Si9169

Vishay Siliconix

Document Number: 70945

S-40695—Rev. D, 19-Apr-04

www.vishay.com

1

High Frequency 1-A Synchronous Buck/Boost Converter

FEATURES

D Voltage Mode Control

D Fully Integrated MOSFET Switches

D 2.7-V to 6-V Input Voltage Range

D Programmable PWM/PSM Control

− Up to 1-A Output Current @ 3.6 V in PWM

− Up to 2-MHz Adjustable Switching Frequency in PWM

− Less than 200-mA Quiescent Current in PSM

D Integrated UVLO and POR

D Integrated Soft-Start

D Synchronization

D Shutdown Current <1 mA

DESCRIPTION

The Si9169 provides fully integrated synchronous buck or

boost converter solution for the latest one cell Lithium Ion

cellular phones. Capable of delivering up to 1 A of output

current at +3.6 V, the Si9169 provides ample power for various

baseband circuits as well as for some PAs. It combines the

2-MHz switching controller with fully integrated high-frequency

MOSFETs to deliver the smallest and most efficient converter

available today. The 2-MHz switching frequency reduces the

inductor height to new level of 2 mm and minimizes the output

capacitance requirement to less than 10 mF with peak-to-peak

output ripple as low as 10 mV. Combined with low-gate charge

high-frequency MOSFETs, the Si9169 delivers efficiency up to

95%. The programmable pulse skipping mode maintains this

high efficiency even during the standby and idle modes to

increase overall battery life and talktime. In order to extract the

last ounce of power from the battery, the Si9169 is designed

with 100% duty cycle control for buck mode. With 100% duty

cycle, the Si9169 operates like a saturated linear regulator to

deliver the highest potential output voltage for longer talktime.

Si9169 can be a drop-in replacement of Si9165 provided Pin 1

is not connected. For full 1A load condition, Pin 1 is required

to be connected to low power controller ground.

The Si9169 is available in both standard and lead (Pb)-free

TSSOP-20 pin package. In order to satisfy the stringent

ambient temperature requirements, the Si9169 is rated to

handle the industrial temperature range of −25_C to 85_C and

−40_C to 85_C.

FUNCTIONAL BLOCK DIAGRAM

MODE

SHUTDOWN

PWM/PSM

SYNC

FB

COMP

REF

PGND GND

COIL

OUTPUT

0 X 1 A

INPUT

2.7 X 6 V

Boost Configuration

Buck Configuration

SHUTDOWN

PWM/PSM

SYNC

COIL

PGND

FB

COMP

REF

PGND GND

OUTPUT

0 X 1 A

INPUT

2.7 X 6 V

MODE