HandleElectronicsCo.,Ltd.
Tel:852-26378080
EtronElectronicsTechnologyCo.,Ltd
Tel:020-36471221
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TF12A
Low Power OFF-Line SMPS Primary Switcher
Features
Description
The TF12A is a low power primary switcher best suitable
for Off-line SMPS battery charger adapters, auxiliary power
supplies for industrial systems and standby power supplies for
TVs or monitors . It consists of a dedicated current mode PWM
controller and a high-voltage Power MOSFET.
VDD range: 9V to 38V
60 kHz fixed frequency operation
Current-mode control
Auxiliary under-voltage lockout with hysteresis
High-voltage start-up current source
Over-voltage, over-current and over-temperature
protection with auto-restart
Industrial temperature range: -40 °C to +85 °C
Drop-in replacement for the VIPer12A
The TF12A operates at fixed 60 kHz switching frequency.
Its control circuitry provides large VDD range desired in
applications in which auxiliary power supply changes are
expected. It also provides over-voltage, over-current and over-
temperature protection.
The TF12A is offered in 8-pin PDIP and SOIC narrow packages.
It operates over an extended -40 °C to +85 °C temperature
range.
Applications
Switch Mode Power Supplies
Auxiliary Power Supplies for Industrial Systems
Adapters for Portable Electronics
Ordering Information
PART NUMBER PACKAGE PACKING
Year Year Week Week
(qty) MARK
YYWW
TF12A-3AS
PDIP-8
Tube,
50
TF12
Typical Power Capability
Lot ID
MAINS TYPE
PDIP-8
13W
SOIC-8
8W
YYWW
TF12
Lot ID
TF12A-TAU
TF12A-TAH
SOIC-8(N) Tube,
95
European (195 - 265 Vac)
Universal (85 - 265 Vac)
SOIC-8(N) Tape & Reel, 2500
8W
5W
Function Diagram
VDD
DRAIN
ON/OFF
60 kHz
Oscillator
Regulator
S
Over-
Temperature
Detector
R1
R2
FF
Q
Internal
Supply
PWM
Latch
R3
R4
+
-
Blanking
-
8/14.5V
42V
+
0.23V
Over-Voltage
Latch
R
+
-
S
FF
Q
1 k
230
FB
SOURCE
1
June 2011