ADM1041ARQ ,Secondary-Side Controller w/Current Share and HousekeepingSpecifications.... 6 Pulse ... 27 Absolute Maximum Ratings.... 13 ACSENSE 27 ESD Caution........ 13 ..
ADM1041ARQ-REEL , Secondary-Side Controller with Current Share and Housekeeping
ADM1051AJR ,Precision Dual Voltage Regulator ControllersFEATURESThe ADM1051/ADM1051A are dual, precision, voltage regula-Two Independent Controllers on One ..
ADM1051AJR-REEL7 ,Precision Dual Voltage Regulator ControllersSPECIFICATIONS channels, unless otherwise noted. See Test Circuit.)Parameter Min Typ Max Unit Test ..
ADM1051AJRZ ,Precision Dual Voltage Regulator ControllersFEATURESThe ADM1051/ADM1051A are dual, precision, voltage regula-Two Independent Controllers on One ..
ADM1051JR ,Precision Dual Voltage Regulator ControllersSpecifications subject to change without notice.–2– REV. 0ADM1051/ADM1051AABSOLUTE MAXIMUM RATINGS* ..
AH183-WLA , LOW POWER HALL EFFECT SWITCH
AH183-WLA , LOW POWER HALL EFFECT SWITCH
AH1883-ZG-7 , MICROPOWER, ULTRA-SENSITIVE HALL EFFECT SWITCH
AH1884-ZG-7 , MICROPOWER, ULTRA-SENSITIVE HALL EFFECT
AH1885-ZG-7 , MICROPOWER, ULTRA-SENSITIVE HALL EFFECT SWITCH
AH1886-ZG-7 , MICROPOWER, ULTRA-SENSITIVE HALL EFFECT
ADM1041ARQ
Secondary-Side Controller w/Current Share and Housekeeping
Secondary-Side Controller with
Current Share and Housekeeping
Rev. A
PRODUCT FEATURES
Digital calibration via internal EEPROM
Supports SSI specification
Comprehensive fault detection
Reduced component count on secondary side
Standalone or microcontroller control
SECONDARY-SIDE FEATURES
Generates error signal for primary-side PWM
Output voltage adjustment and margining
Current sharing
Current limit adjustment
OrFET control
Programmable soft-start slew rate
Standalone or microcontroller operation
Differential load voltage sense
AC mains undervoltage detection (ac sense)
Overvoltage protection
INTERFACE AND INTERNAL FEATURES
SMBus interface (I2C compatible)
Low-drift precision 2.5 V reference
Voltage error amplifier
Differential current sense
Sense resistor or current transformer option
Overvoltage protection
Undervoltage protection
Overcurrent protection
Overtemperature protection
Start-up undervoltage blanking
Programmable digital debounce and delays
352-byte EEPROM available for field data
160-byte EEPROM for calibration
Ground continuity monitoring
APPLICATIONS
Network servers
Web servers
Power supply control
VDD
ISOLATION BARRIERFigure 1. Typical Application Circuit
TABLE OF CONTENTS Specifications.....................................................................................6
Absolute Maximum Ratings..........................................................13
ESD Caution................................................................................13
Pin Configuration and Function Descriptions...........................14
Terminology....................................................................................17
Theory of Operation......................................................................19
Power Management....................................................................19
Gain Trimming and Configuration.........................................19
Differential Remote Sense Amplifier............................................20
Set Load Voltage..........................................................................20
Load Overvoltage (OV).............................................................20
Local Voltage Sense....................................................................20
Local OverVoltage Protection (OVP)......................................20
Local UnderVoltage Protection (UVP)...................................20
False UV Clamp..........................................................................20
Voltage Error Amplifier.............................................................21
Main Voltage Reference.............................................................21
Current Sense Amplifier............................................................21
Current Sensing..........................................................................22
Current Transformer Input.......................................................22
Current Sense Calibration.........................................................22
Current Limit Error Amplifier..................................................22
Overcurrent Protection.............................................................22
Current Share..................................................................................24
Current Share Offset..................................................................24
ISHARE Drive Amplifier.................................................................24
Differential Sense Amplifier......................................................24
ISHARE Error Amplifier.................................................................24
ISHARE Clamp.................................................................................24
Share_ok Detector......................................................................24
Pulse.............................................................................................27
ACSENSE..........................................................................................27
OrFET Gate Drive......................................................................28
Oscillator and Timing Generators...............................................30
Logic I/O and Monitor Pins......................................................30
SMBus Serial Port.......................................................................33
