UC3845D

illustrate

The UC1842/3/4/5 family provides the necessary functions to implement a fixed frequency current mode control scheme with minimal external component count off-wire or DC-to-DC fixed frequency current mode. Internal implementation circuitry includes undervoltage lockout with a start-up current of less than 1 mA, an accurate reference accuracy trim at the input of the error amplifier, logic registration to ensure lockout operation, PWM comparators that provide current limit control while providing current limit, and a totem pole output to stage the design of high peak currents for sources or sinks. Output stage, driving N-channel MOSFETs suitable for low off.

The difference between this family member is the undervoltage lockout threshold and the maximum duty cycle range.

characteristic

• Optimize offline and DC-DC converters
• Low start-up current" (
• Automatic Forward Compensation
• The pulse is limited by the pulse current
• Enhanced load response characteristics
• Undervoltage lockout
• Double pulse suppression
• The totem pole outputs a large current
• Internal fine-tuning bandgap reference
• 500 - kHz operation
• Low R_OError amplifier