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AN10881
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© NXP B.V. 2011. All rights reserved.
Application note
Rev. 2 — 26 September 2011
87 of 102
NXP Semiconductors
AN10881
TEA1713 resonant power supply control IC with PFC
•
SNSOUT:
The voltage on this pin must be between 2.35 V and 3.5 V for normal operation. A
voltage can be forced on pin SNSOUT to avoid protection. But it is often related (by a
resistive divider) to the SUPIC and is correct when SUPIC is supplied externally.
•
RCPROT:
Several protection functions charges the timer.
11.2.2 PFC only
Keeping SSHBC/EN below or forcing it to drop below 2.2 V can disable the HBC function.
A voltage higher than 1.2 V can enable the PFC function. Applying an additional voltage
(from an external supply) of approximately 1.5 V on SSHBC/EN enables PFC only
operation.
The setup is similar to the HBC only operation setup, but for extra safety, the V
BOOST
connection to the high side switch of the HBC can be disconnected. In addition, a small
load can be connected on V
BOOST
to prevent voltage overshoot and control the output
power capability.
11.2.2.1
Operational check without mains voltage
Without mains input voltage, by lowering the (external) voltage on SNSMAINS and
SNSBOOST to below 2.5 V, drive pulses can be observed on GATEPFC. Lower voltages
lead to a longer on-time. Below 0.89 V, pulses stop because of SNSMAINS undervoltage
protection and restarts when the level increases above 1.15 V.
Fig 61. Start-up/debugging for PFC only
001aal102
V
ext
= 25 V
DC
V
ext
= 1.5 V
DC
external
SUPIC
supply
disable
protection
timer
apply non-
protection
sense voltage
(if needed)
enable PFC and
disable HBC start
optional: remove
VBOOST connection
to high side MOSFET
COMPPFC
1
24
SNSBOOST
TEA1713
SNSMAINS
2
23
RCPROT
SNSAUXPFC
3
22
SSHBC/EN
SNSCURPFC
4
21
SNSFB
SNSOUT
5
20
RFMAX
SUPIC
6
19
CFMIN
GATEPFC
7
18
SGND
PGND
8
17
SNSCURHBC
SUPREG
9
16
n.c.
GATELS
10
15
HB
n.c.
11
14
SUPHS
SUPHV
12
13
GATEHS