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 PT2209-电流模式PWM控制器 GENERAL DESCRIPTIONThe PT2209 is a highly integrated current mode PWM controller, providing low standby power and cost effective system solution for the flyback converter applications.
 The PT2209 operates at fixed 65KHz frequency. Under no load or light load conditions, PWM frequency is reduced to minimize switching loss, low standby power and high efficiency is thus achieved. The PT2209 also features low VDD startup current which also contributes to low standby power. The built in LEB on the current sense input removes the signal glitches due to snubber circuit diode reverse recovery and thus reduces the external component count and the system cost in the design. A complete set protection is implemented in the
 PT2209 including cycle-by-cycle current limiting (OCP), over load protection (OLP), VDD over voltage clamp and under voltage lockout (UVLO). The PT2209 also features latched shut down including programmable OTP and programmable OVP protection. By limiting the minimum frequency above 22 kHz, the PT2209 based system eliminates the potential audible noise when the system works under light or no load conditions. Excellent EMI performance is achieved with PowTech proprietary frequency Jittering technique together with soft driving control at totem pole gate drive output.
 The PT2209 is available in an SOT23-6 package.
 FEATURES Frequency jittering for improved EMI
  Green-Mode PWM for improved efficiency and minimum standby power design
  Fixed 65KHz PWM frequency
  Built in 4mS soft start
  Low start up current 20uA ( Typ. 3uA) and low operation current (Typ. 1.8mA)
  Current mode operation
  Leading-edge blanking on current sense input
  Constant output power limit for universal AC input
  Built-in power limit control (OLP)
  Cycle-by-cycle current limiting (OCP)
  Under voltage lockout (UVLO)
  Latched programmable OTP
  Latched programmable OVP
 
 APPLICATIONSOffline AC/DC flyback converters for
  Power Adapter
  Open-frame SMPS
  Battery Charger Adapter
  HB LED lighting.
 PT2209变压器计算表下载>>>    
 
| 产品型号 | 产品类型 | 功率范围 | 待机功耗 | Operating Junction Temp.(°C) | 产品特征描述 |  
| PT2209 | 电流模式PWM控制器 | <=50W | <100mW | -40 to +150 | 满足能源5级标准,低成本,PWM反激式控制器,支持 OCP, OLP, UVLO ,OTP 和 OVP. |        
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