LTC1434 LINER [Linear Technology], LTC1434 Datasheet
LTC1434
Related parts for LTC1434
LTC1434 Summary of contents
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... DC/DC converters. By utilizing current mode switching techniques, they provide excellent AC and = 10V) DC load and line regulation. Both devices operate at a fixed frequency with the LTC1434 phase-lockable to an external clock signal. Both devices incorporate two internal P-channel power MOSFETs with a parallel combined resistance of 0.6 (at a supply of 10V) ...
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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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... External capacitor connects be- OSC tween this pin and ground to set the operating frequency. PLL LPF (Pin 16 LTC1434): Output of the Phase Detector and Control Input of the Oscillator. Normally a series RC lowpass network is connected from this pin to ground. Tie this pin to SGND in applications which do not use the phase-locked loop ...
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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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... MOSFETs. Typically under dropout, both the power MOSFETs are on since the voltage on the I pin is greater than 0.6V. TH Frequency Synchronization A phase-locked loop (PLL) is available on the LTC1434 to allow the oscillator to be synchronized to an external U U APPLICATIONS INFORMATION The basic LTC1434 application circuit is shown in Figure 1 ...
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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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... DELAY SS By pulling the RUN/SS pin below 1.3V, the LTC1433/ LTC1434 are put in low current shutdown. This pin can be driven directly from logic as shown in Figure 8. Diode D1 in Figure 8 reduces the start delay but allows C up slowly providing the soft start function. This diode can ...
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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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... V OUT + C OUT BOLD LINES INDICATE HIGH CURRENT PATHS Figure 13. LTC1434 Layout Diagram (See Board Layout Check List the Schottky diode closely connected between the power ground and switch pin? 5. Keep the switching nodes, SSW and BSW away from sensitive small-signal nodes V ...
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... SV IN LTC1433 13 C OSC 12 POWER-ON POR RESET 680pF 5.1k V OSENSE 50pF 9 V PROG 6800pF LTC1434 Figure OUT 100 OUT 50pF OSC 0.001 0.01 0.1 LOAD CURRENT (A) V OUT C OUT 1433/34 F15 ...
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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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... LTC1433/LTC1434 U TYPICAL APPLICATIONS + 100 F* 16V V OUT – – – ( OUT(MAX) – 3 180 – 4 300 – 5 400 – 6 540 – 7 680 D1: MOTOROLA MBRS130LT3 L1: COILCRAFT DO3316 SERIES Ultralow Output Ripple 5V to – 1.25V MR Head Amplifier Supply D1: MOTOROLA MBRM5819 L1: SUMIDA CD54 SERIES L2: J ...
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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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... LTC1433/LTC1434 U TYPICAL APPLICATIO 100 F* 10V + L1B 130mA OUT(MAX 10mA OUT(MIN OUT 100 F* 10V I = 130mA OUT(MAX 5mA OUT(MIN – 5V OUT D1: MOTOROLA MBRS130LT3 L1A, L1B: MANUFACTURER COILTRONICS DALE RELATED PARTS PART NUMBER DESCRIPTION ® LT 1074/LT1076 Step-Down Switching Regulators LTC1174/LTC1174-3.3/ High Efficiency Step-Down and Inverting DC/DC Converters ...