The LM34919C Step Down Switching Regulator features all of the functions needed to implement a low-cost, efficient, buck bias regulator capable of supplying 0.6 A to the load. This buck regulator contains an N-Channel Buck Switch and is available in DSBGA and WSON packages. The constant on-time feedback regulation scheme requires no loop compensation, results in fast load transient response, and simplifies circuit implementation. The operating frequency remains constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The valley current limit results in a smooth transition from constant voltage to constant current mode when current limit is detected, reducing the frequency and output voltage, without the use of foldback. Additional features include: Power Good, enable, VCC undervoltage lockout, thermal shutdown, gate drive undervoltage lockout, and maximum duty cycle limiter.

• AEC-Q100 qualified (Tj = –40°C to 125°C)
• Maximum Switching Frequency: 2.6 MHz
• Input Voltage Range: 4.5 V to 50 V
• Integrated N-Channel buck switch
• Integrated Start-Up Regulator
• No Loop Compensation Required
• Ultra-Fast Transient Response
• Operating Frequency Remains Constant with Load Current and Input Voltage
• Adjustable Output Voltage
• Power Good Output
• Enable Input
• Valley Current Limit at 0.64 A Typical
• Precision Internal Voltage Reference
• Low IQ Shutdown (<10 µA)
• Highly Efficient Operation
• Thermal Shutdown
• 12-Bump 2 mm × 2 mm DSBGA and 12-pin 4 mm × 4 mm WSON Packages