SMM665B
Preliminary Information
PIN DESCRIPTIONS
Pin
Pin
Pin Name
Pin Description
Number Type
1
I2C Bi-directional data line
I2C Clock line
DATA SDA
2
CLK
SCL
The address pin is biased either to VDD_CAP or GND.
When
3
IN
A2
communicating with the SMM665B over the 2-wire bus A2 provides a
mechanism for assigning a unique bus address.
Programmable active high/low input. When asserted the RST output will be
go active. When de-asserted the RST output will go inactive immediately
after a reset timeout period (tPRTO) if there are no RST trigger sources active.
This timeout period makes it suitable to use a pushbutton for manual reset.
Programmable active high/low input signals the start of the power
sequencing. When asserted the part will sequence the supplies on and
when de-asserted the part will sequence the supplies off.
Note: The SMM665B does not monitor for faults during sequencing. The
PWR_ON/OFF pin is overridden by the I2C power on/off command. To get
the pin to work again requires the part be given an I2C 'Clear' command (see
page 16, “RESTART OF POWER-ON CASCADE SEQUENCING”).
4
5
IN
IN
MR
PWR_ON/OFF
Programmable active high/low input. Force shutdown is used to immediately
6
7
IN
FS
turn off all converter enable signals (PUP outputs) when a fault is detected.
Programmable active high/low open drain Fault output. Active when a
programmed fault condition exists on AIN1, AIN2, or the internal temperature
sensor.
OUT
FAULT
Programmable active high/low open drain Healthy output. Active when all
programmed power supply inputs and monitored inputs are within OV and
UV limits.
Programmable active high/low open drain Reset output. Active when a
programmed fault condition exists on any power supply inputs or monitored
inputs or when MR is active. RST has a programmable timeout period with
options for 0.64ms, 25ms, 100ms and 200ms.
8
9
OUT
OUT
HEALTHY
RST
10
11
12
General purpose monitored analog input
General purpose monitored analog input
Ground
IN
AIN1
AIN2
GND
IN
GND
Voltage reference input used for A/D conversion where:
(4XVREF_ADC) = Full Scale (FS) for VMA-F and VDD
(12XVREF_ADC) = FS for 12VIN
13
IN
VREF_ADC
(2XVREF_ADC) = FS for AIN1 and AIN2.
VREF_ADC can be connected to VREF_CNTL in most applications.
Summit Microelectronics, Inc
2089 1.1 10/20/04
4
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
