pip250m NXP Semiconductors, pip250m Datasheet - Page 4

• Manufacturer Part Number: pip250m
• Description: Pip250m Integrated Buck Converter
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7. Functional description
9397 750 10904
Product data
7.1.1 Output stage supply (V
7.1.2 Output voltage (VO)
7.1.3 Control circuit supply (V
7.1.4 Bootstrap capacitor connection (CB)
7.1.5 Voltage feedback pin (FB)
7.1.6 Current limit set and enable input (OCSET/ENABLE)
7.1.7 Sense connection for current limit (PHASE)
7.1 Pin functions
[1]
[2]
The power output stage of the PIP250M consists of two N-channel, power MOSFETs
and a Schottky diode configured as a synchronous buck converter. The drain of the
upper MOSFET is connected to the positive conversion supply (V
source of the lower MOSFET is connected to power ground (V
diode is connected between the source and drain of the lower MOSFET.
VO is the switched node of the power MOSFET output stage. This node is connected
internally to the source of the upper MOSFET and the drain of the lower MOSFET.
V
control voltages are measured with respect to V
The upper MOSFET driver stage is powered from the CB pin.
The FB pin is connected to the inverting input of the error amplifier, and to the inputs
of the overvoltage and undervoltage comparators.
The overcurrent threshold is set by an external resistor between V
OCSET/ENABLE. The PIP250M can be shut down by pulling this pin LOW.
The PHASE input is normally connected externally to the power output stage
switched node (VO). The voltage on the PHASE input is compared with the voltage
on the OCSET/ENABLE input during the interval when the upper MOSFET is on. The
overcurrent trip operates if the voltage on the PHASE input is lower than the voltage
on the OCSET/ENABLE input.
DDC
PAD1, PAD2 and PAD3 are electrical connections and must be soldered to the printed circuit board
All n.c. pins should be connected to V
is the positive supply to the control circuit. V
Rev. 02 — 21 February 2003
DDO
DDC
, V
, V
SSO
SSC
SSC
)
)
.
SSC
SSC
.
is the control circuit ground. All
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
Integrated buck converter
SSO
DDO
). The Schottky
DDO
PIP250M
), and the
and
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