SC1406 Semtech Corporation, SC1406 Datasheet - Page 2

• Manufacturer Part Number: SC1406
• Description: PORTABLE PENTIUM II & III POWER SUPPLY CONTROLLER
• Manufacturer: Semtech Corporation

PRELIMINARY - August 27, 1999
© 1999 SEMTECH CORP.
PIN DESCRIPTION:
Pin
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1
2
3
4
5
6
7
8
9
Pin Name
SSCORE
CMPREF
PWRGD
BASE25
BASE15
VCOUT
VCBYP
CLSET
CLREF
CORE
SSLR
VCIN
FB25
FB15
VID4
VID3
VID2
VID1
VID0
LBIN
DAC
GND
VCC
CMP
HYS
CO
EN
CL
2.5V Linear regulator drive.
1.5V Linear regulator drive.
Pin Function
Core comparator hysteresis settling.
Current limit setting pin.
Voltage clamp output.
Voltage clamp input.
Voltage clamp bypass pin.
VID most significant bit input.
VID input
VID input
VID input
VID least significant bit input.
2.5V Linear regulator output feedback.
1.5V Linear regulator output feedback.
Enables the IC when high. This is capable of accepting 5.0V signal level.
When the main converter output is within +10% of the VID DAC setting, this signal is
driven high to VCC level. Internal pull-down 100K.
Low battery input. This pin is used to set the minimum voltage to the converter.
When the input to this pin is less than 1.225V, the converter is held in an Under-Voltage-
Lock-Out mode regardless of the status of EN.
Linear regulators soft start. During power-up, the external soft-start capacitor (1200pF,
typ) is charged by an internal 1µA current source to set the ramp up time of the linear
regulator outputs, 1.5V and 2.5V. This ramp up time is typically 2ms, 6ms max. This is
discharged when BIASEN (internal signal) is low.
Main controller output soft start. During power-up, the external Soft-Start capacitor
(1800pF, typ) is charged by an internal 1µA current source to set the ramp up time of the
main converter output. This ramp up time is typically 3ms, 6ms max. This is discharged
when BIASEN is low. Core soft start current tolerance tracks the LDO soft start current to
within 10%.
Converter output feedback.
VID digital to analog output.
Ground
Comparator output. Main regulator controller output. Internal pull-down 100K.
Supply voltage.
Core comparator input pin.
Core comparator reference input pin.
Current limit input pin.
Current limit reference input pin.
PORTABLE PENTIUM
POWER SUPPLY CONTROLLER
652 MITCHELL ROAD
Pentium is a registered trademark of Intel Corporation
®
II & III
NEWBURY PARK CA 91320
SC1406
2