SMM764
Preliminary Information
Pin
Pin
Pin Name
Pin Description
Number Type
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.
13
I/O
I/O
SEQ_LINK
14
15
VREF
FILT_CAP (Filter Capacitor) is an external capacitor input used to filter VMX
CAP
NC
FILT_CAP
inputs.
16,17,
18,20,
21,22,
23,25
Leave open, do not connect. These pins must be left floating.
No Connect
41,36,
VMX (Voltage Monitor) pins are analog inputs. These pins are normally
attached to the positive converter sense line, VMA through VMD.
IN
VMX
31,26
42,37,
32,27
External capacitor input used to filter the VMX inputs to the 10-bit ADC, CAPA
CAP
OUT
OUT
CAPX
PUPX
TRIMX
through CAPD. This provides an RC filter where R = 25kΩ..
43,38,
PUPX (Power Up Permitted) pins are programmable active high/low open
33,28
drain converter enable output, PUPA through PUPD.
44,39,
34,29
Output voltage used to control the output of DC/DC converters, TRIMA
through TRIMD.
TRIM_CAPX 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_CAPX pin should be left floating. There are 4 TRIM_CAPX
pins, TRIM_CAPA through TRIM_CAPD.
45,40,
35,30
CAP
TRIM_CAPX
46
47
Power supply of the part
PWR
PWR
VDD
12VIN (12 Volt Input) is a power supply input internally regulated to either
3.6V or 5.5V.
12VIN
VDD_CAP ( VDD Capacitor) is an external capacitor input used to filter the
48
CAP
VDD_CAP
internal supply.
Summit Microelectronics, Inc
2098 1.1 6/29/2005
6
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
