tea1752t NXP Semiconductors, tea1752t Datasheet - Page 28

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

NXP Semiconductors
11. Application information
TEA1752T_LT
Product data sheet
A power supply with the TEA1752(L)T consists of a power factor correction circuit
followed by a flyback converter (See
Capacitor C
rectified mains supply during start-up and via the auxiliary winding of the flyback converter
during operation. Sense resistors R
MOSFETs S1 and S2 into a voltage on pins PFCSENSE and FBSENSE. The values of
R
In the example shown in
Temperature Coefficient (NTC) resistor. When the resistance drops below
connected to the FBCTRL pin. Time-out protection is activated typically after 10 ms for a
120 nF capacitor. R
normal regulation loop.
R
due to negative voltage spikes across the sense resistors.
Resistor R
V
-------------------------------
SENSE1
I
S1
prot LATCH
O LATCH
(
and R
(
and R
)
S2
AUX1
)
VCC
prevent the soft start capacitors from being charged during normal operation
=
SENSE2
protects the IC from damage during events such as lightning strikes.
All information provided in this document is subject to legal disclaimers.
15.6 kΩ typical
buffers the IC supply voltage, which is powered via the high voltage
LOOP
define the maximum primary peak current on MOSFETs S1 and S2.
Rev. 02 — 24 June 2010
(
Figure
is added so the time-out capacitor does not interfere with the
18, the LATCH pin is connected to a Negative
)
, the protection is activated. A capacitor C
SENSE1
Figure
TEA1752T; TEA1752LT
and R
18).
SENSE2
convert the current through
GreenChip III SMPS control IC
© NXP B.V. 2010. All rights reserved.
TIMEOUT
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is