LM34927SD/NOPB

The LM34927 regulator features all of the functions needed to implement a low-cost, efficient, isolated bias regulator. This high-voltage regulator contains two 100-V N-channel MOSFET switches — a highside buck switch and a low-side synchronous switch. The Constant on-time (COT) control scheme employed in the LM34927 device requires no loop compensation and provides excellent transient response. The regulator operates with an on-time that is inversely proportional to the input voltage. This feature allows the operating frequency to remain relatively constant. An intelligent peak current limit is implemented with integrated sense circuit. Other features include a programmable input undervoltage comparator to inhibit operation during low-voltage conditions. Protection features include thermal shutdown and VCC undervoltage lockout (UVLO). The LM34927 device is offered in WSON-8 and SO PowerPAD-8 plastic packages.

Applications

• Isolated telecom bias supply
• Isolated automotive and industrial electronics

Key features

• Wide 7.5-V to 100-V Input Range
• Integrated 600-mA High-Side and Low-Side Switches
• No Schottky Required
• Constant On-Time Control
• No Loop Compensation Required
• Ultra-Fast Transient Response
• Nearly Constant Operating Frequency
• Intelligent Peak Current Limit
• Adjustable Output Voltage From 1.225 V
• Precision 2% Feedback Reference
• Frequency Adjustable to 1 MHz
• Adjustable Undervoltage Lockout (UVLO)
• Remote Shutdown
• Thermal Shutdown
• Packages:
• 8-pin WSON
• 8-pin SO PowerPAD