CALIFORNIA MICRO DEVICES
1993, 1996 CMD Corp. All rights reserved.
8/96
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846
PAC 27A03
P/ACTIVE PRECISION VOLTAGE DIVIDER
NETWORK FOR LINEAR TECHNOLOGY LT1430/1017
Features
Provides a complete Pentium Pro regulator
solution when combined with a Linear Technology
LTC1430/LT1017 Power Supply Regulator Chip
Thin film tightly ratio matched resistors
using P/Active technology
SOIC and QSOP Package
SCHEMATIC CONFIGURATION
STANDARD SPECIFICATIONS
Absolute Tolerance (R)
5%
Ratio Tracking (0
o
C
T
A
70
o
C)
(Voltage per resistor <10 volts and power
per resistor <25mW)
R11/R12
0.25%
R1/R6
0.25%
R1/R7
0.5%
R1/R8
1.0%
R1/R9
2.0%
R1/(R2+R3+R4+R5)
0.25%
(R3+R4+R5)/(R1+R2)
0.5%
(R4+R5)/(R1+R2+R3)
0.5%
R5/(R1+R2+R3+R4)
0.5%
Operating Temperature Range
0
o
C to 70
o
C
Power Rating/Resistor
25mW @ 70
o
C
Storage Temperature
-65
O
C to +150
O
C
Package Power Rating
1.00W, max.
Product Description
CMDs P/Active 27A03 Precision Voltage Divider Network is designed to work with the Linear Technology LTC1430 High
Power Step-down Switching Regulator Controller. CMDs P/Active technology provides precision ratio tracking over tem-
perature range required for the proper voltage regulation in Pentium Pro-based regulator designs.
R8
R9
R1
R13
R10
R11
R12
R3
R14
R4
R5
R15
R7 R6 R2
6
7
5
4
3
13
14
15
16
2
1
11 10 9
8
12
STANDARD VALUES
Applications
Pentium Pro Power Supply Regulator
Resistor (R)
Value (Ohms)
R1
17600
R2
14219
R3
2381
R4
833
R5
12858
R6
27770
R7
55600
R8
111260
R9
222580
R10
1000
R11
33000
R12
33000
R13
47000
R14
47000
R15
47000
Refer to AP-202 Voltage Divider Application Note for
further information.
CALIFORNIA MICRO DEVICES
1993, 1996 CMD Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846
8/96
Application Diagram
PAC 27A03
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
SENS
5
7
6
SENS
VTRIM
LT 1017
LT 1430
POWER
GOOD
TO OVER
VOLTAGE
CIRCUITRY
10.7K
LT 1004
PAC 27A03
Vcc SENSE
VOLTAGE
SELECTS
MSB
LSB
74AC125
680pF
10
+5V
1.2V
REFERENCE
5.76K
+
+
+
+
ORDERING INFORMATION
Package
Ordering Part Number
Pins Style
Tubes
Tape & Reel
Part Marking
16 SOIC Narrow
PAC27A03S/T
PAC27A03S/R
PAC27A03
16 QSOP
PAC27A03Q/T
PAC27A03Q/R
PAC27A03
LT 1430/LT 1017
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