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PubMed · 1787740

A linearized DC lamp controller.

J A Galbraith
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Abstract

The design of a simple and inexpensive battery powered lamp controller for microscope lamps commonly used in patch clamp and other biophysical studies is described. The circuit linearizes the normally exponential voltage-intensity curve of standard 12-V lamps by using an operational amplifier to provide feedback to the drain of a power MOSFET. When the unit is turned off, a charging circuit recharges the battery at a constant potential until the battery voltage reaches a preset level. The charging voltage is then reduced to balance the self-discharge rate of the battery.

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J A Galbraith. 1991. A linearized DC lamp controller.. https://doi.org/10.1016/0165-0270(91)90098-k

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