AIC1573
5-bit DAC, Synchronous PWM Power
Regulator with Simple PWM Power Regulator,
LDO And Linear Controller
Analog Integrations Corporation
4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC
www.analog.com.tw
DS-1573-01 Sep 10, 01
TEL: 886-3-5772500 FAX: 886-3-5772510
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FEATURES
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Compatible with HIP6020.
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Provides 4 Regulated Voltages for Microprocessor
Core, AGP Bus, Memory and GTL Bus Power.
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TTL Compatible 5-bit Digital-to-Analog Core Output
Voltage Selection. Range from 1.3V to 3.5V.
0.1V Steps from 2.1V to 3.5V.
0.05V Steps from 1.3V to 2.05V.
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1.0% PWM Output Voltage for VCORE.
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3% PWM Output Voltage for AGP Bus.
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3.0% Reference Voltage for Chipset and/or Ca-
che Memory and VGTL.
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Simple Voltage-Mode PWM Control with Built in
Internal Compensation Networks.
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N-Channel MOSFET Driver for PWM buck con-
verters.
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Linear Controller Drives Compatible with both N
Chanel MOSFET and NPN Bipolar Series Pass
Transistor.
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Operates from +3.3V, +5V and +12V Inputs.
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Fast Transient Response.
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Full 0% to 100% Duty Ratios.
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Adjustable Current Limit without External Sense
Resistor.
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Microprocessor Core Voltage Protection against
Upper MOSFET shorted to +5V.
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Power Good Output Voltage Monitor.
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Over-Voltage and Over-Current Fault Monitors.
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200KHz Free-Running Oscillator Programmable up
to 700KHz.
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APPLICATIONS
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Full Motherboard Power Regulation for Computers.
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DESCRIPTION
The AIC1573 combines two PWM voltage mode
controllers and two linear controllers as well as the
monitoring and protection functions in this chip. One
PWM controller regulates the microprocessor core
voltage with a synchronous rectified buck converter.
The second PWM controller provides AGP bus 1.5V
or 3.3V power with a standard buck converter. Two
linear controllers regulate power for the 1.5V GTL
bus and 1.8V power for the chip set core voltage
and/or cache memory circuits.
An integrated 5 bit D/A converter that adjusts the
microprocessor core voltage from 2.1V to 3.5V in
0.1V increments and from 1.3V to 2.05V in 0.05V
increments. The second PWM controller for AGP
bus power is selectable by means of SELECT pin
status for 1.5V or 3.3V with 3% accuracy. Two linear
controllers drive with external N-channel MOSFETs
to provide 1.5V3% and fixed output voltage
1.8V3%.
This chip monitors all the output voltages. Power
Good signal is issued when the core voltage is
within 10% of the DAC setting and the other levels
are above their under-voltage levels. Over-voltage
protection for the core output uses the lower N-
channel MOSFET to prevent output voltage above
116% of the DAC setting.
The PWM over-current function monitors the output
current by using the voltage drop across the upper
MOSFET's R
DS(ON)
,
eliminating the need for a cur-
rent sensing resistor
.
AIC1573
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ORDERING INFORMATION
ORDER NUMBER
PIN CONFIGURATION
AIC1573-CX
AIC157 3CS
(SO28)
PACKAGING TYPE
S: SMALL OUTLINE
1
3
4
2
5
7
6
8
9
10
VID 1
PHASE2
VID 4
VID 3
UGATE2
VID 2
VSEN2
VID0
OCSET2
PGOOD
11
12
SS
SELECT
PHASE1
V C C
UGATE1
OCSET1
LGATE1
PGND
20
19
VSEN1
VSEN3
FB1
NC
28
26
27
25
24
23
21
22
18
17 GND
DRIVE3
13
14
VSEN4
FAULT/RT
16
15 DRIVE4
VAUX
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ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC .................. ... ... ... ... ........ ... ... ... ............ ..... ... ..................... +15V
PGOOD, FAULT and GATE Voltage ........ ... ... ........ ... ... ..... .... GND -0.3V to V
CC
+0.3V
Input, Output , or I/O Voltage ......... ...... ... ... ... ... ... ... ... ... ..... ... ............ GND -0.3V to 7V
Recommended Operating Conditions
Supply Voltage; VCC... ... ..... ... ... ... .............. ................... +12V10%
Ambient Temperature Range ... ... ..... ... ..... ... ... ................. 0
C~70
C
Junction Temperature Range ... ... ....... .... ... ... .................. 0
C~125
C
Thermal Information
Thermal Resistance,
JA
SOIC package ... ... ... ... ... ... ... ... ... ... ... ... ... ..... ..... .............. 70
C/W
SOIC package (with 3in
2
of copper) ... ...... ..... ... .......... ......... 50
C/W
Maximum Junction Temperature (Plastic Package) ... ... ... ... ... ... ... ..... ... ...... 150
C
Maximum Storage Temperature Range ... ... ... ... ... ... ... ... ..... ... ... .... -65
C ~ 150
C
Maximum Lead Temperature (Soldering 10 sec)
... ... ... ... ... ... ... ... ... ... ..... ... 300
C
AIC1573
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ELECTRICAL CHARACTERISTICS
(Vcc=12V, TA=25
C, Unless otherwise specified)
PARAMETER
TEST CONDITIONS
SYMBOL
MIN.
