This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. The transistors can be replaced by the 2N2222 or 2N2218. This circuit can source currents up to 200 mA to a LED from TTL signals.
This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. The transistors can be replaced by the 2N2222 or 2N2218. This circuit can source currents up to 200 mA to a LED from TTL signals.