Microprocessor Support............................................................33
Broadcasting................................................................................34
SMBus Serial Interface...............................................................34
General SMBus Timing.............................................................34
SMBus Protocols for RAM and EEPROM..............................36
SMBus Read Operations...........................................................38
SMBus Alert Response Address (ARA)...................................39
Support for SMBus 1.1...............................................................39
Layout Considerations...............................................................39
Power-Up Auto-Configuration................................................39
Extended SMBus Addressing....................................................40
Backdoor Access.........................................................................40
Register Listing...............................................................................41
Detailed Register Descriptions.....................................................42
Manufacturing Data...................................................................51
Microprocessor Support................................................................52
Trim Table........................................................................................54
Appendix A—Configuration Table..............................................55
Appendix B—Test Name Table.....................................................61
Outline Dimensions.......................................................................64
Ordering Guide..........................................................................64
REVISION HISTORY 3/04-Revision Sp0: Initial Version
5/04-Changed from Rev. Sp0 to Rev. A
Upd
GENERAL DESCRIPTION The ADM1041 is a secondary-side and management IC specifi-
cally designed to minimize external component counts and to
eliminate the need for manual calibration or adjustment on the
secondary-side controller. The principle application of this IC is
to provide voltage control, current share, and housekeeping
functions for single output in N+1 server power supplies.
The ADM1041 is manufactured with a 5 V CMOS process and
combines digital and analog circuitry. An internal EEPROM
provides added flexibility in the trimming of timing and voltage
and selection of various functions. Programming is done via an
SMBus serial port that also allows communication capability
with a microprocessor or microcontroller.
The usual configuration using this IC is on a one per output
basis. Outputs from the IC can be wire-ORed together or bused
in parallel and read by a microprocessor. A key feature on this
IC is support for an OrFET circuit when higher efficiency or
power density is required.
SAMPLE APPLICATION CIRCUIT DESCRIPTION Figure 1 shows a sample application circuit using the ADM1041.
The primary side is not detailed and the focus is on the secon-
dary side of the power supply.
The ADM1041 controls the output voltage from the power
supply to the designed programmed value. This programmed
value is determined during power supply design and is digitally
adjusted via the serial interface. Digital adjustment of the
current sense and current limit is also calibrated via the serial
interface, as are all of the internal timing specifications.
The control loop consists of a number of elements, notably the
inputs to the loop and the output of the loop. The ADM1041
takes the loop inputs and determines what, if any, adjustments
are needed to maintain a stable output. To maintain a stable
loop, the ADM1041 uses three main inputs: Remote voltage sense Load current sense Current sharing information
In this example, a resistor divider senses the output current as a
voltage drop across a sense resistor (RS) and feeds a portion
into the ADM1041. Remote local voltage sense is monitored via
VS+ and VS− pins. Finally, current sharing information is fed
back via the share bus. These three elements are summed
together to generate a control signal (VCMP), which closes the
loop via an optocoupler to the primary side PWM controller.
Another key feature of the ADM1041 is its control of an OrFET.
The OrFET causes lower power dissipation across the ORing
diode. The main function of the OrFET is to disconnect the
power supply from the load in the event of a fault occurring
during steady state operation, for example, if a filter capacitor or
rectifier fails and causes a short. This eliminates the risk of
bringing down the load voltage that is supplied by the redun-
dant configuration of other power supplies. In the case of a
short, a reverse voltage is generated across the OrFET. This
reverse voltage is detected by the ADM1041 and the OrFET is
shut down via the FG pin. This intervention prevents any
interruption on the power supply bus. The ADM1041 can then
be interrogated via the serial interface to determine why the
power supply has shut down.
This application circuit also demonstrates how temperature can
be monitored within a power supply. A thermistor is connected
between the VDD and MON2 pins. The thermistor’s voltage varies
with temperature. The MON2 input can be programmed to trip
a flag at a voltage corresponding to an overheating power supply.
The resulting action may be to turn on an additional cooling
fan to help regulate the temperature within the power supply.
04521-0-002
CURRENT
SENSE
CURRENT
REMOTE
SENSE
FROM
NOTES:1 HIGH VOLTAGE ANALOG I/O PIN2 STANDARD I/0 PIN3 ALL
OTENTIOMETERS ( )
ARE DIGITALLY PROGRAMMBALE THROUGH REGISTERSFigure 4. Chip Diagram, Part 2
