tea1750t-n1 NXP Semiconductors, tea1750t-n1 Datasheet - Page 6

• Manufacturer Part Number: tea1750t-n1
• Description: Tea1750 Greenchip Iii Smps Control Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TEA1750_1
Product data sheet
When the PFC is started, there is initially no supply take-over from the auxiliary winding.
To make a small V
as long as the flyback converter has not yet started. Regulation is done by hysteretic
control with a limited (high level) charge current. The hysteresis is typically 300 mV.
If during start-up the LATCH pin does not reach the V
V
again.
As soon as the flyback converter is started, the voltage on the FBCTRL pin is monitored. If
the output voltage of the flyback converter does not reach its intended regulation level in a
predefined time, the voltage on the FBCTRL pin reaches the V
is assumed. The TEA1750 then initiates a safe restart.
When one of the protection functions is activated, both converters stop switching and the
V
HV pin, but does not restart the converters. For a safe-restart protection, the capacitor is
recharged via the HV pin and the device restarts (see
In the event of an overvoltage protection of the PFC circuit
(V
VOSENSE pin voltage drops below V
detected (V
until V
When the voltage on pin V
stop switching and re-enter the safe restart mode. In the safe restart mode the driver
outputs are disabled and the V
th(UVLO)
CC
I
on pin VOSENSE > V
voltage drops to V
I
on pin VINSENSE > V
, the LATCH pin output is de-activated and the charge current is switched on
I
on pin VINSENSE < V
CC
capacitor possible, the V
th(UVLO)
Rev. 01 — 6 April 2007
ovp(VOSENSE)
CC
drops below the undervoltage lock-out level, both controllers
start(VINSENSE)
. A latched protection recharges the V
CC
pin voltage is recharged via the HV pin.
stop(VINSENSE)
), only the PFC controller stops switching until the
ovp(VOSENSE)
again.
CC
), only the PFC controller stops switching
voltage is regulated to the V
again. Also, if a mains undervoltage is
en(LATCH)
Figure
GreenChip III SMPS control IC
1)
to(FBCTRL)
level before V
CC
TEA1750
© NXP B.V. 2007. All rights reserved.
capacitor via the
level and an error
CC
startup
reaches
level,
6 of 29