4170Vrms isolation in a 6-DIP through-hole package
The onsemi 4N35VM is a single-channel optocoupler that provides 4170Vrms galvanic isolation between a DC input LED and a phototransistor output with base access. That isolation rating covers basic insulation for mains-referenced circuits in industrial controls, PLC digital inputs, and motor-drive feedback paths. The transistor with base output gives the designer the option to bias the base for faster switching or to configure a Darlington pair for higher gain — the 2µs typical turn-on and turn-off time suits 24V DC logic interfaces at moderate data rates.
The 100% current transfer ratio minimum at If=10mA guarantees that the output transistor can sink at least 10mA collector current when the LED is driven at 10mA. For a 5V logic input with a 2.2kΩ pull-up, that translates to about 2.3mA collector current — well within the CTR margin even at the low end of the operating temperature range. Maximum Vce saturation of 300mV at the rated forward current keeps the output voltage drop low enough to guarantee a logic-low level below 0.8V for TTL-compatible inputs. If the downstream receiver has a lower VIL threshold, the 300mV ceiling still leaves headroom.
Standard lead times apply through authorized distribution; the ROHS3 compliance means no exemption-based paperwork for EU-market builds. The 6-DIP (0.300-inch, 7.62mm) through-hole package is a mature form factor — no moisture sensitivity level (MSL) concerns, no bake-out required before assembly.