LM34925MR/NOPB

The LM34925 regulator integrates all the features needed to implement a low-cost, high-efficiency isolated bias regulator. This high-voltage regulator contains two 100V N-channel MOSFET switches: a high-side buck switch and a low-side synchronous switch. The constant on-time (COT) control scheme eliminates the need for loop compensation and delivers excellent transient response. The on-time of this regulator is inversely proportional to the input voltage, a characteristic that keeps the operating frequency relatively constant. An integrated sensing circuit performs intelligent peak current limiting. Additional features include a programmable input undervoltage comparator to inhibit operation under low-voltage conditions. Protection features include thermal shutdown and VCC undervoltage lockout (UVLO). The LM34925 device is available in an 8-pin WSON and an 8-pin SO PowerPAD plastic package.

Applications

• Isolated telecom bias power supply
• Isolated automotive and industrial electronic components

Key features

• Wide input voltage range: 7.5V to 100V
• Integrated 100mA high-side and low-side switches
• No Schottky diode required
• Constant on-time control
• No loop compensation required
• Ultra-fast transient response
• Near-constant operating frequency
• Intelligent peak current limiting
• Adjustable output voltage (1.225V reference voltage)
• 2% feedback reference voltage accuracy
• Frequency adjustable up to 1MHz
• Adjustable UVLO
• Remote shutdown
• Thermal shutdown
• Package: 8-pin WSON, 8-pin SO PowerPAD