ISL6523A Intersil Corporation, ISL6523A Datasheet

no-image

ISL6523A

Manufacturer Part Number
ISL6523A
Description
VRM8.5 Dual PWM and Dual Linear Power System Controller
Manufacturer
Intersil Corporation
Datasheet
VRM8.5 Dual PWM and Dual Linear Power
System Controller
The ISL6523A provides the power control and protection for
four output voltages in high-performance microprocessor
and computer applications. The IC integrates two PWM
controllers and two linear controllers, as well as the
monitoring and protection functions into a 28-pin SOIC
package. One PWM controller regulates the microprocessor
core voltage with a synchronous-rectified buck converter.
The second PWM controller supplies the computer system’s
AGTL+ 1.2V bus power with a standard buck converter. The
linear controllers regulate power for the 1.5V AGP bus and
the 1.8V power for the chipset core voltage and/or cache
memory circuits.
The ISL6523A includes an Intel VRM8.5 compatible, TTL
5-input digital-to-analog converter (DAC) that adjusts the
microprocessor core-targeted PWM output voltage from
1.050V to 1.825V in 25mV steps. The precision reference
and voltage-mode control provide 1% static regulation. The
second PWM controller’s output provides a voltage level of
1.2V with 3% accuracy. The linear regulators use external
N-channel MOSFETs or bipolar NPN pass transistors to
provide fixed output voltages of 1.5V 3% (V
The ISL6523A monitors all the output voltages. A delayed-
rising VTT (standard buck output) Power Good signal is
issued before the core PWM starts to ramp up. Another
system Power Good signal is issued when the core is within
their under- voltage levels. Additional built-in overvoltage
protection for the core output uses the lower MOSFET to
prevent output voltages above 115% of the DAC setting. The
PWM controllers’ overcurrent function monitors the output
current by using the voltage drop across the upper
MOSFET’s r
sensing resistor.
Ordering Information
ISL6523ACB
ISL6523EVAL1
3% (V
10% of the DAC setting and all other outputs are above
PART NUMBER
OUT4
DS(ON)
).
Evaluation Board
, eliminating the need for a current
RANGE (
TEMP.
0 to 70
TM
o
C)
1
28 Ld SOIC
Data Sheet
PACKAGE
OUT3
) and 1.8V
M28.3
PKG.
NO.
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
Features
• Provides 4 Regulated Voltages
• Drives N-Channel MOSFETs
• Linear Regulator Drives Compatible with both MOSFET
• Simple Single-Loop Control Designs
• Fast PWM Converter Transient Response
• Excellent Output Voltage Regulation
• VRM8.5 TTL-Compatible 5-Bit DAC Microprocessor Core
• Power-Good Output Voltage Monitors
• Overcurrent Fault Monitors
• Small Converter Size
Applications
• Motherboard Power Regulation for Computers
Pinout
- Microprocessor Core, AGTL+ Bus, AGP Bus Power,
and Bipolar Series Pass Transistors
- Voltage-Mode PWM Control
- High-Bandwidth Error Amplifiers
- Full 0% to 100% Duty Ratios
- Core PWM Output . . . . . . . . . . 1% Over Temperature
- All Other Outputs
Output Voltage Selection
- Wide Range . . . . . . . . . . . . . . . . . . . . 1.050V to 1.825V
- Separate delayed VTT Power Good
- Switching Regulators Do Not Require Extra Current
- Constant Frequency Operation
- 200kHz Internal Oscillator
and North/South Bridge Core
Sensing Elements, Use MOSFET’s r
February 2002
UGATE2
PHASE2
OCSET2
PGOOD
VTTPG
VSEN2
VSEN4
VID25
SS24
SS13
VID3
VID2
VID1
VID0
|
Copyright © Intersil Americas Inc. 2002. All Rights Reserved
Intersil (and design) is a trademark of Intersil Americas Inc.
10
11
12
13
14
1
2
3
4
5
6
7
8
9
ISL6523A (SOIC)
TOP VIEW
3% Over Temperature
28
27
26
25
24
23
22
21
20
19
18
17
16
15
ISL6523A
DS(ON)
VCC
UGATE1
PHASE1
LGATE1
PGND
OCSET1
VSEN1
FB1
COMP1
VSEN3
DRIVE3
GND
VAUX
DRIVE4
FN9063

Related parts for ISL6523A

ISL6523A Summary of contents

Page 1

... TM Data Sheet VRM8.5 Dual PWM and Dual Linear Power System Controller The ISL6523A provides the power control and protection for four output voltages in high-performance microprocessor and computer applications. The IC integrates two PWM controllers and two linear controllers, as well as the monitoring and protection functions into a 28-pin SOIC package ...

Page 2

VSEN3 VAUX 1.5V EA3 - DRIVE3 + x0.75 x0.75 + DRIVE4 - EA4 + VSEN4 1.8V - VCC DRIVE2 UGATE2 + - PHASE2 INHIBIT PWM GATE COMP2 CONTROL - + PWM2 VSEN2 - + EA2 UV2 - + x0.90 + ...

