UC2843B数据手册集成电路（IC）的PMIC-稳压器-DCDC开关式控制器规格书PDF

描述 Description

The UTC UC2843B provides off-line or DC-DC fixed-frequency current-mode control design with minimum external components. Internally-implemented circuits include an under-voltage lockout (UVLO) and a precision reference with accuracy at the error amplifier input. The UTC UC2843B also contain internal circuits which include a pulse width modulation (PWM) comparator providing current-limit control, logic ensuring latched operation, and a totem-pole output stage designed to source or sink high-peak current. The output stage is low when it is in off-state condition and suitable for N-channel MOSFETs driving. The UTC UC2843B also has following advantages: the start-up current lower than 0.5mA while the oscillator discharge current is specified to 8.3mA (Typ.). In UVLO conditions, the output has a maximum saturation voltage of 1.2V when sinking 10mA@VCC = 5V.The typical UVLO threshold of the UTC UC2843B is 8.4V (on) and 7.6V (off) and can operate to duty cycles approximately 100%.

特性 Features

•  Current mode operation:500 kHz
•  Low start-up current value<0.5mA
•  Latching PWM for cycle-by-cycle current limiting
•  Trimmed oscillator discharge current
•  Automatic feed-forward compensation
•  Internally trimmed reference with UVLO
•  High-current totem-pole output UVLO with hysteresis
• Double-pulse suppression
• Halogen free