Datasheet
© 2008 Microchip Technology Inc. DS22063B-page 15
MCP1631/HV/MCP1631V/VHV
3.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLE
3.1 Power Ground (P
GND
)
Connect power ground return pin to power ground
plane, high peak current flows through the P
GND
during
the turn on and turn off the external MOSFET devices.
3.2 Shutdown Input (SHDN)
Shutdown input logic low disables device and lowers I
Q
to minimum value, amplifier A3 (VS) remains functional
for battery voltage sense applications.
3.3 Oscillator Input (OSC
IN
)
External Oscillator Input, used to set power train
switching frequency and maximum duty cycle, V
EXT
enabled while low and disabled while high.
3.4 Oscillator Disable (OSC
DIS
)
Oscillator disable input, used to asycnronously
terminate the V
EXT
duty cycle. Commonly used to
modulate current for LED driver applications.For
minimum shutdown I
Q
, connect OSC
DIS
to SHDN.
3.5 Overvoltage Input (OV
IN
)
Overvoltage Comparator input, connect to voltage
divider, internal comparator terminates V
EXT
output in
50 ns to limit output voltage to predetermined value.
3.6 External Reference Voltage Input
(V
REF
)
External Voltage Reference input, connect fixed or
variable external reference to V
REF
, with A1 configured
as an error amplifier, the power supply output variable
(voltage or current) will follow this input.
MCP1631/MCP1631V
MCP1631HV/
MCP1631VHV
Sym Description
TSSOP/SSOP
4x4
QFN
TSSOP/SSOP
1151P
GND
Power ground return
2162SHDNShutdown input
3173OSC
IN
External oscillator input
4184OSC
DIS
Oscillator disable input
5195OV
IN
Overvoltage comparator input
6206V
REF
External voltage reference input
717A
GND
Quiet or analog ground
8,9,10 2,4,12 8,9 NC No connection
——10V
IN
High voltage input
11 3 — A
VDD_IN
Analog bias voltage input
——11A
VDD_OUT
Regulated V
DD
output
12512VS
IN
Voltage sense amplifier (A3) input
13613IS
IN
Current sense input
14714VS
OUT
Voltage sense amplifier output
15815IS
OUT
Current sense amplifier output
16 9 16 COMP Error amplifier (A1) output
17 10 17 FB Error amplifier inverting input (A1)
18 11 18 CS/V
RAMP
CS - current sense input; V
RAMP
voltage ramp input
19 13 19 P
VDD
Power V
DD
input
20 14 20 V
EXT
External driver output
— 21 — EP Exposed Thermal Pad (EP); must be connected to A
GND