V. For fully specified devices designed for step-up/step-down applications (where the input can be above or below the output), refer to the MAX877L/MAX878L/MAX879L data sheet.
MAX777L/MAX778L/MAX779L
______________Ordering Information
PART MAX777LCPA MAX777LCSA MAX777LC/D MAX777LEPA MAX777LESA MAX777LMJA TEMP. RANGE 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C PIN-PACKAGE 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP**
________________________Applications
Single Battery-Cell (1V), Step-Up Voltage Conversion Efficient, High-Power Step-Up Regulation from Low Input Voltages Pagers Portable Instruments & Hand-Held Terminals Notebook and Palmtop Computers
Ordering Information continued at end of data sheet. * Dice are specified at TA = +25C, DC parameters only. **Contact factory for availability and processing to MIL-STD-883.
__________Typical Operating Circuit
INPUT 1V TO 4.5V
2
__________________Pin Configuration
TOP VIEW
22F
IN ILIM MAX777L SHDN PGND 4 LX OUT AGND 3 5 6
22H
ILIM 1 IN 2
8
N.C. (MAX777L)* SHDN OUT LX
1 7
ON/OFF
OUTPUT 5V
100F
AGND 3 PGND 4
MAX777L MAX778L MAX779L
7 6 5
DIP/SO * SEL FOR MAX778L, FB FOR MAX779L.
Active Rectifier is a trademark of Maxim Integrated Products.
________________________________________________________________ Maxim Integrated Products 1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (IN to PGND).......................................0V to 4.5V Output Short-Circuit Duration to PGND, AGND (Note 1)....30sec Voltage Applied to: LX (switch off) .......................................................-0.3V to 4.5V (switch on) ....................................30sec short to IN or OUT OUT, SHDN ...........................................................-0.3V to +7V FB ...........................................................-0.3V to (OUT + 0.3V) AGND to PGND ........................................................-0.3V, +0.3V Reverse Battery Current....................................................900mA Continuous Power Dissipation (TA = +70C) Plastic DIP (derate 9.09mW/C above +70C) .............727mW SO (derate 5.88mW/C above +70C) ..........................471mW CERDIP (derate 8.00mW/C above +70C) ..................640mW Operating Temperature Ranges: MAX77_LC_A .......................................................0C to +70C MAX77_LE_A ....................................................-40C to +85C MAX77_LMJA .................................................-55C to +125C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10sec) .............................+300C
Note 1: The output may be shorted to ground if the package power dissipation is not exceeded.
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 = +2.5V, ILOAD = 0mA, L = 22H, COUT = 100F, SHDN and ILIM connected to IN, AGND connected to PGND, TA = TMIN to TMAX, typical values are at TA = +25C, unless otherwise noted.) PARAMETER Minimum Start-Up Voltage CONDITIONS ILOAD < 10mA, TA = +25C (Note 2) MAX777LC/ MAX779LC MAX777LE/ MAX779LE MAX777LM/ MAX779LM MAX778LC SEL = 0V Output Voltage MAX778L (Note 6) SEL = OPEN MAX778LE MAX778LM MAX778LC MAX778LE MAX778LM Output Voltage Range (MAX779L) Efficiency No-Load Supply Current Shutdown Supply Current SHDN Input Current (Note 4) ILOAD = 100mA ILOAD = 0mA (switch off) SHDN = 0V MAX77_LC, MAX77_LE MAX77_LM ILOAD 30mA, 1.1V VIN 4.5V or ILOAD 140mA, 1.8V VIN 4.5V ILOAD 30mA, 1.2V VIN 4.5V or ILOAD 130mA, 1.8V VIN 4.5V ILOAD 25mA, 1.25V VIN 4.5V or ILOAD 120mA, 1.8V VIN 4.5V ILOAD 50mA, 1.1V VIN 3.3V or ILOAD 210mA, 1.8V VIN 3.3V ILOAD 50mA, 1.2V VIN 3.3V or ILOAD 200mA, 1.8V VIN 3.3V ILOAD 50mA, 1.25V VIN 3.3V or ILOAD 180mA, 1.8V VIN 3.3V ILOAD 50mA, 1.1V VIN 3V or ILOAD 210mA, 1.8V VIN 3V ILOAD 50mA, 1.2V VIN 3V or ILOAD 200mA, 1.8V VIN 3V ILOAD 40mA, 1.25V VIN 3V or ILOAD 180mA, 1.8V VIN 3V MIN 4.5 TYP MAX UNITS 1 V V
Maximum Operating Voltage (Notes 2, 3) Output Voltage MAX777L/MAX779L (set to 5V) (Note 6)
