LTC1435ACS#TR Linear Technology, LTC1435ACS#TR Datasheet
LTC1435ACS#TR
Specifications of LTC1435ACS#TR
Available stocks
Related parts for LTC1435ACS#TR
LTC1435ACS#TR Summary of contents
Page 1
... The operating cur- rent level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 30V (36V maximum). , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation ...
Page 2
LTC1435A ABSOLUTE MAXIMUM Input Supply Voltage (V )......................... 36V to – 0.3V IN Topside Driver Supply Voltage (BOOST)....42V to – 0.3V Switch Voltage (SW)............................. V EXTV Voltage ........................................ 10V to – 0. – SENSE , ...
Page 3
ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER Oscillator f Oscillator Frequency OSC The denotes specifications which apply over the full operating temperature range. LTC1435ACG/LTC1435ACS LTC1435AIG/LTC1435AIS: – Note calculated ...
Page 4
LTC1435A W U TYPICAL PERFORMANCE CHARACTERISTICS Input Supply and Shutdown Current vs Input Voltage 2.5 2 OUT 1.5 EXTV = V CC OUT V = 3.3V 1.0 OUT EXTV = OPEN CC 0.5 SHUTDOWN ...
Page 5
W U TYPICAL PERFORMANCE CHARACTERISTICS Burst Mode Operation V OUT 20mV/DIV V ITH 200mV/DIV I = 50mA LOAD PIN FUNCTIONS C (Pin 1): External capacitor C OSC ground sets the operating frequency. RUN/SS (Pin 2): Combination of ...
Page 6
LTC1435A U U FUNCTIONAL DIAGRA 1 OSC + OV – 1.28V V OSENSE V FB – 1.19V 180k m SHUTDOWN RUN 30k SOFT START RUN/SS 3 ...
Page 7
U OPERATION (Refer to Functional Diagram) on and periodically forces a brief off period to allow C recharge. The main control loop is shut down by pulling the RUN/SS pin low. Releasing RUN/SS allows an internal 3 A current source ...
Page 8
LTC1435A U U APPLICATIONS INFORMATION The value calculated from the desired operating OSC frequency: 4 1.37( OSC Frequency (kHz) A graph for selecting C vs frequency is given in Figure OSC 2. ...
Page 9
U U APPLICATIONS INFORMATION a fixed inductor value, but it is very dependent on induc- tance selected. As inductance increases, core losses go down. Unfortunately, increased inductance requires more turns of wire and therefore copper losses will increase. Ferrite designs ...
Page 10
LTC1435A U U APPLICATIONS INFORMATION C and C Selection IN OUT In continuous mode, the source current of the top N-channel MOSFET is a square wave of duty cycle prevent large voltage transients, a low ESR ...
Page 11
U U APPLICATIONS INFORMATION control power to be derived from the output during normal operation (4.8V < V < 9V) and from the internal regu- OUT lator when the output is out of regulation (start-up, short circuit). Do not apply ...
Page 12
LTC1435A APPLICATIONS INFORMATION The external resistive divider is connected to the output as shown in Figure 5 allowing remote voltage sensing. 1.19V V OSENSE 100pF LTC1435A SGND 1435A F05 Figure 5. Setting the LTC1435A Output Voltage Run/ ...
Page 13
U U APPLICATIONS INFORMATION on and off again determined by internal timing delays and the gate charge required to turn on the top MOSFET. Low duty cycle applications may approach this minimum on-time limit. If the duty cycle ...
Page 14
LTC1435A U U APPLICATIONS INFORMATION By powering EXTV from an output-derived source, the CC additional V current resulting from the driver and IN control currents will be scaled by a factor of Duty Cycle/Efficiency. For example 20V to ...
Page 15
U U APPLICATIONS INFORMATION conduct during double battery operation, but must still clamp the input voltage below breakdown of the converter. Although the LTC1435A has a maximum input voltage of 36V, most applications will be limited to 30V by the ...
Page 16
LTC1435A U U APPLICATIONS INFORMATION 4. Does the (+) plate of C connect to the drain of the IN topside MOSFET(s) as closely as possible? This capaci- tor provides the AC current to the MOSFET(s the INTV decoupling ...
Page 17
U TYPICAL APPLICATIONS C OSC 68pF 1 C OSC RUN/ 10k 470pF 51pF 4 SFB LTC1435A 5 SGND 100pF 6 V OSENSE 7 – SENSE 1000pF ...
Page 18
LTC1435A U TYPICAL APPLICATIONS Constant-Current/Constant-Voltage High Efficiency Battery Charger C1* C2 1.5M 35V 35V E3 GND E3 SHDN C12 C13 R5 0.1 F 0.033 F 1k C14 1000pF C15 LT1620 ...
Page 19
... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
Page 20
... High Efficiency 5V to 3.3V Conversion 15A Full-Featured Single Controller Full-Featured Dual Controllers 1.3A, Li-Ion, NiCd, NiMH, Pb-Acid Charger 5V Standby in Shutdown 5V Standby in Shutdown Creates a Programmable 1. Supply for Intel ® Mobile Pentium II Processor When Used with the LTC1435A 1435af LT/GP 0798 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 ...