Based on Texas Instruments documentation, this circuit is based on the BQ2000 a circuit used to power LEDs. The circuit can be used with lithium-ion batteries.
This useful inductance bridge was found in a Radio Electronics from September 1963. The...
This circuit is a handset receiver that picks up the signal emitted by a coil under the rug or...
This circuit found in the October 1975 issue of Radio Electronics magazine uses an integrated...