LTC1433 Linear Technology, LTC1433 Datasheet
LTC1433
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LTC1433 Summary of contents
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... The LTC1433/LTC1434 are capable of supplying up to 450mA of output current and boasts a 2.4% output voltage accuracy. An internal low-battery detector has the same level of accuracy as the output voltage. A power-on ...
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... Commercial Temperature Range LTC1433C/LTC1434C .............................. – 13.5V) IN Extended Commercial Operating Temperature Range (Note 2) ....................................... – Industrial Temperature Range (Note 3) LTC1433I/LTC1434I ........................... – – 13.5V) IN Junction Temperature (Note 4)............................. 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 ...
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... T J dissipation P according to the following formula: D LTC1433/LTC1434: T Note 5: The LTC1433/LTC1434 are tested in a feedback loop which servos V to the feedback point for the error amplifier (V OSENSE Note 6: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. ...
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... LTC1433/LTC1434 W U TYPICAL PERFORMANCE CHARACTERISTICS Efficiency of Figure 1 for 100 12V 3.3V OUT 47pF SOC 40 0.001 0.01 0.1 LOAD CURRENT (A) 1433/34 G01 Dropout Characteristics at Different Load Currents (V = 5V) OUT 5.1 5.0 I OUT 4.9 200mA I 4.8 OUT 400mA 4.7 I OUT 4.6 300mA 4.5 4 PROG ...
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... Supply for the Internal Power IN MOSFETs and Switch Drivers. Must decouple this pin properly to ground. NC (Pins 2, 4,/Pins 8): No Connection. pin determines 3.3V OUT OUT V = Adjustable OUT LTC1433/LTC1434 16 (65536) oscillator cycles. The POR . OUT . Anode of the Schottky diode must IN 5 ...
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... U OPERATION (Refer to Functional Diagram) Main Control Loop The LTC1433/LTC1434 is a constant frequency, pulse- width modulated current mode switching regulator. Dur- ing normal operation, the internal P-channel power MOSFET is turned on each cycle when the oscillator sets the RS latch FF3, and turned off when the main current compara- tor I resets the latch ...
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... OSC C OSC A graph for selecting C is OSC 2. For the LTC1433, the expression above is also appli- cable since its oscillator is internally set up to run at a condition equal to V graph for determining the capacitance value for the oscil- lator frequency, the V LTC1433. LTC1433/LTC1434 16 (65536) oscillator cycles ...
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... Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the LTC1433/LTC1434 are used at 100% duty cycle with low input voltages. Inductor Value Calculation The operating frequency and inductor selection are inter- related in that higher operating frequencies permit the use = 1 ...
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... The output ripple ( V V OUT where f = operating frequency, C and I = ripple current in the inductor. The output ripple L is highest at maximum input voltage since I with input voltage. For the LTC1433/LTC1434, the general rule for proper operation is: approaches V IN OUT C required ESR < 0.25 OUT Manufacturers such as Nichicon, United Chemicon and Sanyo should be considered for high performance through-hole capacitors ...
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... Hence, the dual inductor configuration is good for the user who requires as high an efficiency as possible at low load while retaining constant frequency operation. Output Voltage Programming The LTC1433/LTC1434 family all have pin selectable out- put voltage programming. The output voltage is selected by the V PROG ...
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... Run/Soft Start Function The RUN/SS pin is a dual purpose pin which provides the soft start function and a means to shut down the LTC1433/ LTC1434. Soft start reduces input surge currents by providing a gradual ramp-up of the internal current limit. ...
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... OSC LP Low-Battery Comparator C OSC The LTC1433/LTC1434 have an on-chip, low-battery com- parator which can be used to sense a low-battery condi- tion when implemented as shown in Figure 12. The resis- OSC tor divider R3/R4 sets the comparator trip point as follows: V LBTRIP 1433/34 F10 The divided down voltage at the negative (–) input to the comparator is compared to an internal 1 ...
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... PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1433/LTC1434. These items are also illustrated graphi- cally in the layout diagram of Figure 13. Check the follow- ing in your layout: 1. Are the signal and power grounds segregated? The LTC1433/LTC1434 signal ground pin must return to the (– ...
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... MOSFET, preventing a large amount of current from flowing into the substrate to create a potential latchup condition. 100 F* 0.1 F 10V PWRV PGND 10k LTC1433 13 C OSC 12 POWER-ON POR RESET 680pF 5.1k V OSENSE 50pF 9 V ...
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... NC C OSC 5 12 SGND POR 6800pF 6 11 RUN/ 0.01 F LBO V OSENSE 8 9 LBI V PROG 680pF * AVX TPSD107M010R0100 ** AVX TPSE107M016R0100 LTC1433/LTC1434 V IN 3.5V TO 12.5V FOR 12.5V FOR V 68 F** OUT 0.1 F 20V 100k POWER-ON RESET 5.1k 680pF = 3.3V OUT = 5V OUT 6800pF 1433/34 TA02 V IN 3.5V TO 7.5V + 100 F** 0.1 F 16V ...
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... NC C OSC 5 SGND POR 6 RUN/ LBO V 0.1 F OSENSE 8 LBI V PROG * AVX TPSE107M016R0100 ** AVX TPSE686M020R0150 0 SSW PWRV PGND BSW SV + LTC1433 4 100 10V 5 SGND POR 6 23.8k RUN/ 0.1 F LBO V OSENSE 1.2k 8 LBI V PROG 1% 310k 1% 16 50k 100pF ...
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... PROG 30k 100k LOW-BATTERY TRIP 96k L1A EACH OUTPUT OUT(MAX) 4.5 • 5.0 1 6.0 L1A 7.0 8.0 9.0 PART NO. 10.0 11.0 CTX100-4 12.0 LPT4545-101LA 12.5 LTC1433/LTC1434 V + 4.5V TO 12. 0.1 F 20V 100k 50pF POWER-ON RESET 680pF 1k 6800pF 1433/34 TA07 (mA 100 110 130 145 160 200 205 IN 17 ...
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... LTC1433/LTC1434 PACKAGE DESCRIPTIO 0.007 – 0.0098 (0.178 – 0.249) 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" (0.254mm) PER SIDE ...
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... DWG # 05-08-1641) 20 0.229 – 0.244 (5.817 – 6.198) 1 0.015 0.004 0.053 – 0.068 45 (0.38 0.10) (1.351 – 1.727) 0 – 8 TYP 0.008 – 0.012 (0.203 – 0.305) LTC1433/LTC1434 0.337 – 0.344* (8.560 – 8.737) 0.058 (1.473 REF 0.150 – 0.157** (3.810 – ...
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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com Outputs L1A SSW PWRV 4.7 F** • NC PGND • BSW LTC1433 OSC 5 SGND POR 6 RUN/ 0.01 F LBO V OSENSE 8 LBI V PROG * AVX TPSD107M010R0100 ** WIMA MKS2 PART NO ...