9: GND (the IC's own ground/substrate return — separate from COM)
10: COM (common flyback-diode cathode — tie to the driven loads' own supply+ for inductive loads; leave unconnected for purely resistive loads like LEDs)
11–18: OUT8–OUT1 (open-collector outputs, inverted relative to their input, each sinking up to ~500mA)
500 mA max per channel (total limited by package dissipation)
Saturation voltage
≈ 0.9 V at 100 mA, 1.1 V at 200 mA, 1.3 V at 350 mA (typ)
इनपुट
2.7 kΩ series resistor built in; driven directly from 5 V TTL/CMOS
Flyback diodes
Built in, common cathode on COM (pin 10)
पैकेज
DIP-18, SOIC-18
नोट्स
The 8-channel version of the ULN2003 module above, in a bare DIP-18 — same idea (Darlington pairs driving relays/motors/solenoids straight from logic-level inputs), one more channel, no board attached.
A quick wiring check once populated: IN1(pin1) sits directly opposite OUT1(pin18) across the package, IN8(pin8) opposite OUT8(pin11), and GND(9) opposite COM(10) — the pin numbering folds symmetrically around the package.
