摘要 |
A laser diode driver circuit uses transconductance amplifying devices, preferably FETs, in a balanced input configuration. First and second amplifying devices are arranged to receive respective inverting and non-inverting input signals on their respective control terminals (gates). The amplifying devices are arranged to drive a laser diode connected between the current output terminals (source terminals) of said first and second amplifying devices. In one embodiment, a first node connects a source terminal of a first amplifier FET, a first terminal of the laser diode, and a drain terminal of a biasing FET. In another embodiment, in addition to the circuitry of the first embodiment a second node connects the second amplifier FET, a drain of a second biasing FET, and a second terminal of the laser diode. Preferably, the first and (optionally) the second biasing FETs bias the circuit's outputs with an offset, relative to one another, of substantially the turn-on threshold of the laser diode. The invention provides fast transitions with low power consumption.
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