SMH4802
Preliminary Information
PIN CONFIGURATION
14-Pin SOIC
DRAIN SENSE
VGATE
EN/TS
SDA
SCL
CBSENSE
V
SS
1
2
3
4
5
6
7
14
13
12
11
10
9
8
V
DD
nc
PG#
5VREF
FS#
OV
UV
2062 14 PCon
2062 16 PCon
16-Pin SSOP
(Engineering only)
DRAIN SENSE
VGATE
EN/TS
nc
SDA
SCL
CBSENSE
V
SS
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
DD
nc
PG#
nc
5VREF
FS#
OV
UV
PIN DESCRIPTIONS
Pin No.
Type
Pin Name
DRAIN
SENSE
Pin Description
The DRAIN SENSE input monitors the voltage at the drain of the MOSFET (the
measure is with respect to V
SS
). An internal 10
µ
A source pulls the DRAIN
SENSE signal towards the 5VREF level. DRAIN SENSE must be held below
2.5V to enable the PG# output.
The VGA E output is a high side drive output, nearly equal to V
DD
, used to turn
T
on an external power MOSFET This signal supplies a constant current output
.
(100
µ
A typical) which allows easy adjustment of the MOSFET turn-on slew rate.
The ENable/T mperature Sense input is the master enable input. VGA E will be
e
T
disabled if EN/TS is less than 2.5V This pin has an internal 200k
Ω
pullup to 5V
.
.
SDA is the bidirectional serial data pin. It is configured as an open drain output.
There is an internal 50k
Ω
resistor connected to 5VREF
.
The SCL input is used to clock data into and out of the configuration registers. In
the write mode data must remain stable on SDA while SCL is HIGH. In the read
mode data is clocked out on the falling edge of SCL. There is an internal 50k
Ω
resistor connected to 5VREF
.
1
I
2
O
VGA E
T
3
4
I
I/O
EN/TS
SDA
5
I
SCL
6
I
The Circuit Breaker SENSE input is used to detect over-current conditions across
an external, low value sense resistor (R
S
) tied in series with the power MOSFET
.
CBSENSE A voltage drop of greater than 50mV across the resistor for longer than t
CBD
will
trip the circuit breaker. T disable CBSENSE connect the pin directly to V
SS
. A
o
programmable Quick-T ip sense point is also available.
r
V
SS
V
SS
is connected to the, negative side of the supply. All inputs and the 5VREF
output are referenced to V
SS
.
The UV pin is used as an under-voltage supply monitor, typically in conjunction
with an external resistor ladder. VGA E will be disabled if UV is less than 2.5V
T
.
A programmable internal hysteresis is available on the UV input, adjustable in
increments of 62.5mV A filter delay is also available on the UV input.
.
7
PWR
8
I
UV
Note: Pin numbers reflect the 14 Pin SOIC package.
2062 Pin Table A
SUMMIT MICROELECTRONICS, Inc.
2062 2.3 6/19/03
3
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
