LT1166

LT1166 Power Output Stage Automatic Bias System FEATURES nn Set Class AB Bias Currents nn Eliminates Adjustments nn Eliminates Thermal Runaway of IQ nn Corrects for Device Mismatch nn Simplifies Heat Sinking nn Programmable Current Limit nn May Be Paralleled for Higher Current nn Small SO-8 or PDIP Package APPLICATIONS nn Biasing Power MOSFETs nn High Voltage Amplifiers nn Shaker Table Amplifiers nn Audio Power Amplifiers DESCRIPTION The LT®1166 is a bias generating system for controlling class AB output current in high powered amplifiers. When connected with external transistors, the circuit becomes a unity-gain voltage follower. The LT1166 is ideally suited for driving power MOSFET devices because it eliminates all quiescent current adjustments and critical transistor matching. Multiple output stages using the LT1166 can be paralleled to obtain higher output current. Thermal runaway of the quiescent point is eliminated because the bias system senses the current in each power transistor by using a small external sense resistor. A high speed regulator loop controls the amount of drive applied to each power device. The LT1166 can be biased from a pair of resistors or current sources and because it operates on the drive voltage to the output transistors, it operates on any supply voltage. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and C-Load is a trademark of Analog Devices, Inc. All other trademarks are the property of their respective o...