The UC3842B, UC3843B series are high performance fixed

frequency current mode controllers. They are specifically designed for

Off−Line and DC−DC converter applications offering the designer

a cost−effective solution with minimal external components. These

integrated circuits feature a trimmed oscillator for precise duty cycle

control, a temperature compensated reference, high gain error

amplifier, current sensing comparator, and a high current totem pole

output ideally suited for driving a power MOSFET.

Also included are protective features consisting of input and

reference undervoltage lockouts each with hysteresis, cycle−by−cycle

current limiting, programmable output deadtime, and a latch for single

pulse metering.

These devices are available in an 8−pin dual−in−line and surface

mount (SOIC−8) plastic package as well as the 14−pin plastic surface

mount (SOIC−14). The SOIC−14 package has separate power and

ground pins for the totem pole output stage.

The UCX842B has UVLO thresholds of 16 V (on) and 10 V (off),

ideally suited for off−line converters. The UCX843B is tailored for

lower voltage applications having UVLO thresholds of 8.5 V (on) and 7.6 V (off).

Features

• Trimmed Oscillator for Precise Frequency Control

• Oscillator Frequency Guaranteed at 250 kHz

• Current Mode Operation to 500 kHz

• Automatic Feed Forward Compensation

• Latching PWM for Cycle−By−Cycle Current Limiting

• Internally Trimmed Reference with Undervoltage Lockout

• High Current Totem Pole Output

• Undervoltage Lockout with Hysteresis

• Low Startup and Operating Current

• This is a Pb−Free and Halide−Free Device

UC2843BD1G属于集成电路（IC） > PMIC - 稳压器 - DC DC 开关式控制器。安森美半导体公司制造生产的UC2843BD1GDC-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。