4.80
5.00
5.20
V
3.17
3.30
3.43
V
2.88
3.00
3.12
2.5 82 190 20 20 15 12
6.0
V %
310 30 35 100 40
A A nA A
0V < SHDN < VIN VIN < SHDN < 5V
2
_______________________________________________________________________________________
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters
ELECTRICAL CHARACTERISTICS (continued)
(VIN = +2.5V, ILOAD = 0mA, L = 22H, COUT = 100F, SHDN and ILIM connected to IN, AGND connected to PGND, TA = TMIN to TMAX, typical values are at TA = +25C, unless otherwise noted.) PARAMETER SHDN Threshold SHDN Enable Delay Current Limit Current-Limit Temperature Coefficient ISW = 400mA Switch Saturation Voltage ISW = 600mA ISW = 1000mA VIN = 2.5V Maximum Switch On Time VIN = 1.8V VIN = 1V Minimum Switch Off Time MAX777L, MAX779L MAX778 ISW = 400mA Rectifier Forward Voltage Drop Error-Comparator Trip Point FB Pin Bias Current Switch Off Leakage Current Rectifier Off Leakage Current ISW = 600mA ISW = 1000mA MAX779L, over operating input voltage (Note 5) MAX779L, VFB = 0.3V 197.5 VIN = 1V to 4.5V VIN = 2.5V 1.20 150 1.0 -0.3 0.275 0.33 0.50 4.0 5.9 12.6 1.2 2.2 0.21 0.31 0.50 202.5 10 0.1 0.1 207.5 40 mV nA A A V s s V CONDITIONS MIN TYP VIN/2 + 0.25 1.6 MAX UNITS V s A %/C
MAX777L/MAX778L/MAX779L
Note 2: Output in regulation, VOUT = VOUT (nominal) 4%. Note 3: At high VIN to VOUT differentials, the maximum load current is limited by the maximum allowable power dissipation in the package (see Absolute Maximum Ratings). Note 4: Minimum value is production tested. Maximum value is guaranteed by design and is not production tested. Note 5: VOUT is set to a target value of +5V by 0.1% external feedback resistors. VOUT is measured to be 5V 2.5% to guarantee the error comparator trip point. Note 6: Start-Up guaranteed under these load conditions.
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3
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
__________________________________________Typical Operating Characteristics
(Typical Operating Circuit, TA = +25C, unless otherwise noted).
MAX778L SHDN THRESHOLD VOLTAGE vs. INPUT VOLTAGE AND TEMPERATURE
MAX777-8
NO-LOAD SUPPLY CURRENT vs. VOLTAGE AND TEMPERATURE
MAX777-6
SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE AND TEMPERATURE
70 60 50 40 30 20 10 0 1 2 3 TA = 0C TA = -40C 4 5 6 7 TA = +85C
MAX777-7
300 280 NO-LOAD SUPPLY CURRENT (A) 260 240 220 200 180 160 140 120 100 1
(SWITCH = OFF) TA = +85C
80 SHUTDOWN SUPPLY CURRENT (A)
3.5 SHDN THRESHOLD VOLTAGE (V) 3.0 2.5 2.0 1.5 1.0 TA = -55C 0.5 1 2 3 4 5 6 7 TA = +25C
TA = +125C
TA = +25C TA = -40C 2 3
TA = 0C 4 5 6 7
SUPPLY VOLTAGE (V)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
MAX777L/MAX779L EFFICIENCY vs. LOAD CURRENT
MAX777-1
MAX778L EFFICIENCY vs. LOAD CURRENT
VOUT = 3.3V OR 3.0V 80 EFFICIENCY (%) 70 60 50 40 30 0.1
MAX777-2
90 VOUT = 5V 80 EFFICIENCY (%) 70 60 50 40 30 0.1 VIN = 4V VIN = 2.5V VIN = 1.8V VIN = 1.5V VIN = 1.1V 1 10 100
90
VIN = 2.5V VIN = 1.8V VIN = 1.5V VIN = 1.1V 1 10 100 1000
1000
LOAD CURRENT (mA)
LOAD CURRENT (mA)
MAX777L/MAX779L MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE
MAX777-4
MAX778L MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE
VOUT = 3.3V 300 OUTPUT CURRENT (mA) 250 200 150 100 50 0 0.5
MAX777-5
300 VOUT = 5V 250 OUTPUT CURRENT (mA) 200 150 100 50 0 0.5
350
1.0
1.5
2.0
2.5
1.0
1.5
2.0
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
4
_______________________________________________________________________________________
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters
_____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 1, TA = +25C, unless otherwise noted.) LOAD-TRANSIENT RESPONSE LINE-TRANSIENT RESPONSE
MAX777L/MAX778L/MAX779L
A
A
B
B
2ms/div A: IOUT, 200mA/div, 0mA to 200mA B: VOUT, 50mV/div, AC COUPLED MAX778L, VOUT = 3.3V, VIN = 2.5V
2ms/div A: VIN, 1V/div, 1.8V to 3.3V B: VOUT, 100mV/div, AC-COUPLED, IOUT = 240mA MAX778L, VOUT = 3.3V