Page 3

... LINEAR CONTROLLER CONTROLLER FIGURE 2. SIMPLIFIED POWER SYSTEM DIAGRAM VCC OCSET2 OCSET1 PGOOD UGATE2 PHASE2 UGATE1 PHASE1 LGATE1 VSEN2 PGND VSEN1 VTTPG FB1 ISL6523A VAUX COMP1 DRIVE3 VSEN3 VID3 VID2 VID1 VID0 DRIVE4 VID25 VSEN4 SS13 SS24 C SS24 GND FIGURE 3. TYPICAL APPLICATION ...

Page 4

... SYNCHRONOUS PWM CONTROLLER ERROR AMPLIFIER DC Gain Gain-Bandwidth Product Slew Rate PWM CONTROLLERS GATE DRIVERS UGATE1,2 Source UGATE1,2 Sink 4 ISL6523A Thermal Information Thermal Resistance (Typical, Note 1) SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 0.3V Maximum Junction Temperature (Plastic Package 150 CC Maximum Storage Temperature Range . . . . . . . . . . -65 Maximum Lead Temperature (Soldering 10s .300 ...

Page 5

... MOSFETs controlled by the IC. The voltage at this pin is monitored for Power-On Reset (POR) purposes. GND (Pin 17) Signal ground for the IC. All voltage levels are measured with respect to this pin. 5 ISL6523A SYMBOL TEST CONDITIONS I VCC = 12V LGATE ...

Page 6

... Connect this pin to the output of the linear 1.8V regulator. This pin is monitored for undervoltage events. Description Operation The ISL6523A monitors and precisely controls 4 output voltage levels (Refer to Figures designed for microprocessor computer applications with 3.3V, 5V, and 12V bias input from an ATX power supply. The IC has 2 PWM and two linear controllers ...

Page 7

... VTTPG pin to go high. The oscillator’s triangular wave form is compared to the clamped error amplifier output voltage. 7 ISL6523A As the SS13 pin voltage increases, the pulse-width on the PHASE1 pin increases, bringing the OUT1 output within regulation limits. Similarly, the SS13 voltage clamps the reference voltage for OUT3, enabling a controlled output voltage ramp-up ...

Page 8

... VSEN pins for under-voltage. Should excessive currents cause VSEN3 or VSEN4 to fall below the linear under-voltage threshold, the respective UV signals set the 8 ISL6523A OC latch or the FAULT latch, providing respective C capacitors are fully charged. Blanking the UV signals during the C charge interval allows the linear outputs to build above SS the under-voltage threshold during normal operation ...

Page 9

... ISL6523A TABLE 1. OUT1 OUTPUT VOLTAGE PROGRAM (Continued +5V IN VID3 OCSET SET PHASE – V PHASE ...

Page 10

... There are two sets of critical components in a DC-DC converter using an ISL6523A controller. The switching power components are the most critical because they switch large amounts of energy, and as such, they tend to generate equally large amounts of noise ...

Page 11

... The compensation network consists of the error amplifier (internal to the ISL6523A) and the impedance networks Z and Z . The goal of the compensation network is to provide a FB closed loop transfer function with high 0dB crossing frequency (f ) and adequate phase margin. Phase margin is the ...

Page 12

... Given a sufficiently fast control loop design, the ISL6523A will provide either 0% or 100% duty cycle in response to a load transient. The response time is the time interval required to slew the inductor current from an initial current value to the post-transient current level ...

Page 13

... MOSFET’s body diode or the output capacitances associated with either MOSFET. The gate charge losses are dissipated by the controller IC (ISL6523A) and do not contribute to the MOSFETs’ heat rise. Ensure that both MOSFETs are within their maximum junction temperature at high ambient temperature by calculating the temperature rise according to package thermal resistance specifications ...

Page 14

... SCH V IN Linear Controllers Transistor Selection The ISL6523A linear controllers are compatible with both NPN bipolar as well as N-channel MOSFET transistors. The main criteria for selection of pass transistors for the linear 14 ISL6523A regulators is package selection for efficient removal of heat. The power dissipated in a linear regulator is ...

Page 15

... ISL6523A DC-DC Converter Application Circuit Figure 13 shows an application circuit of a power supply for a microprocessor computer system. The power supply provides the microprocessor core voltage (V bus voltage (V ), the GTL bus voltage (V OUT2 +5V +12V +3.3V GND GND GND R2 2.2k Q3 HUF76121 L2 V (VTT) OUT2 2.0 H +1. CR1 ...

Page 16

... Irvine Center Drive 2401 Palm Bay Rd. Suite 100 Palm Bay, FL 32905 Irvine, CA 92618 TEL: (321) 724-7000 TEL: (949) 341-7000 FAX: (321) 724-7946 FAX: (949) 341-7123 16 ISL6523A M28.3 (JEDEC MS-013-AE ISSUE C) 28 LEAD WIDE BODY SMALL OUTLINE PLASTIC PACKAGE SYMBOL A A1 ...

Related keywords