电流模式PWM控制器 Current Mode PWM Controller
DESCRIPON
The UC1842/3/4/5 family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include under-voltage lockout featuring start up current less than 1mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched
operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N Channel MOSFETs, is low in the off state.
FEATURES
• Optimized For Off-line And DC To DC Converters
• Low Start Up Current <1mA
• Automatic Feed Forward Compensation
• Pulse-by-pulse Current Limiting
• Enhanced Load Response Characteristics
• Under-voltage Lockout With Hysteresis
• Double Pulse Suppression
• High Current Totem Pole Output
• Internally Trimmed Bandgap Reference
• 500khz Operation
• Low ROError Amp