LTC1174-3.3 Linear Technology, LTC1174-3.3 Datasheet
LTC1174-3.3
Related parts for LTC1174-3.3
LTC1174-3.3 Summary of contents
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... LTC are registered trademarks and trademark of Linear Technology Corporation 25V 5V 175mA † 100 H + 100 F** 1N5818 10V 1174 TA01 LTC1174 LTC1174-3.3/LTC1174-5 High Efficiency DC/DC Converter U 1174 is a simple current mode DC/DC converter switch (at a supply LTC1174-5 Efficiency 100 ...
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... SHUTDOWN CONDITIONS LTC1174/LTC1174HV LTC1174/LTC1174HV LTC1174-3.3/LTC1174HV-3.3 LTC1174-5/LTC1174HV 12V 100mA (Note 2) IN LOAD PGM IN LTC1174-3.3 (Note 2) 20mA < I < 175mA LOAD PGM 20mA < I < 400mA LOAD PGM IN LTC1174-5 (Note 2) 20mA < I < 175mA LOAD PGM 20mA < I < ...
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... Note 4: Current into pin 6 only, measured without electrolytic input capacitor. Note 5: The off-time is wafer-sort trimmed. Note 6: The LTC1174I is not tested and not quality assurance sampled at – and 85 C. These specifications are guaranteed by design and/or correlation. LTC1174 LTC1174-3.3/LTC1174 0V, unless otherwise noted. IN PGM MIN ...
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... LTC1174 LTC1174-3.3/LTC1174 TYPICAL PERFOR A Efficiency vs Load Current 100 OUT PGM COIL = CTX50 100 200 LOAD CURRENT (mA) 1174 G01 Efficiency vs Load Current 100 3.3V OUT ...
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... PI FU CTIO (Pin 1): For the LTC1174, this pin connects to the OUT FB main voltage comparator’s input. On the LTC1174-3.3 and LTC1174-5 this pin goes to an internal resistive divider which sets the output voltage. LB (Pin 2): Open Drain of an N-Channel Pull-Down. This OUT pin will sink current when pin 3 (LB During shutdown this pin goes to high impedance ...
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... During the switch“ON” time, switch current flows through the 0.1 sense resistor. When this current reaches the threshold of the current comparator A2, its output signal will change state, setting the flip-flop and turning the switch off (Pin 1 connection shown for LTC1174-3.3 and LTC1174-5, changes create LTC1174 SLEEP – ...
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... Inductor Core Selection section) due to higher ripple current prevent OUT IN Figure 1. Efficiency Using Different Types of Inductor Core Material LTC1174 LTC1174-3.3/LTC1174 and V is the voltage drop across the diode OUT ...
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... LTC1174 LTC1174-3.3/LTC1174 PPLICATI S I FOR ATIO the maximum RMS current must be used. The C current is given by OUT OUT IN OUT I RMS V IN This formula has a maximum /2. This simple worst case is commonly used for design OUT because even significant deviations do not offer much relief. Note that ripple current directly affects capacitor’ ...
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... Is the SHUTDOWN (pin 8) actively pulled to V normal operation? The SHUTDOWN pin is high imped- ance and must not be allowed to float the I PGM I pin is high impedance and must not be allowed PGM to float. LTC1174 LTC1174-3.3/LTC1174-5 INPUT VOLTAGE 4V TO 12V + + 0 16V ...
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... LTC1174 LTC1174-3.3/LTC1174 PPLICATI S I FOR ATIO OUTPUT DIVIDER REQUIRED WITH ADJUSTABLE VERSION ONLY Figure 6. LTC1174 Layout Diagram (See Board Layout Checklist) DESIGN EXAMPLE As a design example, assume (nominal 5V, and I = 350mA maximum. The LTC1174-5 is used OUT for this application, with I ...
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... GND 47.5k High Efficiency 3.3V Regulator + SHUTDOWN PGM OUT LTC1174-3 OUT GND 1N5818 4 LTC1174 LTC1174-3.3/LTC1174-5 PART NUMBER TPS Series TAJ Series PL Series OS-CON Series + F** 16V IN 8 SHUTDOWN 1 V OUT V OUT † L1 365mA + 2 ...
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... LTC1174 LTC1174-3.3/LTC1174 TYPICAL A PPLICATI INPUT VOLTAGE 4V TO 12.5V AVX TPSD226K025 * AVX TPSD105K010 ** † COILTRONICS CTX50-4 * LOW-BATTERY INDICATOR SET TO TRIP 4. AVX TPSD106K035 6 *** AVX TPSD105K010 MBRS130LT3 (SURFACE MOUNT) 10 1N5818 12.5 † L1 SELECTION MANUFACTURER PART NO. TYPE COILTRONICS CTX50-3 SURFACE MOUNT ...
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... LCD Display Power Supply SHUTDOWN PGM FB LTC1174 OUT GND F** 0.1 F 16V LTC1174 LTC1174-3.3/LTC1174-5 310k + 0.1 F 0.1 F 50k † INPUT VOLTAGE –5V 0 OUT IN LT1121-5 †† 110k 5 + SHUTDOWN 0.1 F GND †† ...
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... LTC1174 LTC1174-3.3/LTC1174 TYPICAL PPLICATI SANYO OS-CON * WIMA MKS2 ** † COILTRONICS CTX100-4 V (V) I (mA) IN OUT MAX 100 8 125 10 145 12 160 13 180 3 2 CTX100-4 L1A L1B AVX TAJD226K035 ** WIMA MKS2 † COILTRONICS CTX100-4 †† USE 1% METAL FILM RESISTORS ...
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... OUT MAX 6 320 325 V IN 330 SHUTDOWN PGM 335 335 LTC1174 OUT GND 4 LTC1174 LTC1174-3.3/LTC1174-5 V † OUT 0mA TO 320mA + 100k 100 F* 1N5818 16V 36.5k 1174 TA13 + 100 F* 0.1 F 20V V OUT 5V † L1A 160mA 100 H + ...
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... LTC1174 LTC1174-3.3/LTC1174-5 PACKAGE DESCRIPTIO 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) +0.025 0.325 –0.015 +0.635 8.255 –0.381 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTURSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm). ...