TL494中文资料PWM控制器（频率可达200kHz）数据手册ONSEMI规格书

描述 Description

The TL494 PWM Controller incorporates all the functions required in the construction of a pulse width modulation (PWM) control circuit on a single chip. Designed primarily for power-supply control, this device offers the flexibility to tailor the power-supply control circuitry to a specific application. The TL494 PWM Controller contains two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, a 5-V, 5%-precision regulator, and output-control circuits.The error amplifiers exhibit a common-mode voltage range from -0.3 V to VCC -2 V. The dead-time control comparator has a fixed offset that provides approximately 5% dead time. The on-chip oscillator can be bypassed by terminating RT to the reference output and providing a sawtooth input to CT, or it can drive the common circuits in synchronous multiple-rail power supplies.The uncommitted output transistors provide either common-emitter or emitter-follower output capability. This PWM Controller provides for push-pull or single-ended output operation, which can be selected through the output-control function. The architecture of this device prohibits the possibility of either output being pulsed twice during push-pull operation.The TL494C PWM Controller is characterized for operation from 0C to 70C. The TL494I is characterized for operation from -40C to 85C. The TL494B is characterized for operation from -40C to 125C. The NCV494B is characterized for -40C to 125C and certified for automotive applications.

特性 Features

• Variable Frequency Operation (up to 200 KHz)
• Optimize system size and efficiency
• PWM Buck Controller Configuration
• Simple to use in buck configuration
• Complete Pulse Width Modulation Control Circuitry
• On-Chip Oscillator with Master or Slave Operation
• On-Chip Error Amplifiers
• On-Chip 5.0 V Reference
• Adjustable Deadtime Control
• Uncommitted Output Transistors Rated to 500 mA Source or Sink
• Output Control for Push-Pull or Single-Ended Operation
• Undervoltage Lockout
• Pb-Free Packages are Available*

应用 Application

• Off-line power supply
• Buck converter
• VPA (Vehicle Power Adapter)
• LED Lighting

简介

TL494属于集成电路（IC）的PMIC-稳压器-DCDC开关式控制器。由制造生产的TL494DC-DC 开关控制器PMIC（电源管理集成电路）DC 到 DC 开关式控制器是用于高效率电路的稳压 IC，其配置为生成高于（突升或步升）或低于（突降或步降）输入电源的输出电源电压。其他拓扑结构可能包括：降压-升压、反激、正激、Cuk、SEPIC、全桥、半桥和推挽式。这些器件不同于需要最小电压并“烧尽”多余电压的线性稳压器。