NCP1246: Fixed Frequency Current Mode Controller for Flyback Converters

The NCP1246 is a new fixed-frequency current-mode controller featuring Dynamic Self-Supply. This function greatly simplifies the design of the auxiiary supply and the Vcc capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stnad-by etc. This device contains a special HV detector which detects the application unplug from the AC input line and triggers the X2 discharge current. The HV structure also includes brown-out detection circuitry. The NCP1246 features a timer-based fault detection that ensures the detection of overload and an adjustable power compensation to help keep the maximum power independent of the input voltage. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for robust power supply designs. A dedicated off mode allows the SMPS to reach extremely low no load input power consumption when combinded with secondary side contoller NCP4353 or NCP4354. When used together, the SMPS is capable of achieving <10 mW no load input power consumption. The secondary side contoller signals the NCP1246 to enter a sleep mode, minimizing the power consumption of the control circuitry.

技术特性
  • Fixed−Frequency Current−Mode Operation (65 kHz and 100 kHz frequency options)
  • Frequency Foldback then Skip Mode for Maximized Performance in Light Load and Standby Conditions
  • Timer−Based Overload Protection with Latched (Option A) or Auto−Recovery (Option B) Operation
  • High−voltage Current Source with Brown−Out Detection and Dynamic Self−Supply, Simplifying the Design of the VCC Circuitry
  • Frequency Modulation for Softened EMI Signature
  • Adjustable Overpower Protection Dependant on the Bulk Voltage
  • Latch−off Input Combined with the Overpower Protection Sensing Input
  • VCC Operation up to 28 V, With Overvoltage Detection
  • 500/800 mA Source/Sink Drive Peak Current Capability
  • 10 ms Soft−Start
  • Internal Thermal Shutdown
  • No−Load Standby Power < 30 mW
  • X2 Capacitor in EMI Filter Discharging Feature
应用
  • AC-DC Adapters
  • LCD TV power supplies
终端产品
  • Notebook Computers
封装图 PACKAGE DIMENSIONS

NCP1246封装图

评估板信息
评估板 状况 无铅(Pb-free) 简短说明
NCP4354AADAPGEVB Active Pb-free ADPTR 65W OFFMODE CNT DB
订购信息 Ordering Information
产品 状况 Compliance 具体说明 封装 MSL* 容器 预算价格 (1千个数量的单价)
类型 外形 类型 数量
NCP1246AD065R2G Active
Pb-free
Halide free
Fixed Frequency Current Mode Controller for Flyback Converters SOIC-8 751U 1 Tape and Reel 2500 $0.5
NCP1246AD100R2G Active
Pb-free
Halide free
Fixed Frequency Current Mode Controller for Flyback Converters SOIC-8 751U 1 Tape and Reel 2500 $0.5
NCP1246BD065R2G Active
Pb-free
Halide free
Fixed Frequency Current Mode Controller for Flyback Converters SOIC-8 751U 1 Tape and Reel 2500 $0.5
NCP1246BD100R2G Active
Pb-free
Halide free
Fixed Frequency Current Mode Controller for Flyback Converters SOIC-8 751U 1 Tape and Reel 2500 $0.5
数据资料DataSheet下载
概述 文档编号/大小 版本
Fixed Frequency Current Mode Controller for Flyback Converters NCP1246/D (94.0kB) 2