NXP Semiconductors AN10907, Примечание к применению

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AN10907 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2010. All rights reserved.
Application note Rev. 1 — 28 December 2010 59 of 82
NXP Semiconductors
AN10907
TEA1613T resonant power supply control IC
10. Protection functions
Most protection functions are discussed in the sections of the systems of which they are a
part. In the overview
Table 3 , links to the corresponding places in this document are given.
In the following paragraphs the remaining, more independent, protection functions are
discussed.
10.1 Protection overview
10.2 IC protection
10.2.1 OverTemperature Protection (OTP)
The TEA1613T contains an accurate internal OverTemperature Protection (OTP). When
the junction temperature exceeds the overtemperature level of 140

C, the IC goes to the
thermal hold state. The thermal hold state is left as soon as the temperature has dropped
by 10

C.
The circuit resumes operation with a complete restart including a soft-start.
10.2.2 Latched protection
Only an OVP detection on SNSOUT/PFCON, leads to a latched shutdown protection
state. To initiate this, the voltage on SNSOUT/PFCON must exceed 3.5 V.
Resetting a latched protection shutdown state
When a latched protection shutdown state has occurred this state is reset by one of the
following actions:
•
SUPIC drops below 7 V and SUPHV is lower than 7 V
•
SSHBC/EN is pulled below 2.2 V (enable level)
Table 3. Overview of protection functions with links
Part Symbol Protection Action Link
IC UVP-SUPIC undervoltage protection SUPIC IC disable 6.2.2
IC UVP-SUPREG undervoltage protection SUPREG IC disable 6.5
IC UVP supplies undervoltage protection supplies IC disable and reset 6.2.2
IC SPC-SUPIC short-circuit protection SUPIC low HV start-up current 6.2.2
IC OVP output overvoltage protection output IC shutdown 10.3.1
IC UVP output undervoltage protection output IC restart after protection time 10.3.2
IC OTP overtemperature protection IC disable 10.2.1
HBC UVP-boost undervoltage protection boost HBC disable 8.1
HBC OLP-HBC open-loop protection HBC IC restart after protection time 8.5.1
HBC HFP-HBC high frequency protection HBC IC restart after protection time 8.4.4
HBC OCR-HBC overcurrent regulation HBC HBC increase frequency
IC restart after protection time
8.7.1
HBC OCP-HBC overcurrent protection HBC HBC step to maximum frequency 8.7.2
HBC CMR capacitive mode regulation HBC increase frequency 8.3.2
HBC ANO adaptive non-overlap HBC prevent hazardous switching 8.3.1