Mar22-07 RevC

SP6125: TSOT-6 PFET Buck Controller

 2007 Sipex Corporation

1

FEATURES

Wide 4.5V – 29V Input Voltage Range

Internal Compensation

Built-in High Current PMOS Driver

Adjustable Overcurrent Protection

Internal soft-start

300kHz Constant Frequency Operation

0.6V Reference Voltage

1% output setpoint accuracy

Lead Free, RoHS Compliant Package:

Small 6 pin TSOT

DESCRIPTION

internal Type-II compensation. It operates from 4.5V to 29V, making is suitable for 5V, 12V, and 24V

applications. By using a PMOS driver, this device is capable of operating at 100% duty cycle. The

protection is based on high-side MOSFET’s ON resistance sensing and allows setting the

available in a space-saving 6-pin TSOT package making it the smallest controller available capable

of operating from 24VDC supplies.

TYPICAL APPLICATION CIRCUIT

High=Of f

L1, IHLP-2525CZ

8.2uH, 68mOhm, 4A

C4

22uF

Ds

MBRA340T3G

R1

200k, 1%

RZ

2K

R2

44.2k, 1%

Q1

FDS4685

CZ

100pF

C6

0.1uF

C1

4.7uF

Rs 2k

D1 1N4148

24-29 V

SHDN

VIN

VOUT

GND

GND

VFB

Vin

LX

GND

VDR

Gate

SP6125

3.3V

0-3A

3

1

4

5

2

6

C5

22uF

C2

4.7uF

SP6125

6

5

4

1

2

3

SP6125

6 PinTSOT

GND

LX

GATE

FB

VDR

Solved by

TM

High-Voltage, Step Down Controller in TSOT6