Linear Technology Corp. (LTC, Milpitas, CA) introduced its new LT3800, a current-mode, high-voltage, step-down controller with line and load regulation, along with fast transient response that operates without requiring an auxiliary dc-dc regulator for startup. The LT3800 has applications in 12 V and 42 V automotive, 48 V telecom supplies, avionic and industrial control systems.
The LT3800 operates from 4 V to 60 V supplies and regulates output voltages ranging from 1.23 V to 36 V at load currents up to 10 A. By driving n-channel MOSFETs synchronously with maximum gate-source "ON" voltage, this controller operates at 94% efficiency while converting 60 V input to 12 V at 36 W output. Moreover, the LT3800 incorporates Burst-Mode® operation, which reduces no-load quiescent current to less than 100 µA, a feature required in automotive maintenance power supplies. The LT3800 operates at a 200 kHz fixed frequency. The device employs a reverse-current inhibit feature to increase efficiency during light loads.
The LT3800 is offered in a 16-pin, thermally enhanced TSSOP, and is rated for operation from -40 ° to +125 °C. Pricing for 1,000-piece quantities starts at $3.10.
