MIC2591B
Micrel
Pin Description (continued)
Pin Number
4
38
39
40
41
48
47
37
Pin Name
GPI_A0
GPI_B0
A2
A1
A0
SDA
SCL
/INT
Pin Function
General Purpose Inputs: The states of these two inputs are available by
reading the Common Status Register, Bits [4:5]. If not used, connect each
pin to GND.
SMBus Address Select Pins: Connect to ground or leave open in order to
program device SMBus base address. These inputs have internal pull-up
resistors to VSTBY[A/B].
SMBus Data: Bidirectional SMBus data line.
SMBus Clock: Input.
Interrupt Output: Open-drain, active-low. Asserted whenever a power fault
is detected if the INTMSK bit (CS Register Bit D[3]) is a logical "0". This
output is cleared by performing an "echo reset" to the appropriate fault bit(s)
in the STAT[A/B] and/or CS registers. This pin requires an external pull-up
resistor to V
STBY
.
2 Pins, IC Ground Connections: Tie directly to the system’s analog GND
plane directly at the device.
17
46
20
GND
RFILTER[A&B]
Connecting this pin to GND through a 110kΩ, 1% resistor will provide a
significant improvement in timeout duration accuracy for slow overcurrent
faults on Slot A and Slot B. If left floating (NC), overcurrent timeout duration
accuracy is determined by the specification for V
FILTER
and I
FILTER
. Please
see the “Circuit Breaker Function” text in the “Functional Description” section
for more detail.
Reserved: Make no external connections to these pins.
7
18
19
30
NC
March 2005
6
M9999-033105
MICREL [ MICREL SEMICONDUCTOR ]
