Document
UNISONIC TECHNOLOGIES CO., LTD S3525
PC POWER SUPPLY SUPERVISOR
DESCRIPTION
The UTC S3525 is specially designed for switching power supply system. it provides protection circuits, power good output (PGO) indicator, fault protection output (FPOB) and a PSONB control.
The protection circuits include over voltage protection (OVP), under voltage protection (UVP) and over current protection (OCP) monitoring for system voltages and currents.
When 3.3V, 5V or 12V voltage is decreasing to 2.68V, 4.3V and 9.9V respectively, the under voltage protection (UVP) function will be enabled. FPOB will be set to high to turn off the PWM controller IC. Toggling the PSONB from low to high will reset the fault protection latch.
The voltage difference across external current shunt is used for OCP functions. An external resistor can be used to adjust protection threshold.
The power supply is turned on after 38mS delay time when PSONB signal is set from high to low. To turn off power supply, PSONB signal is set from low to high with the delay time 38mS. The PGI circuitry provides a power-down warning signal for PGO. When PGI input is lower than the internal 1.20V reference voltage, PGO signal is pulled low.
FEATURES
* OVP/UVP monitors 3.3V, 5V, 12V input voltage level. * OCP monitors IS33, IS5, IS12 input current sense. * Fault protection output (FPOB) with Open Drain Output stage. * Power good output (PGO) with Open Drain Output stage. * 38ms de-bounce time for PSONB input signal. * 300ms time delay from PGI to PGO. * 2.4ms time delay for PSONB to turn off FPOB.
ORDERING INFORMATION
Ordering Number
Lead Free Plating
Halogen Free
S3525L-D14-T
S3525G-D14-T
S3525L-S14-R
S3525G-S14-R
S3525L-S14-T
S3525G-S14-T
Package
DIP-14 SOP-14 SOP-14
CMOS IC
Packing Tube
Tape Reel Tube
www.unisonic.com.tw Copyright © 2010 Unisonic Technologies Co., Ltd
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QW-R502-105.B
S3525
PIN ASSIGNMENT
CMOS IC
FUNCTION DESCRIPTION
PGI
PSONB
UV&OC Protection OV Protection
PGI<1.2V
L
No No
PGI<1.2V
L
No Yes
PGI<1.2V
L
Yes No
PGI<1.2V
L
Yes Yes
PGI>1.2V
L
No No
PGI>1.2V
L
No Yes
PGI>1.2V
L
Yes No
PGI>1.2V
L
Yes Yes
XHXX
Note: FPOB=L means: fault is not latched. FPOB=H means: fault is latched
PGO=L means: fault. PGO=H means: No fault
X=do not care
FPOB L H L H L H H H H
PGO L L L L H L L L L
PIN DESCRIPTIONS
PIN NO. 1 2 3
PIN NAME PGI GND FPOB
4 PSONB
5 IS12AB
6 RI
7 V12B 8 IS5 9 IS33 10 V12A 11 V33 12 V5 13 VDD
14 PGO
TYPE
Input
Supply
Output
Input
Input
Input
Input Input Input Input Input Input Supply
Output
DESCRIPTION Power Good Input. For ATX SMPS, it detects AC line voltage through the main transformer. Ground Fault Protection Output. Output signal to control the primary PWM IC through an opto-coupler. When FPOB is low, the PWM IC is enabled. Remote On/Off logic input from CPU or main-board. The power supply will be turned on/off after 38mS delay. 12V AB over current protection. Reference setting. One external resistor Ri connected between RI and GND pin will determine a reference current, IREF = 1.20/Ri, for OCP programming. 12V over/under voltage protection. 5V over current protection. 3.3V over current protection 12V over/under voltage protection. 3.3V over/under voltage protection 5V over/under voltage protection. Power supply. Power good logic output, 0 or 1(open-drain). Power good=1 means that the power supply is good for operation. The power good delay is 300mS.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
2 of 9
QW-R502-105.B
S3525
BLOCK DIAGRAM
PGI Bandgap Reference VREF=1.2V
IS33 VS33
IS12AB VS12A
VS12B
IS5 VS5
+- UN
V12A + IREF*8 + -OV
+-UN V12A + -
IREF*8 + -OV
+-UN V12A + -
+ -OV
+-UN V12A + IREF*8 + -OV
+-UN
CMOS IC
73 μs debounce
225ms clr
delay
V cc PGO
73 μs debounce
RQ SQ
FPOB
Power On Reset
Internal PWR Power
VCCI=3.6V
2.4ms delay
38 ms debounce
PSONB
75ms/ 300ms delay
PWR OSC
CLK
V12A
VREF=1.2V
+ -
RI
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
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QW-R502-105.B
S3525
CMOS IC
ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
RATINGS
UNIT
Supply Voltage, VDD, V12A Input Voltage
V5,V33, PSONB, IS5, IS33 IS12AB, V12B PGI
VIN
-0.3 ~ 16 -0.3 ~ 7 -0.3 ~ 16 -0.3 ~ VDD+0.3
V V V V
Output Voltage
FPOB PGO
VOUT
-0.3 ~ 7 -0.3 ~ 7
V V
Operating Temperature
TOPR
-40 ~ +125
°C
Storage Temperature
TSTG
-55 ~ +150
°C
Note Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
RECOMMENDED OPERATING CONDITIONS
Supply Voltage VDD Supply Voltage VCC2
Input Voltage
PARAMETER
Output Voltage
Output Sink Current
RI Output Current Supply Voltage Rising Time (VDD)
SYMBOL VDD
V5,V33 ,PGI ,PSONB V12A, V12B FPOB PGO FPOB PGO
VIN
VOUT
IO(SINK) IO(RI)
tR
MIN 4 9.5
10 1
TYP 12 12
ELECTRICAL CHARACTERISTICS (Ta=25°C and VDD=5V and V12A=12V)
MAX 15 15 7 15 7 7 30 10 65
UNIT V V V V V.