SMM766
Preliminary Information
PIN DESCRIPTIONS
Pin
Number
1
2
3
Pin
Type
DATA
CLK
IN
Pin Name
SDA
SCL
A2
Pin Description
SDA (Serial Data) is an open drain bi-directional pin used as the I
2
C data
line.
SCL (Serial Clock) is an open drain input pin used as the I
2
C Clock line.
The A2 (Address bit 2) pin is biased either to VDD_CAP or GND. When
communicating with the SMM766 over the 2-wire I
2
C bus, A2 provides a
mechanism for assigning a unique bus address.
MR# (Manual Reset) is an active low input. When asserted the RST# output
will become active. When de-asserted the RST# output will go inactive
immediately after a reset timeout period (t
RTO
) if there are no RST# trigger
sources active. This timeout period makes it suitable to use as a pushbutton
for manual reset purposes.
PWR_ON (Power On) is an open drain bi-directional pin. On the rising edge
of PWR_ON the part will sequence the supplies on, during the falling edge
the part will sequence the supplies off. This pin must be tied high through an
external pull-up resistor.
Note: The SMM766 does not monitor for faults during power-on/off
sequencing.
FS# (Force Shutdown) is an open drain active low bi-directional pin. FS# is
used to immediately turn off all converter enable signals (PUP outputs) when
a fault is detected. Whenever FS# is asserted PWR_ON will automatically be
pulled low as well. This pin must be tied high through an external pull-up
resistor.
The FAULT# pin is an active low open drain output. Active when a
programmed fault condition exists on AIN1, AIN2, or the internal temperature
sensor. When used, FAULT# should be pulled high through an external pull-
up resister.
HEALTHY is an active high open drain output. Active when all programmed
power supply inputs and monitored inputs are within OV and UV limits and
ADOC has begun. When used, HEALTHY should be pulled high through an
external pull-up resistor.
RST# (Reset) is an active low open drain output pin. Active when a
programmed fault condition exists on any power supply inputs or monitored
inputs, when MR# is active, or when ADOC is not ready. RST# has a
programmable timeout period with options for 0.64ms, 25ms, 100ms and
200ms. When used, RST# should be pulled high through an external pull-up
resistor.
AIN1 (Analog Input 1) is a general-purpose monitored analog input.
AIN2 (Analog Input 2) is a general-purpose monitored analog input.
Ground.
4
IN
MR#
5
I/O
PWR_ON
6
I/O
FS#
7
OUT
FAULT#
8
OUT
HEALTHY
9
OUT
RST#
10
11
12
IN
IN
GND
AIN1
AIN2
GND
Summit Microelectronics, Inc
2086 2.1 12/13/2005
5
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
