TEA1716T
NXP Semiconductors
Resonant power supply control IC with PFC
Table 3.
State
Operating states
Description
No supply
Supply voltages on SUPIC and SUPHV are too low to provide any functionality. Undervoltage
protection (UVP-supplies; see Section 7.9) is active when VSUPHV < Vrst(SUPHV) and
V
SUPIC < Vrst(SUPIC). The IC is reset.
Disabled IC
IC is disabled because pin SSHBC/EN is LOW.
Thermal hold
Activated as long as OTP is active. IC is not operating. PFC and HBC controllers are disabled
and CSUPIC and CSUPREG are not charged.
SUPIC charge
SUPREG charge
Boost charge
HV start-up source charges IC supply capacitor (CSUPIC). CSUPREG is not charged.
Series regulator charges stabilized supply capacitor (CSUPREG).
Operational PFC builds up boost voltage.
Operational supply
Burst stop
Output voltage is generated. Both PFC and HBC controllers are fully operational.
Power-saving state for burst mode operation. PFC and HBC controllers are disabled and CSUPIC
is not charged. CSUPREG is charged.
Restart
Activated when a protection function is triggered. Restart timer is activated. During this time,
PFC and HBC controllers are disabled and CSUPREG is not charged. CSUPIC is charged.
Protection shut-down
Activated when a protection function is triggered. IC is not operational. PFC and HBC controllers
are disabled and CSUPIC and CSUPREG are not charged.
7.4 Enable input (pin SSHBC/EN)
The power supply application can be completely disabled by pulling pin SSHBC/EN LOW.
Figure 4 illustrates the internal functionality. When a voltage is present on pin SUPHV or
on pin SUPIC, a current Ipu(EN) (42 A typical) flows out of SSHBC/EN. If the pin is not
pulled-down, this current lifts the voltage up to Vpu(EN) (3 V typical). Since this voltage is
above both Ven(PFC)(EN) (1.2 V typical) and Ven(IC)(EN) (2.2 V typical), the IC is completely
enabled.
The IC can be completely disabled by pulling the voltage on SSHBC/EN down below both
Ven(PFC)(EN) and Ven(IC)(EN) via an optocoupler driven from the secondary side of the HBC
transformer (see Figure 4). The PFC controller stops switching immediately, but the HBC
controller continues switching until the low-side stroke is active. It is also possible to
control the voltage on SSHBC/EN from another circuit on the secondary side via a diode.
The external pull-down current must be larger than the internal soft start charge current
Iss(hf)(SSHBC)
.
If the voltage on SSHBC/EN is pulled down below Ven(IC)(EN), but not below Ven(PFC)(EN)
only the HBC is disabled. This feature can be useful when another power converter is
connected to the boost voltage of the PFC.
,
The low-side power switch of the HBC is on when the HBC is disabled via the SSHBC/EN
pin.
TEA1716T
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Objective data sheet
Rev. 1 — 27 January 2012
11 of 46
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