SWITCHING WAVEFORMS, CONTINUOUS CONDUCTION
SWITCHING WAVEFORMS, DISCONTINUOUS CONDUCTION
A
A
B 0mA C 5s/div A: SWITCH VOLTAGE (LX PIN), 2V/div B: INDUCTOR CURRENT, 0.5A/div C: OUTPUT VOLTAGE RIPPLE, 50mV/div, AC COUPLED MAX777L, VIN = 1.5V, IOUT = 100mA B C
2s/div A: SWITCH VOLTAGE (LX PIN), 2V/div B: INDUCTOR CURRENT, 0.5A/div C: OUTPUT VOLTAGE RIPPLE, 50mV/div, AC COUPLED MAX777L, VIN = 3V, IOUT = 70mA
_______________________________________________________________________________________
5
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
_____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 1, TA = +25C, unless otherwise noted.)
MAX778L START-UP TIME
A
B
10ms/div A: SHDN, 2V/div B: VOUT, 1V/div VOUT = 3V
______________________________________________________________Pin Description
PIN NAME ILIM IN AGND PGND LX OUT SHDN N.C. (MAX777L) 8 SEL (MAX778L) FB (MAX779L) 6 FUNCTION Sets switch current-limit input. Connect to IN for 1A current limit. A resistor from ILIM to IN sets lower peak inductor currents. Input from battery Analog ground. Not internally connected to PGND. Power ground. Must be low impedance; solder directly to ground plane or star ground. Connect to AGND, close to the device. Collector of 1A NPN power switch and emitter of Active Rectifier PNP. Voltage output. Connect filter capacitor close to pin. Shutdown input disables power supply when low. Also disconnects load from input. Threshold is set at VIN/2. No connect--not internally connected. Selects the main output voltage. 3.3V when hard-wired to AGND, 3.0V when left open. Feedback input for adjustable-output operation. Connect to an external voltage divider between VOUT and AGND.
1
2 3 4 5 6 7
_______________________________________________________________________________________
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
22H VIN 100F RLIM 2 IN DELAY TIMER tOFF SWITCH DRIVER RECTIFIER CONTROL PGND 4 1 : N ILIM 1 LX
ACTIVE RECTIFIER
OUT 6
VOUT 100F
DELAY TIMER tON
MAX778L
SEL 8 VREF 7 SHDN SHUTDOWN CONTROL AGND 3 0.2025V
Figure 1. MAX778L Block Diagram
_______________Detailed Description
Operating Principle
The MAX777L/MAX778L/MAX779L combine a switchmode regulator with an NPN bipolar switch, current limit, precision voltage reference, and active rectifier-- all in a single monolithic device. In shutdown mode, the internal rectifier is completely turned off and disconnects the load from the source. Only two external components are required in addition to the input bypass capacitor: a 22H inductor and a 100F filter capacitor. A minimum off-time, current-limited, pulse-frequencymodulation (PFM) control scheme combines the advantages of pulse width modulation (PWM) (high output power and efficiency) with those of a traditional PFM pulse skipper (low quiescent currents). External conditions (inductor value, load, and input voltage) determine the way the converter operates, as follows:
At light loads, the current through the inductor starts at zero, rises to a peak value, and drops down to zero in each cycle (discontinuous-conduction mode). In this case, the switching frequency is governed by a pair of one-shots that set a maximum on-time inversely proportional to VIN [tON = 8.8/(VIN - 0.25)] and a minimum offtime (1.3s for MAX777L/MAX779L and 2.3s for MAX778L). With a 22H inductor, LX's peak current is about 400mA and is independent of input voltage. Efficiency at light loads is improved because of lower peak currents. At very light loads, more energy is stored in the coil than is required by the load in each cycle. The converter regulates by skipping entire cycles. Efficiency is typically 65% to 75% in the pulse-skipping mode. Pulse-skipping waveforms can be irregular, and the output waveform contains a low-frequency component. Larger, low equivalent series resistance (ESR) filter capacitors can help reduce the ripple voltage if needed.
