Secondary-Side Controller with
Current Share and Housekeeping

ADM1041


Rev. A
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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 (I
2
C 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
PWM
CONTROLLER
V
DD
V
DD
BIAS
MICRO-
CONTROLLER
V
DD
V
OUT
GND
OrFET
R
LOAD
V
DD
V
S
+
V
S
–
V
OUT
SHARE BUS
THERMISTOR
V
DD
C
S
–/V
LS
C
CMP
V
CMP
ICT
PULSE
MON2
CBD
PEN
GND
SCL
SHRO
SHRS
F
G
F
D
AC_OK
DC_OK
PSON
ADD0
SDA
ADM1041
ISOLATION BARRIER
OTP
V
DD
04521-0-031
V
DD
OPTIONAL
C
S
+
V
S
+
V
S
–
SCMP
RS

Figure 1. Typical Application Circuit