LT1577 Linear Technology, LT1577 Datasheet
LT1577
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LT1577 Summary of contents
Page 1
... The LT1575 is available in 8-pin SO or PDIP and the LT1577 is available in 16-pin narrow body SO. , LTC and LT are registered trademarks of Linear Technology Corporation. UltraFast is a trademark of Linear Technology Corporation. ...
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... C/ W JMAX JA ORDER PART NUMBER LT1577CS-ADJ/ADJ TOP VIEW 1 16 SHDN1 IPOS1 INEG1 IN1 14 GND1 3 GATE1 13 OUT-3.3 4 COMP1 12 SHDN2 5 IPOS2 INEG2 IN2 10 GND2 7 GATE2 9 OUT-2.8 8 COMP2 S PACKAGE 16-LEAD PLASTIC NARROW 100 C, = 100 C/ W JMAX JA ORDER PART NUMBER LT1577CS-3.3/2.8 ...
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... IPOS 20V 3V IPOS 20V Current Flows Into Pin Current Flows Out of Pin Because the LT1577 consists of two regulators in the package, the total LT1577 power dissipation must be used for its junction temperature calculation. The total LT1577 P Note 3: The V of the external MOSFET must be greater than GS(th) 3V – ...
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... LT1575/LT1577 W U TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current vs Temperature 12V 20V –75 –50 – 100 125 150 TEMPERATURE ( C) 1575/77 G01 LT1575-1 Temperature OUT 1.515 1.512 1.509 1.506 1.503 1.500 1 ...
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... TEMPERATURE ( C) 0 – 0.1 – 0.2 IPOS = 20V – 0.3 – 0.4 – 0.5 –75 75 100 125 150 175 1575/77 G16 LT1575/LT1577 Gain and Phase vs Frequency 200 150 PHASE 100 GAIN 10k 100k 1M 150 175 FREQUENCY (Hz) 1575/77 G11 IPOS + INEG Supply Current vs Temperature ...
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... LT1575/LT1577 W U TYPICAL PERFORMANCE CHARACTERISTICS SHDN Sink Current vs Temperature 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 –75 – 50 – 100 125 150 175 TEMPERATURE ( C) 1575/77 G18 SHDN High Clamp Voltage vs Temperature 2.1 2.0 1.9 1.8 1.7 1.6 1.5 –75 – 50 – TEMPERATURE ( C) 6 SHDN Source Current vs Temperature –10 – 11 – 12 – 13 – 14 – ...
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... MOSFET. If this differential voltage is less than 0.5V, then the SHDN timer is not allowed to start even if the GATE is at the V normally as the input voltage is ramping up, even with very slow ramp rates. LT1575/LT1577 rail. This option provides the user with IN rail. This allows the regulator to start up IN ...
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... LT1575/LT1577 W BLOCK DIAGRAM SW1 NORMALLY SHDN OPEN SW2 NORMALLY CLOSED V IN START-UP GND FB 8 LT1575 Adjustable Voltage OR1 + COMP1 R2 – 100mV HYSTERESIS OR2 1.21V V REF I3 100 50k V TH1 50mV IPOS + I AMP INEG LIM – D1 – D2 COMP2 + + V TH2 ...
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... V IN START-UP V REF GND OUT R3* R4 R3/R4)V OUT REF LT1575 Fixed Voltage + COMP1 R2 – 100mV HYSTERESIS 1.21V Q7 I3 100 50k LT1575/LT1577 IPOS + V I AMP TH1 LIM INEG 50mV – – V COMP4 TH3 500mV + – COMP2 + + V TH2 COMP3 1V – + ...
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... LT1575-based solution achieves comparable efficiency performance with a switching regulator at an appreciable cost savings. The new LT1575/LT1577 family of low dropout regulator controller ICs step to the next level of performance re- quired by system designers for the latest generation motherboards and microprocessors. The simple versatil- ity and benefits derived from these circuits allow the power supply needs of today’ ...
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... This places the LT1575/LT1577 family among a select group of regulators with a very tightly specified output voltage tolerance. The accurate 1.21V reference is tied to the noninverting input of the main error amplifier in the feedback control loop ...
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... LT1575/LT1577 U U APPLICATIONS INFORMATION diagram and clamps the positive swing of the COMP node in the main error amplifier to a voltage that provides an output load current of 50mV/R SENSE ues as long as the output current overload persists. The second event is that a timer circuit activates at the SHDN pin ...
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... Note 69, “Using the LT1575 Linear Regulator Controller,” has been written and serves as an extremely useful guide for this new family of ICs. This Application Note covers topics including PC board layout for the LT1575/LT1577 family, MOSFET selection criteria, external component selection (capacitors) and loop compensation. Linear ...
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... LT1575/LT1577 U TYPICAL APPLICATIONS Setting Output Voltage with the Adjustable LT1575 V OUT 1.21V(1 + R2/R1) OUT 1575 TA03 Setting Current Limit IPOS SENSE INEG Q2 GATE V OUT *I = 50mV/R LIM SENSE R = DISCRETE SHUNT RESISTOR OR SENSE R = KELVIN-SENSED PC BOARD TRACE SENSE ACTIVATING CURRENT LIMIT ALSO ACTIVATES ...
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... TO 5.5V 4 12V 25mA 5 C3 4.7 F 100 4.75V TO 5.5V D2 BAT85 C9 D3 74HC14 0.22 F BAT85 C10 BAT85 390pF 0.22 F LT1575/LT1577 V TT 1.5V R8 R10 R11 R9 100 100 100 V REF R7 150 Q3 • • Q5 • 142 TOTAL SIGNAL LINES D1 L1 1N5818 33 H 12V 25mA LT1109CZ-12 ...
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... LT1575/LT1577 U TYPICAL APPLICATIONS + + + + C14 C11 C12 C13 150 F 150 F 150 F 150 F 16V 16V 16V 16V 9 EXTV OSC C8, 68pF 2 RUN/SS C7, 0 C10, 1000pF 4 SFB C9 1500pF 5 SGND 16.5k R8 15K 16 N 12V to 3.3V/9A (14A Peak) Hybrid Regulator 12V C6 0.1 F 12V C17 C15 ...
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... F U Dimensions in inches (millimeters) unless otherwise noted. N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 8 0.255 0.015* (6.477 0.381) 1 0.045 – 0.065 (1.143 – 1.651) 0.065 (1.651) TYP 0.100 0.010 (2.540 0.254) LT1575/LT1577 IRL3303 5 V CORE R1 2.8V 4.7k C5 ...
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... LT1575/LT1577 PACKAGE DESCRIPTION 0.010 – 0.020 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 – 0.050 0.406 – 1.270 * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" ...
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... DWG # 05-08-1610 0.228 – 0.244 (5.791 – 6.197 0.053 – 0.069 (1.346 – 1.752) 0 – 8 TYP 0.014 – 0.019 (0.355 – 0.483) LT1575/LT1577 0.386 – 0.394* (9.804 – 10.008 0.150 – 0.157** (3.810 – 3.988) 3 ...
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... Digitally Controlled Synchronous Switching Regulator Controller LT1573 Low Dropout Regulator Driver LT1580 7A, Very Low Dropout Linear Regulator LT1585-1.5 Fixed 1.5V, 5A Low Dropout Fast Response Regulator Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com LT1577 Split Plane System IRFZ24 R1 13 3 ...