UC2825A-Q1

www.ti.com HIGH-SPEED PWM CONTROLLER UC2825A-Q1 SLUS781 – SEPTEMBER 2007 FEATURES 1 Qualified for Automotive Applications Improved Version of the UC3825 PWM Compatible With Voltage-Mode or Current-Mode Control Methods Practical Operation at Switching Frequencies to 1 MHz 50-ns Propagation Delay to Output High-Current Dual Totem-Pole Outputs: 2 A (Peak) Trimmed Oscillator Discharge Current Low 100-μA Startup Current Pulse-by-Pulse Current-Limiting Comparator Latched Overcurrent Comparator With Full-Cycle Restart DESCRIPTION The UC2825A pulse-width modulation (PWM) controller is an improved versions of the standard UC3825. Performance enhancements have been made to several of the circuit blocks. Error amplifier gain bandwidth product is 12 MHz, while input offset voltage is 2 mV. Current limit threshold is specified to a tolerance of 5%. Oscillator discharge current is specified at 10 mA for accurate dead-time control. Frequency accuracy is improved to 6%. Startup supply current, typically 100 μA, is ideal for off-line applications. The output drivers are redesigned to actively sink current during undervoltage lockout (UVLO) at no expense to the startup current specification. In addition, each output is capable of 2-A peak currents during transitions. BLOCK DIAGRAM 1 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto ap...