Green mode PWM IC
FA8A84N / 85N / 94N / 95N
1. Overview
Datasheet
FA8A84N/85N/94N/95N is a current mode type switching power supply control IC possible to drive a power MOSFET
directly. Despite of a small package with 8 pins, it has a lot of functions and it is best suited for power saving at the light load
and decreasing external parts. Moreover it enables to realize a reduced space and a high cost-performance power supply.
2. Features
▆ Realization of low standby power
• Built-in discharge function for AC input filter capacitor (XCAP).
(Reduce loss of the discharge resistor)
• Integrated frequency decrease function improves efficiency
in the middle-load region. (Frequency decrease start point is
adjustable based on the settings of mounted parts.)
• Intermittent operation (burst operation) system adopted for light load
operation achieves low standby power. (Burst operation start point is
5.0 0.25
adjustable based on the settings of mounted parts.)
• Switching is allowed between normal operation mode and power-off mode.
In power-off mode, lower standby power is ensured.
• Built-in 650V high voltage startup circuit.
1.27
▆ Various Protection are built in.
• Overload protection (Auto recovery, Latch)
• Integrated function of correcting overload detection level depending on
Package:SOP-8
AC input voltage
(Correction amount is adjustable based on the settings of externally mounted parts.)
• Integrated latch-off function based on external signals, overvoltage protection function, low-voltage prevention
function, and overheat protection function
• Internal Soft-Start
• The lowest frequency is set to 26 kHz to prevent operation at audible frequency under light load.
▆ Switching frequency jitter function realize low EMI.
▆ Internal DSS (Dynamic Self Supply)
▆ Drive circuit for MOSFET: -0.5A(sink)/0.5A(source)
Function list by types
Discharge
function for X-
Capacitor
External latch, over-
voltage protection, Over
heat protection
Brown out
protection
Type
Overload protection
Frequency
100kHz
FA8A84N
FA8A85N
FA8A94N
FA8A95N
Automatic recovery
Latch
Automatic recovery
Latch
No
Latch
Latch
No
No
Yes
3. Application circuit example
AC Input
Vout
8
7
6
5
VH
(NC)
VCC
OUT
FA8A84N
LAT
1
FB
2
CS
3
GND
4
© Fuji Electric Co., Ltd. All rights reserved.
July,2016 DS-172E Rev1.0
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