UC3844D集成电路（IC）的DC-DC开关控制器规格书PDF中文资料

UC3844D属于集成电路（IC）的DC-DC开关控制器。由德州仪器制造生产的UC3844DDC-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。

1 Features

• Optimized for off-line and DC-to-DC converters

• Low start-up current (< 1mA)

• Automatic feedforward compensation

• Pulse-by-pulse current limiting

• Enhanced load-response characteristics

• Undervoltage lockout with hysteresis

• Double-pulse suppression

• High-current totem-pole output

• Internally trimmed bandgap reference

• Up to 500kHz operation

• Error amplifier with low output resistance

2 Applications

• Switching regulators of any polarity

• Transformer-coupled DC-DC converters

3 Description

The UCx84x series of control integrated circuits

provide the features that are necessary to implement

off-line or DC-to-DC fixed-frequency current-mode

control schemes, with a minimum number of external

components. The internally implemented circuits

include an undervoltage lockout (UVLO), featuring a

start-up current of less than 1mA, and a precision

reference trimmed for accuracy at the error amplifier

input. Other internal circuits include logic to provide

latched operation, a pulse-width modulation (PWM)

comparator that also provides current-limit control,

and a totem-pole output stage that is designed to

source or sink high-peak current. The output stage,

designed for driving N-channel MOSFETs, is low

when the output stage is in the off state.

The UCx84x family offers a variety of package

options, temperature range options, choice of

maximum duty cycle, and choice of turnon and turnoff

thresholds and hysteresis ranges. Devices with higher

turnon or turnoff hysteresis are good choices for

off-line power supplies, while the devices with a

narrower hysteresis range are designed for DC-DC

applications. The UC184x devices are specified for

operation from –55°C to 125°C, the UC284x series is

specified for operation from –40°C to 85°C, and the

UC384x series is specified for operation from 0°C to

70°C.