NXP Semiconductors AN10907, Application Note

Page: 81 / 82

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 81 of 82
NXP Semiconductors
AN10907
TEA1613T resonant power supply control IC
Fig 61. Overview of the functions in the circuit diagram
of the TEA1613T application . . . . . . . . . . . . . . . .77
17. Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Scope and setup of this document . . . . . . . . . . 3
1.2 Related documents. . . . . . . . . . . . . . . . . . . . . . 3
2 TEA1613T highlights and features . . . . . . . . . . 4
2.1 Resonant conversion . . . . . . . . . . . . . . . . . . . . 4
2.2 General features . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 Resonant half-bridge controller features. . . . . . 5
2.4 Protection features . . . . . . . . . . . . . . . . . . . . . . 5
2.5 Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6 Typical areas of application . . . . . . . . . . . . . . . 5
3 Pin overview with functional description . . . . 6
4 Application diagram . . . . . . . . . . . . . . . . . . . . . 9
5 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Supply functions . . . . . . . . . . . . . . . . . . . . . . . 12
6.1 Basic supply system overview . . . . . . . . . . . . 12
6.1.1 TEA1613T supplies . . . . . . . . . . . . . . . . . . . . 12
6.1.2 Supply monitoring and protection . . . . . . . . . . 12
6.2 SUPIC - the low voltage IC supply . . . . . . . . . 13
6.2.1 SUPIC start-up . . . . . . . . . . . . . . . . . . . . . . . . 13
6.2.2 SUPIC stop, UVP and short-circuit
protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.2.3 SUPIC current consumption . . . . . . . . . . . . . . 13
6.3 SUPIC supply using HBC transformer auxiliary
winding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.3.1 Start-up by SUPHV . . . . . . . . . . . . . . . . . . . . . 14
6.3.2 Block diagram for SUPIC start-up. . . . . . . . . . 14
6.3.3 Auxiliary winding on the HBC transformer . . . 15
6.3.3.1 SUPIC and SNSOUT/PFCON by auxiliary
winding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.3.3.2 Auxiliary supply voltage variations by output
current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.3.3.3 Voltage variations by auxiliary winding
position: primary side component . . . . . . . . . . 16
6.3.4 Difference between UVP on SNSOUT/PFCON
and SNSCURHBC OCP/OCR . . . . . . . . . . . . 17
6.4 SUPIC supply by external voltage . . . . . . . . . 17
6.4.1 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.4.2 Stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.5 SUPREG . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.5.1 Block diagram of SUPREG regulator . . . . . . . 19
6.5.2 SUPREG during start-up . . . . . . . . . . . . . . . . 19
6.5.3 Supply voltage for the output drivers:
SUPREG . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.5.4 Supply voltage for the output drivers:
SUPHS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.5.4.1 Initial charging of SUPHS . . . . . . . . . . . . . . . . 20
6.5.4.2 Current load on SUPHS . . . . . . . . . . . . . . . . . 20
6.5.4.3 Lower voltage on SUPHS . . . . . . . . . . . . . . . . 21
6.5.5 SUPREG power consumed by MOSFET
drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.5.6 SUPREG supply voltage for other circuits . . . 22
6.6 Value of the capacitors on SUPIC, SUPREG
and SUPHS . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.6.1 Value of the capacitor on SUPIC . . . . . . . . . . 23
6.6.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.6.1.2 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.6.1.3 Normal operation . . . . . . . . . . . . . . . . . . . . . . 23
6.6.1.4 Burst mode operation. . . . . . . . . . . . . . . . . . . 23
6.6.2 Value of the capacitor on SUPREG . . . . . . . . 24
6.6.3 Value of the capacitor for SUPHS . . . . . . . . . 24
6.6.4 Relationship between the capacitors on
SUPIC, SUPREG and SUPHS . . . . . . . . . . . 24
7 MOSFET drivers GATELS and GATEHS . . . . 25
7.1 GATELS and GATEHS. . . . . . . . . . . . . . . . . . 25
7.2 Supply voltage and power consumption . . . . 25
7.3 General details regarding MOSFET drivers . . 26
7.4 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 27
8 HBC functions . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.1 SNSBOOST undervoltage or brownout
protection level. . . . . . . . . . . . . . . . . . . . . . . . 28
8.1.1 Start and stop voltage without series
resistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.1.2 Start and stop voltage with series
resistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.1.3 SNSBOOST and compensation
SNSBURST . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.2 HBC switch control. . . . . . . . . . . . . . . . . . . . . 29
8.3 HBC adaptive non-overlap. . . . . . . . . . . . . . . 30
8.3.1 Inductive mode (normal operation) . . . . . . . . 30
8.3.2 Capacitive mode . . . . . . . . . . . . . . . . . . . . . . 31
8.3.3 Capacitive Mode Regulation (CMR) . . . . . . . 32
8.4 HBC oscillator . . . . . . . . . . . . . . . . . . . . . . . . 34
8.4.1 Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.4.2 Operational control. . . . . . . . . . . . . . . . . . . . . 34
8.4.3 CFMIN and RFMAX . . . . . . . . . . . . . . . . . . . . 35
8.4.3.1 Minimum frequency setting for CFMIN . . . . . 35
8.4.3.2 Maximum frequency setting for RFMAX . . . . 36
8.4.4 RFMAX and High Frequency Protection
(HFP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
8.5 HBC feedback (SNSFB) . . . . . . . . . . . . . . . . 37
8.5.1 HBC Open Loop Protection (OLP). . . . . . . . . 38
8.6 SSHBC/EN soft-start and enable . . . . . . . . . . 39
8.6.1 Switching on and off using an external
control function. . . . . . . . . . . . . . . . . . . . . . . . 39
8.6.1.1 Switching on and off using SSHBC/EN . . . . . 40
8.6.1.2 Hold and continue . . . . . . . . . . . . . . . . . . . . . 40
8.6.2 Soft-start HBC . . . . . . . . . . . . . . . . . . . . . . . . 40
8.6.2.1 Soft-start voltage levels . . . . . . . . . . . . . . . . . 41
8.6.2.2 SSHBC/EN charge and discharge . . . . . . . . . 41
8.6.2.3 SNSFB, SSHBC/EN and soft-start reset -
operating frequency control . . . . . . . . . . . . . . 42
8.6.2.4 Soft-start reset . . . . . . . . . . . . . . . . . . . . . . . . 42
8.7 Overcurrent protection and regulation HBC. . 43