SMM764
Preliminary Information
PIN DESCRIPTIONS (Cont.)
Pin
Number
Pin
Type
Pin Name
Pin Description
SEQ_LINK (Sequence-Link™) is an open drain bi-directional pin. This pin
should be attached to other Sequence-Link devices, during linked operation.
SEQ_LINK must be pulled high through an external pull-up resistor when
multiple Sequence-Link devices are used. When the SMM764 is not used
with another Sequence-Link device, SEQ_LINK should be tied directly to
ground.
VREF (Voltage Reference) is a bi-directional analog pin. VREF is used for
Active DC Output Control and margining. VREF can be programmed to
output the internal 1.25V reference, or accept an external reference. VREF is
also used as a reference for the ADC.
FILT_CAP (Filter Capacitor) is an external capacitor input used to filter VM
X
inputs.
Leave open, do not connect. These pins must be left floating.
VM
X
(Voltage Monitor) pins are analog inputs. These pins are normally
attached to the positive converter sense line, VM
A
through VM
D.
External capacitor input used to filter the VM
X
inputs to the 10-bit ADC, CAP
A
through CAP
D
. This provides an RC filter where R = 25kΩ..
PUP
X
(Power Up Permitted) pins are programmable active high/low open
drain converter enable output, PUP
A
through PUP
D.
Output voltage used to control the output of DC/DC converters, TRIM
A
through TRIM
D.
TRIM_CAP
X
is an analog output pin used to control the output of DC/DC
converters. If the ADOC/margining functionality is not used on a channel the
associated TRIM_CAP
X
pin should be
left
floating. There are 4 TRIM_CAP
X
pins, TRIM_CAP
A
through TRIM_CAP
D
.
Power supply of the part
12VIN (12 Volt Input) is a power supply input internally regulated to either
3.6V or 5.5V.
VDD_CAP ( VDD Capacitor) is an external capacitor input used to filter the
internal supply.
13
I/O
SEQ_LINK
14
I/O
VREF
15
16,17,
18,20,
21,22,
23,25
41,36,
31,26
42,37,
32,27
43,38,
33,28
44,39,
34,29
45,40,
35,30
46
47
48
CAP
FILT_CAP
NC
No Connect
IN
CAP
OUT
OUT
VM
X
CAP
X
PUP
X
TRIM
X
CAP
TRIM_CAP
X
VDD
12VIN
VDD_CAP
PWR
PWR
CAP
Summit Microelectronics, Inc
2098 1.1 6/29/2005
6
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