TYP.
MAX.
UNIT
VCC SUPPLY CURRENT
Supply Current
UGATE1, LGATE1, UGATE2,
DRIVE3 and DRIVE4 open
I
CC
3
mA
POWER ON RESET
Rising VCC Threshold
VOCSET=4.5V
V
CCTHR
10.4
V
Falling VCC Threshold
VOCSET=4.5V
V
CCTHF
8.2
V
Rising VAUX Threshold
VAUX
THR
2.5
V
VAUX Threshold Hysteresis
VAUX
HYS
500
mV
Rising VOCSET1 Threshold
V
OCSETH
1.26
V
OSCILLATOR
Free Running Frequency
RT=Open
F
170
200
230
KHz
Total Variation
6k
<RT to GND<200k
-15
+15
%
Ramp. Amplitude
RT=open
V
OSC
1.5
VP-P
DAC AND STANDARD BUCK REGULATOR REFERENCE
DAC (VID0~VID4) Input Low
Voltage
V
IDL
0.8
V
DAC (VID0~VID4) Input High
Voltage
V
IDH
2.0
V
DACOUT Voltage Accuracy
V
DAC
=1.8V~3.5V
-1.0
+1.0
%
PWM2 Reference Voltage
Select < 0.8V
1.5
V
PWM2 Reference Voltage
Select > 2.0V
3.3
V
PWM2 Reference Voltage
Tolerance
3
%
1.5V AND 1.8V LINEAR REGULATORS ( OUT3, OUT4)
Regulation
3
%
VSEN3 Regulation Voltage
V
REG3
1.5
V
VSEN4 Regulation Voltage
V
REG4
1.8
V
Under-Voltage Level
( V
SEN
/V
REG
)
V
SEN
Rising
V
SENUV
75
%
Under-Voltage Hysteresis
(V
SEN
/V
REG
)
V
SEN
Falling
5
%
Output Drive Current ( All
Linears )
V
AUX
-V
DRIVE
> 0.6V
20
30
mA
AIC1573
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ELECTRICAL CHARACTERISTICS
(Continued)
PARAMETER
TEST CONDITIONS
SYMBOL MIN.
TYP.
MAX.
UNIT
SYNCHRONOUS PWM CONTROLLER AMPLIFIER
DC Gain
(G.B.D.)
80
dB
Gain-Bandwidth Product
(G.B.D.)
G
BWP
13
MHz
Slew Rate
(G.B.D.) note 1.
S
R
6
V/
s
PWM CONTROLLER GATE DRIVERS
U
GATE1,2
Upper Drive Source
V
CC
=12V, V
U
GATE
= 6V
I
UGH
0.9
A
U
GATE1,2
Upper Drive Sink
V
UGATE
=1V
R
UGL
2.8
3.5
Lower Drive Source
V
CC
=12V, V
LGATE
=1V
I
LGH
1
A
Lower Drive Sink
V
LGATE
=1V
R
LGL
2.2
3.0
PROTECTION
VSEN1 Over-Voltage
( V
SEN1
/DACOUT)
V
SEN1
Rising
OVP
116
120
%
FAULT Sourcing Current
V
CC
-
V
FAULT/RT
=2.0V
I
OVP
20
mA
OCSET1,2 Current Source
V
OCSET
=4.5VDC
I
OCSET
170
200
230
A
Soft-Start Current
I
SS
25
A
POWER GOOD
V
SEN1
Upper Threshold
( V
SEN1
/DACOUT )
V
SEN1
Rising
108
111
%
V
SEN1
Under-Voltage
( VSEN1/DACOUT )
V
SEN1
Falling
92
95
%
V
SEN1
Hysteresis
(VSEN1/DACOUT)
Upper and Lower Threshold
2
%
P
GOOD
Voltage Low
I
PGOOD
=-4mA
V
PGOOD
0.4
0.8
V
Note 1. Without internal compensation network, the gain bandwidth product is 13MHz. Being associated with
internal compensation networks, the Bode Plot is shown in Fig. 3, "Internal Compensation Gain of
PWM Error Amplifier".
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