NCP1562: PWM Controller, High Performance, Active Clamp / Reset

The NCP1562x is a family of voltage mode controllers designed for dc-dc converters requiring high efficiency and low parts count. These controllers incorporate two in phase outputs with an overlap delay to prevent simultaneous conduction and facilitates soft switching. The main output is designed for driving a forward converter primary MOSFET. The secondary output is designed for driving an active clamp circuit MOSFET, a synchronous rectifier on the secondary side, or an asymmetric half bridge circuit. The NCP1562 family reduces component count and system size by incorporating high accuracy on critical specifications such as maximum duty cycle limit, undervoltage detector and overcurrent threshold. Two distinctive features of the NCP1562 are soft-stop and a cycle skip current limit with a time threshold. Softstop circuitry powers down the converter in a controlled manner if a severe fault is detected. The cycle skip detector enables a softstop sequence if a continuous overcurrent condition is present. Additional features found in the NCP1562 include line feedforward, frequency synchronization up to 1.0 MHz, cycle by cycle current limit with leading edge blanking (LEB), independent under and overvoltage detectors, adjustable output overlap delay, programmable maximum duty cycle, internal startup circuit and soft-start.

Features
  • Soft-Stop Powers Down Converter in a Controlled Manner
  • Independent Line Undervoltage and Overvoltage Detectors
  • Programmable Maximum Volt-Second Product
  • Programmable Soft-Start
  • Internal 100 V Startup Circuit
  • Dual Outputs with Adjustable Overlap Delay
  • >2 A Output Drive Capability
  • Cycle-by-Cycle Current Limit
  • Cycle Skip Initiated if Continuous Current Limit Condition Exists
  • Voltage Mode Operation with Input Voltage Feedforward
  • Fixed Frequency Operation up to 1 MHz
  • Bidirectional Frequency Synchronization
  • Accurate Programmable Maximum Duty Cycle
  • Precision 5 V Reference
Benefits
  • Eliminates Resonance Between Active Clamp Capacitor and Primary Inductance
  • Reduces External components
  • Prevents Transformer Saturation
  • Reduces Stress During Power Up
  • Eliminates the Need for External Components
Applications
  • High power isolated DC/DC converters
  • Power supplies
End Products
  • Desktop / Server PSU
  • Telecom base station PSU
  • Flat TV PSU
Design & Development Tools (1)
Document TitleDocument ID/SizeRevisionRevision Date
NCP1562 Design WorksheetNCP1562 DWS.XLS (237.0kB)5
Package Drawings (2)
Document TitleDocument ID/SizeRevision
SOIC 16 LEAD751B-05 (38.2kB)K
TSSOP-16948F-01 (41.7kB)B
Application Notes (1)
Document TitleDocument ID/SizeRevisionRevision Date
Design of Active Clamp Forward of DC-DC Converter using NCP1562AND8273/D (403.0kB)3
Evaluation Board Documents (5)
Document TitleDocument ID/SizeRevisionRevision Date
NCP1562-100WGEVB ManualEVBUM2148/D (1230.0kB)2
NCP1562-100WGEVB Bill of Materials ROHS CompliantNCP1562-100WGEVB_BOM_ROHS.PDF (122kB)2
NCP1562-100WGEVB Gerber Layout Files (Zip Format)NCP1562-100WGEVB_GERBER.ZIP (126.0kB)0
NCP1562-100WGEVB SchematicNCP1562-100WGEVB_SCHEMATIC.PDF (680.0kB)0
NCP1562-100WGEVB Test ProcedureNCP1562-100WGEVB_TEST_PROCEDURE.PDF (4580.0kB)0
Data Sheets (1)
Document TitleDocument ID/SizeRevisionRevision Date
PWM Controller, High Performance, Active Clamp / ResetNCP1562A/D (477.0kB)5
Evaluation/Development Tool Information
ProductStatusComplianceShort Description
NCP1562-100WGEVBActivePb-free100 W / 48 V Telecom Brick Evaluation Board
Order Information
ProductStatusCompliancePackageMSL*ContainerBudgetary Price/Unit
NCP1562ADBR2GActivePb-free Halide freeTSSOP-16948F-011Tape and Reel2500$1.3333
NCP1562ADR2GActivePb-free Halide freeSOIC-16751B-051Tape and Reel2500$1.3333
NCP1562BDBR2GActivePb-free Halide freeTSSOP-16948F-011Tape and Reel2500$1.3333
NCP1562BDR2GActivePb-free Halide freeSOIC-16751B-051Tape and Reel2500$1.3333
Specifications
ProductTopologyControl Modefsw Typ (kHz)Stand-by ModeUVLO (V)Short Circuit ProtectionLatchSoft StartVCC Max (V)Drive Cap. (mA)
NCP1562ADBR2GFlybackVoltage ModeUp to 500NoYesYesYesYes202500 / 2500
NCP1562ADR2GFlybackVoltage ModeUp to 500NoYesYesYesYes202500 / 2500
NCP1562BDBR2GFlybackVoltage ModeUp to 500NoYesYesYesYes202500 / 2500
NCP1562BDR2GFlybackVoltage ModeUp to 500NoYesYesYesYes202500 / 2500
PWM Controller, High Performance, Active Clamp / Reset (477.0kB) NCP1562
NCP1562 Design Worksheet NCP1562
Design of Active Clamp Forward of DC-DC Converter using NCP1562 NTMFS4935N
EVBUM2148/D - 1230 NCP1562-100WGEVB
NCP1562-100WGEVB BOM ROHS NCP1562-100WGEVB
NCP1562-100WGEVB GERBER NCP1562-100WGEVB
NCP1562-100WGEVB SCHEMATIC NCP1562-100WGEVB
NCP1562-100WGEVB TEST PROCEDURE NCP1562-100WGEVB
TSSOP-16 MC14504B
SOIC 16 LEAD MC14504B
NCP1562