tea1791t/n1 NXP Semiconductors, tea1791t/n1 Datasheet - Page 7

• Manufacturer Part Number: tea1791t/n1
• Description: Greenchip Synchronous Recti?er Controller
• Manufacturer: NXP Semiconductors

NXP Semiconductors
11. Application information
TEA1791T_1
Product data sheet
A switched mode power supply with the TEA1791T consists of a primary side
discontinuous conduction mode flyback controller, a transformer, and an output stage with
a feedback circuit. In the output stage a MOSFET (Qsec) is used for low conduction
losses. The MOSFET is controlled by the TEA1791T.
The timing for the synchronous rectifier switch is derived from the voltage sensed on the
SRSENSE pin. The resistor in the SRSENSE connection is needed to protect the
TEA1791T from excessive voltages. The SRSENSE resistor should typically be 1 k .
Higher values might impair correct timing, lower values may not provide sufficient
protection.
Fig 4.
V
Application diagram
in
CONTROLLER
PRIMARY
SIDE
Rev. 01 — 3 February 2009
Q prim
TR
GreenChip synchronous rectifier controller
V
CC
GND
TEA1791T
DRIVER
Qsec
SRSENSE
R SRSENSE
TEA1791T
© NXP B.V. 2009. All rights reserved.
014aaa702
C out
V
out
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