tea1752t NXP Semiconductors, tea1752t Datasheet - Page 13

• Manufacturer Part Number: tea1752t
• Description: Greenchip Iii Smps Control Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TEA1752T_LT
Product data sheet
7.2.12 PFC open-loop protection (VOSENSE pin)
7.2.13 Driver (pin PFCDRIVER)
7.2.11 Overvoltage protection (VOSENSE pin)
7.3.1 Multimode operation
7.3 Flyback controller
The voltage on pin VINSENSE is clamped to a minimum value,
V
after a mains dropout.
An overvoltage protection circuit is incorporated to prevent output overvoltage during load
steps and mains transients.
When voltage on the VOSENSE pin exceeds the V
power factor correction circuit is inhibited. Switching of the PFC recommences when the
VOSENSE pin voltage drops back below the V
When the resistor between pin VOSENSE and ground is open, the overvoltage protection
is also triggered.
The power factor correction circuit will not start switching until the voltage on the
VOSENSE pin is above the V
and VOSENSE short circuit situations.
The driver circuit to the gate of the power MOSFET has a current sourcing capability of
typically −500 mA and a current sink capability of typically 1.2 A. This enables fast turn-on
and turn-off of the power MOSFET for efficient operation.
The TEA1752(L)T includes a controller for a flyback converter. The flyback converter
operates in quasi-resonant or discontinuous conduction mode with valley switching. The
auxiliary winding of the flyback transformer provides demagnetization detection and
powers the IC after start-up.
The TEA1752(L)T flyback controller can operate in several modes (see
start(VINSENSE)
+ ΔV
All information provided in this document is subject to legal disclaimers.
pu(VINSENSE)
Rev. 02 — 24 June 2010
th(ol)(VOSENSE)
, for a fast restart when mains input voltage is restored
TEA1752T; TEA1752LT
level. This protects the circuit from open-loop
ovp(VOSENSE)
ovp(VOSENSE)
GreenChip III SMPS control IC
level.
level, switching of the
© NXP B.V. 2010. All rights reserved.
Figure
8).
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