ltc3528b-2 Linear Technology Corporation, ltc3528b-2 Datasheet
ltc3528b-2
Related parts for ltc3528b-2
ltc3528b-2 Summary of contents
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... Additional features include a low shutdown current, open-drain power good output, short- circuit protection and thermal overload protection. The LTC3528B-2 is offered in an 8-lead 2mm × 3mm × 0.75mm DFN package. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ...
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... LTC3528B-2 ABSOLUTE MAXIMUM RATINGS (Note 1) V Voltage ................................................... –0. Voltage DC ............................................................ –0. Pulsed < 100ns ........................................ –0. SHDN, FB Voltage ........................................ –0. ............................................................. –0. OUT PGOOD ......................................................... –0. Operating Temperature Range (Notes 2, 5) .............................................. –40°C to 85°C Junction Temperature ........................................... 125°C Storage Temperature Range ................... –65°C to 125°C ...
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... Note 6: Failure to solder the exposed backside of the package to the PC board ground plane will result in a thermal resistance much higher than 76°C/W. Note 7: The IC is tested in a feedback loop to make the measurement. LTC3528B-2 = 1.2V 3.3V, unless otherwise noted. IN OUT ...
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... LTC3528B-2 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current and V for V = 1.8V OUT 100 90 EFFICIENCY 0 LOAD CURRENT (mA) Effi ciency vs Load Current and V for V = 3.3V OUT 100 90 EFFICIENCY 0 LOAD CURRENT (mA) Maximum Output Current ...
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... TEMPERATURE (°C) Ripple and OUT V OUT 1V/DIV 200mA/DIV SHDN PIN 35282 G19 LTC3528B 25°C unless otherwise noted) A Oscillator Frequency Change vs Temperature 5 NORMALIZED TO 25° –1 –2 –3 –4 –5 4.5 5 –50 – ...
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... LTC3528B-2 TYPICAL PERFORMANCE CHARACTERISTICS Load Step Response (3.6V to 5V) V OUT 100mV/DIV LOAD CURRENT 200mA/DIV V = 3.6V 20μs/DIV OUT C = 10μF OUT L = 2.2μH LOAD CURRENT = 100mA TO 550mA PIN FUNCTIONS SHDN (Pin 1): Logic Controlled Shutdown Input. There is an internal 4MΩ pull-down resistor on this pin. ...
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... BEST V B GATE DRIVERS AND ANTI-CROSS SHUTDOWN CONDUCTION PK COMP V REF – PK UVLO + I ZERO LOGIC CLK OSC – 10% REF TSD WAKE SGND 7 LTC3528B-2 WELL SWITCH V OUT 4 FB – ZERO COMP SLOPE COMP ERROR AMP + V REF – FB CLAMP SOFT-START EXPOSED PAD 9 35282 BD ...
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... DS(ON) nel MOSFET switch and P-channel MOSFET synchronous rectifi er, the LTC3528-2 achieves high effi ciency over a wide range of load current. The LTC3528B-2 features con- tinuous PWM operation at 2MHz. At very light loads, the LTC3528B-2 will exhibit pulse-skip operation. Operation can be best understood by referring to the Block Diagram. ...
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... L and pin) is low energy, but can cause EMI radiation. Output Disconnect The LTC3528B-2 is designed to allow true output discon- nect by eliminating body diode conduction of the internal P-channel MOSFET rectifi er. This allows for V zero volts during shutdown, drawing no current from the input source ...
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... COMPONENT SELECTION Inductor Selection The LTC3528B-2 can utilize small surface mount chip inductors due to their fast 2MHz switching frequency. Inductor values between 1.5μH and 3.3μH are suitable for most applications. Larger values of inductance will allow slightly greater output current capability by reducing the inductor ripple current ...
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... Molded chokes and some chip induc- tors usually do not have enough core area to support the peak inductor currents of 1.5A seen on the LTC3528B-2. To minimize radiated noise, use a shielded inductor. See Table 1 for suggested components and suppliers. ...
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... LTC3528B-2 PGOOD FB SHDN OFF ON GND Dual 1 Cell to 1.8V, 3V Sequenced Supply 2.2μ 0.88V TO 1.6V 475k LTC3528B-2 4.7μF PGOOD SHDN OFF ON 2.2μ 4.7μF LTC3528B-2 PGOOD SHDN 12 V OUT 1.8V 250mA 68pF 499k 10μF 1M 35282 TA02a SW V OUT1 1.8V V OUT 250mA 68pF 499k FB 10μF ...
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... LTC3528B-2 PGOOD FB SHDN OFF ON GND V OUT 3.3V 200mA 68pF 499k 10μF 287k 35282 TA04a 100 V OUT 3.3V 400mA 499k 68pF 10μF 287k 35282 TA05a LTC3528B-2 Effi ciency 100 1000 LOAD CURRENT (mA) 36282 TA04b Effi ciency ...
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... TYPICAL APPLICATIONS 2 Cell to 5V 2.2μ OUT 1.8V TO 3.2V 4.7μF LTC3528B-2 PGOOD FB SHDN OFF ON GND Li-Ion to 5V 2.2μ OUT 2.7V TO 4.2V 4.7μF LTC3528B-2 PGOOD FB SHDN OFF ON GND 14 100 OUT 5V 60 300mA 1M 50 22μF 40 316k 30 20 35282 TA06a 10 0.1 100 90 80 ...
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... LTC DWG # 05-08-1702 Rev B) 0.70 ±0.05 PACKAGE OUTLINE 0.50 BSC 2.20 ±0.05 (2 SIDES 0.115 3.00 ±0.10 TYP R = 0.05 (2 SIDES) TYP 2.00 ±0.10 (2 SIDES) 0.56 ± 0.05 (2 SIDES) 4 0.25 ± 0.05 0.75 ±0.05 0 – 0.05 BOTTOM VIEW—EXPOSED PAD LTC3528B-2 0.40 ± 0. PIN 0.20 OR 0.25 × 45° CHAMFER 1 (DDB8) DFN 0905 REV B 0.50 BSC 2.15 ±0.05 (2 SIDES) 3528b2f 15 ...
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... LTC3528B-2 RELATED PARTS PART NUMBER DESCRIPTION LTC3400/LTC3400B 600mA (I ), 1.2MHz, Synchronous Step-Up SW DC/DC Converters LTC3421 3MHz, Synchronous Step-Up DC/DC Converter SW with Output Disconnect LTC3422 1. 3MHz Synchronous Step-Up DC/DC SW Converter with Output Disconnect LTC3426 1.5MHz, Step-Up DC/DC Converter SW LTC3427 500mA (I ), 1.25MHz, Synchronous Step-Up DC/DC SW Converter with Output Disconnect ...