TEA1762T NXP Semiconductors, TEA1762T Datasheet - Page 10

• Manufacturer Part Number: TEA1762T
• Description: GreenChip synchronous rectifier controller
• Manufacturer: NXP Semiconductors

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11. Application information
TEA1762T_2
Product data sheet
Fig 5. Application example TEA1762T
V
in
CONTROLLER
PRIMARY
SIDE
A switched mode power supply with the TEA1762T 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 TEA1762T. The output voltage and/or current is
also controlled by the TEA1762T via the opto coupler connection to the primary side. See
Figure
The output voltage is set by resistors R
resistor R
sensed on the SRSENSE pin. The resistor in the SRSENSE connection is needed to
protect the TEA1762T from excessive voltages. The SRSENSE resistor should typically
be 1 k . Higher values might impair correct timing, lower values may not provide sufficient
protection.
During output short circuit or load connection, the limiting values on pin SENSEGND must
not be exceeded.
OPTO1
OPTO2
Q prim
TR
5.
isense
Q sec
R srsense
. The timing for the synchronous rectifier switch is derived from the voltage
R opto
OPTOPROT
SRSENSE
DRIVER
Rev. 02 — 25 April 2007
POWERGND
V
CC
R isense
TEA1762T
fb1
OPTOREG
and R
ISENSE
GreenChip synchronous rectifier controller
fb2
. The output current is controlled by the
SENSEGND
VREF
PROTECT
VSENSE
C fb
TEA1762T
© NXP B.V. 2007. All rights reserved.
t
R fb1
R fb2
014aaa058
C out
V
out
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