LT1166 Datasheet | Linear Technology

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 bees 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 owners. TYPICAL APPLICATION MPS2907 R1 100Ω 47Ω 2N2907 1 ITOP = 15m A 5.6k VTOP SENSE+ ILIM+ 7 4.3k VIN 2 VIN LT1166 VOUT 3 ILIM- SENSE- 6 5 VBOTTOM 4 IBOTTOM = 15m A 15V R2 100Ω 300p F 1k 1µF 1µF 1k R3 100Ω MPS2222 R4 100Ω 2N2222 47Ω 300p F -...