_______________________________________________________________________________________
7
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
At heavy loads above approximately 100mA, the converter enters continuous-conduction mode, where current always flows in the inductor. The switch-on state is controlled cycle-by-cycle by either the maximum t ON time or the switch's preset current limit. As a result, the switch's current rating is not exceeded and the inductor is not saturated. At very heavy loads, the inductor current self-oscillates between this peak current limit and some lower value governed by the minimum off-time, the inductance value, and the input/output differential. With ILIM shorted to IN, the peak switch current of the internal NPN power switch is set to 1A. The peak switch current can be set to a lower value by connecting a resistor between ILIM and IN (see Current Limit section). This enables the use of physically smaller inductors with lower saturation-current ratings. At 1A, the switch voltage drop (V SW ) is about 500mV. V SW decreases to about 250mV at 0.1A. Conventional PWM converters generate constant-frequency switching noise, while this architecture produces variable-frequency switching noise. However, the noise does not exceed the current limit times the filter-capacitor ESR, unlike conventional pulse-skippers. converters. Useful in battery-powered applications, where the battery voltage may initially exceed the output voltage, the converters will regulate down to the output voltage and seamlessly switch into boost mode as the input drops below the output voltage. The pin-compatible MAX877L/MAX878L/MAX879L are fully specified buck/boost converters with higher specified output currents than the MAX777L/MAX778L/MAX779L.
Shutdown Shutdown (SHDN) is a high-impedance, active-low input. Connect SHDN to V IN for normal operation. Keeping SHDN at ground holds the converters in shutdown mode. Since the active rectifier is turned off in shutdown mode, the path from input to load is cut, and the output effectively drops to 0V. The supply current in the shutdown state ranges from 4A at VIN = 1V to 50A at VIN = 4.5V. The shutdown circuit threshold is set nominally to VIN/2 + 250mV. When SHDN is below this threshold, the device is shut down and is enabled with SHDN above the threshold. When driven from external logic, SHDN can be driven to a higher voltage than VIN. Current Limit Connecting ILIM to IN sets an LX current limit of 1A. For smaller output power levels that do not require the maximum peak current, the peak inductor current can be reduced to optimize overall efficiency and to allow very small, low-cost coils with lower current ratings. See also the Inductor Selection section. Reduce the MAX777L/MAX778L/MAX779L peak inductor current by connecting a resistor between ILIM and IN. See Figure 2 to select the resistor.
CURRENT-LIMIT RESISTOR vs. PEAK INDUCTOR CURRENT
MAX777-FG02
Step-Down Mode
If the input voltage exceeds the output voltage, the MAX777L/MAX778L/MAX779L behave as "switched" linear regulators. If the output voltage starts to drop, the switch turns on and energy is stored in the coil, as in normal step-up mode. After the switch turns off, the voltage at LX flies high. The active rectifier turns on when LX rises above VIN. As in a linear regulator, the voltage difference between V IN and V OUT appears across the rectifier (actually a PNP transistor) until the current goes to zero and the rectifier turns off. At high VIN to VOUT differentials, the maximum load current is limited by the maximum allowable power dissipation in the package. For fully specified buck/boost converters, refer to the data sheet for the pin-compatible MAX877L/MAX878L/MAX879L.
