SP6125 Datasheet, PDF (1/12 Pages) Sipex Corporation – High-Voltage, Step Down Controller in TSOT6

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SP6125
TM
High-Voltage, Step Down Controller in TSOT6
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
LX
GND _FB
6
5
4
SP6125
6 PinTSOT
1
2
3
VIN GATE VDR
DESCRIPTION
The SP6125 is a PWM controlled step down (buck) voltage mode regulator with VIN feedforward and
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
high side driver is designed to drive the gate 5V below VIN. The programmable overcurrent
protection is based on high-side MOSFET’s ON resistance sensing and allows setting the
overcurrent protection value up to 300mV threshold (measured from VIN-LX). The SP6125 is
available in a space-saving 6-pin TSOT package making it the smallest controller available capable
of operating from 24VDC supplies.
TYPICAL APPLICATION CIRCUIT
C6
0.1uF
Q1
2
FDS4685
1
Vin
Gate
Rs 2k
LX
L1, IHLP-2525CZ
8.2uH, 68mOhm, 4A
6
SP6125
3
VDR
Ds
RZ
MBRA340T3G 2K
R1
200k, 1%
GND
5
4
VFB
CZ
100pF
R2
44.2k, 1%
SHDN
D1 1N4148
High=Of f
C1
4.7uF
C4
22uF
VIN
C2
24-29 V
4.7uF
GND
VOUT
C5
22uF
3.3V
0-3A
GND
Mar22-07 RevC
SP6125: TSOT-6 PFET Buck Controller
1
 2007 Sipex Corporation