Darlington gain margin — why the CTR range matters
The HCPL0701V guarantees a current transfer ratio between 500% and 2600% at a forward current of just 1.6 mA. At the minimum end, 500% means a 1.6 mA LED drive yields 8 mA at the output — enough to saturate a TTL or CMOS gate input. At the maximum end, 2600% delivers 41.6 mA, which directly drives a small relay or a PLC input module without an external transistor stage. The 2500 Vrms isolation rating per IEC 60747-5-5 qualifies it for reinforced insulation in industrial bus isolators, motor-drive feedback paths, and medical equipment where the patient-accessible circuit must be galvanically separated from the mains side.
Switching speed — the asymmetry to budget for
Turn-on time is 300 ns typical, but turn-off stretches to 1.6 µs. That 5:1 ratio means the output falls slower than it rises — the useful pulse-width modulation frequency tops out around 300 kHz before the off-time compresses the duty cycle. For a 100 kHz signal the output still resolves cleanly; above 500 kHz the falling edge bleeds into the next cycle. The Darlington output stage saturates at roughly 1 V collector-emitter at 60 mA, leaving a 17 V swing into an 18 V load. The 60 mA continuous output per channel is the DC limit; pulsed loads at low duty cycle can exceed this, but the junction temperature rise in the 8-SOIC package sets the practical ceiling.
Package and temperature grade
Housed in the standard 8-SOIC wide-body (0.154-inch width, 3.90 mm), the footprint matches the industry-standard SOIC-8 land pattern. Supplied in tube packaging — not tape-and-reel. For automated pick-and-place, a tube-to-reel transfer is needed unless the line feeds from tubes directly. ROHS3 compliant with no exemption conflicts for EU or California market shipments.