1200 PEAK INDUCTOR CURRENT (mA) 1000 800 600 400 VIN = 2.5V 200 0 0 2 4 6 8 10 12
Active Rectifier
The internal active rectifier of the MAX777L/MAX778L/ MAX779L replaces the external Schottky catch diode in normal boost operation. The rectifier consists of a PNP pass transistor and a unique control circuit which, in shutdown mode, entirely disconnects the load from the source. This is a distinct advantage over standard boost topologies, since it prevents battery drain in shutdown. The active rectifier also acts as a zero-dropout regulator if the input exceeds the regulated output. This allows the MAX777L/MAX778L/MAX779L to act as buck/boost
8
14
RESISTOR VALUE (k)
Figure 2. Current-Limit Resistor vs. Current Limit
_______________________________________________________________________________________
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters
Inductor Selection
VIN C1 22F 2 IN LI 22H
MAX777L/MAX778L/MAX779L
5 LX OUT 6 VOUT
7
MAX779L
SHDN
R1 8
C3
C2 100F
1
ILIM AGND 3
FB PGND 4
The 22H inductor shown in the Typical Operating Circuit is sufficient for most MAX777L/MAX778L/ MAX779L designs. Other inductor values ranging from 10H to 47H are also suitable. The inductor should have a saturation rating equal to or greater than the peak switch-current limit, which is 1A without an external current limit (ILIM connected to IN). It is acceptable to operate the inductor at 120% of its saturation rating; however, this will reduce efficiency. For highest efficiency, use an inductor with a low DC resistance, preferably under 0.2. Table 1 lists suggested inductor suppliers.
R2
Capacitor Selection
The 100F, 10V surface-mount tantalum (SMT) output capacitor shown in the Typical Operating Circuit will provide a 20mV output ripple or less, stepping up from 2V to 3.3V at 200mA. Smaller capacitors, down to 10F, are acceptable for light loads or in applications that tolerate higher output ripple. The input capacitor may be omitted if the input lead length is less than 2 inches (5cm) or if the loads are small. The primary factor in selecting both the output and input filter capacitor is low ESR. The ESR of both bypass and filter capacitors affects efficiency. Optimize performance by increasing filter capacitors or using specialized low-ESR capacitors. The smallest low-ESR SMT tantalum capacitors currently available are Sprague 595D or 695D series. Sanyo OS-CON organic semiconductor through-hole capacitors also exhibit very low ESR, are rated for the wide temperature range, and are particularly useful for operation at cold temperatures. Table 1 lists suggested capacitor suppliers.
Figure 3. MAX779L Adjustable Voltage
Output Voltage Selection
The output voltage of the MAX777L is fixed at 5V. The MAX778L output voltage can be set to 3V by leaving the SEL pin open. Connect SEL to AGND for 3.3V operation. The MAX779L's output voltage is set by two resistors, R1 and R2 (Figure 3), which form a voltage divider between the output and the FB pin. The output voltage can be set from 2.5V to 6.0V by the equation: VOUT = (0.2025) [(R1 + R2)/R2] To simplify the resistor selection: R1 = (R2)[(VOUT/0.2025) - 1] Since the input current at FB is 40nA maximum, large values (10k to 50k for R2) can be used with no significant loss of accuracy. For 1% error, the current through R2 should be at least 100 times FB's bias current. When large values are used for the feedback resistors (R1 > 50k), stray output impedance at FB can add "lag" to the feedback response, destabilizing the regulator and creating a larger ripple at the output. Lead lengths and circuit board traces at the FB node should be kept short. Reduce ripple by adding a "lead" compensation capacitor (C3, 100pF to 50nF) in parallel with R1.
Layout
The MAX777L/MAX778L/MAX779L's high peak currents and high-frequency operation make PC layout important for minimum ground bounce and noise. Locate input bypass and output filter capacitors close to the device pins. All connections to the FB pin (MAX779L) should also be kept as short as possible. A ground plane is recommended. Solder AGND (pin 3) and PGND (pin 4), directly to the ground plane. Refer to the MAX777L/MAX778L/MAX779L evaluation kit (EV kit) manual for a suggested surface-mount layout.
__________Applications Information
The Typical Operating Circuit shows a MAX777L stepup application circuit. This circuit starts up and operates with inputs ranging from 1.0V to 4.5V. Start-up time is a function of the load, typically less than 5ms. Output current capability is a function of the input voltage. See Typical Operating Characteristics.
