The ACPL-M50L (single-channel) is a low power, low-input current, high speed digital optocoupler in SO-5 footprint. This digital optocoupler use an insulating layer between the light emitting diode and an integrated photon detector to provide electrical insulation between input and output. Separate connections for the photodiode bias and output transistor collector increase the speed up to a hundred times over that of a conventional photo-transistor coupler by reducing the base collector capacitance. The ACPL-M50L have an increased common mode transient immunity of 15kV/µs minimum at VCM=1500V over a temperature range of -40 to 105°C. The current transfer ratio (CTR) is 120% typical at IF=3mA. This digital optocoupler can be used in any TTL/CMOS, TTL/LSTTL or wide bandwidth analog applications.