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9
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
Table 1. Component Suppliers
PRODUCTION METHOD INDUCTORS Sumida CD54-220 (22H) Murata-Erie LQHYN1501K04M00-D5 (15H) Coiltronics CTX20-1 Miniature Through-Hole Sumida RCH654-220 CAPACITORS Sprague 595D Sprague 695D Surface Mount Matsuo 267 series AVX TPS series Sanyo OS-CON low-ESR organic semiconductor Nichicon PL series low-ESR electrolytic United Chemi-Con, LXF series
Low-Cost Through-Hole
Coilcraft PCH-27-223
AVX Coiltronics Matsuo Murata-Erie Nichicon Sanyo Sprague Sumida United Chemi-Con
USA: USA: USA: USA: USA: USA: Japan: USA: USA: Japan: USA:
(803) 946-0690 (800) 282-4975, FAX (803) 626-3123 (561) 241-7876, FAX (561) 241-9339 (714) 969-2491, FAX (714) 960-6492 (814) 237-1431 (800) 831-9172, FAX (814) 238-0490 (847) 843-7500 (619) 661-6835, FAX (847) 843-2798 (81) 7-2070-6306, FAX (81) 7-2070-1174 (603) 224-1961, FAX (603) 224-1430 (847) 956-0666, FAX (847) 956-0702 (81) 3-3607-5111, FAX (81) 3-3607-5144 (714) 255-9500, FAX (714) 255-9400
10
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Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters
_Ordering Information (continued)
PART MAX778LCPA MAX778LCSA MAX778LC/D MAX778LEPA MAX778LESA MAX778LMJA MAX779LCPA MAX779LCSA MAX779LC/D MAX779LEPA MAX779LESA MAX779LMJA TEMP. RANGE 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C PIN-PACKAGE 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP** 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP**
PGND OUT IN ILIM VREF FB
___________________Chip Topography
MAX777L/MAX778L/MAX779L
SHDN
AGND
0.084" (2.134mm)
* Dice are specified at TA = +25C, DC parameters only. **Contact factory for availability and processing to MIL-STD-883.
LX 0.068" (1.727mm)
TRANSISTOR COUNT: 170; SUBSTRATE CONNECTED TO AGND.
______________________________________________________________________________________
11
Low-Voltage Input, 3V/3.3V/5V/ Adjustable Output, Step-Up DC-DC Converters MAX777L/MAX778L/MAX779L
________________________________________________________Package Information
E D A3 A A2 E1
DIM A A1 A2 A3 B B1 C D1 E E1 e eA eB L INCHES MAX MIN 0.200 - - 0.015 0.175 0.125 0.080 0.055 0.022 0.016 0.065 0.045 0.012 0.008 0.080 0.005 0.325 0.300 0.310 0.240 - 0.100 - 0.300 0.400 - 0.150 0.115 INCHES MIN MAX 0.348 0.390 0.735 0.765 0.745 0.765 0.885 0.915 1.015 1.045 1.14 1.265 MILLIMETERS MIN MAX - 5.08 0.38 - 3.18 4.45 1.40 2.03 0.41 0.56 1.14 1.65 0.20 0.30 0.13 2.03 7.62 8.26 6.10 7.87 2.54 - 7.62 - - 10.16 2.92 3.81 MILLIMETERS MIN MAX 8.84 9.91 18.67 19.43 18.92 19.43 22.48 23.24 25.78 26.54 28.96 32.13
21-0043A
L A1 e B D1
0 - 15 C B1 eA eB
Plastic DIP PLASTIC DUAL-IN-LINE PACKAGE (0.300 in.)
PKG. DIM PINS P P P P P N D D D D D D 8 14 16 18 20 24
DIM
D A e B
0.101mm 0.004in.
0-8
A1
C
L
A A1 B C E e H L
INCHES MAX MIN 0.069 0.053 0.010 0.004 0.019 0.014 0.010 0.007 0.157 0.150 0.050 0.244 0.228 0.050 0.016
MILLIMETERS MIN MAX 1.35 1.75 0.10 0.25 0.35 0.49 0.19 0.25 3.80 4.00 1.27 5.80 6.20 0.40 1.27
E
H
Narrow SO SMALL-OUTLINE PACKAGE (0.150 in.)
DIM PINS D D D 8 14 16
INCHES MILLIMETERS MIN MAX MIN MAX 0.189 0.197 4.80 5.00 0.337 0.344 8.55 8.75 0.386 0.394 9.80 10.00
21-0041A
12
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