component

ULN2004A Darlington Array

Public Unreviewed

by Ray

Seven NPN Darlington pairs with 50 V, 500 mA outputs and clamp diodes, for 6-15 V CMOS inputs.

darlingtondriverrelay-drivertransistor-arraytisoic-16
Overview Files Discover Packages Releases Dependencies Issues Breadcrumbs Pull Requests Activity

3D Model

Open in new tab ↗

Symbol & Footprint

Schematic Symbol

Open full view ↗

PCB Footprint

Open full view ↗
Contents

README

markdown

ULN2004A

Texas Instruments · Transistor Array / Driver · SOIC-16

The ULN2004A is an array of seven NPN Darlington pairs with high-voltage, high-current outputs and common-cathode clamp diodes. Its input resistors are sized for 6 V to 15 V CMOS or PMOS logic (versus the 5 V TTL of the ULN2003A). Each channel sinks up to 500 mA at 50 V, driving relays, solenoids, stepper motors, and LED banks.

Pinout

Pin Name Type Function
1 1B input Channel 1 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor); accepts 6V-15V logic.
2 2B input Channel 2 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
3 3B input Channel 3 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
4 4B input Channel 4 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
5 5B input Channel 5 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
6 6B input Channel 6 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
7 7B input Channel 7 Darlington base input. CMOS/logic-level input (10.5kΩ series base resistor).
8 E power_in Common emitter shared by all seven Darlington channels. Typically tied to ground; all voltages are referenced to this terminal.
9 COM power_in Common cathode node for the seven flyback (freewheeling) clamp diodes. Required for switching inductive loads - connect to the load supply rail.
10 7C output Channel 7 Darlington open-collector output. Sinks up to 500mA at collector-emitter voltages up to 50V.
11 6C output Channel 6 Darlington open-collector output. Sinks up to 500mA at up to 50V.
12 5C output Channel 5 Darlington open-collector output. Sinks up to 500mA at up to 50V.
13 4C output Channel 4 Darlington open-collector output. Sinks up to 500mA at up to 50V.
14 3C output Channel 3 Darlington open-collector output. Sinks up to 500mA at up to 50V.
15 2C output Channel 2 Darlington open-collector output. Sinks up to 500mA at up to 50V.
16 1C output Channel 1 Darlington open-collector output. Sinks up to 500mA at up to 50V.

Key specifications

Parameter Value
Type 7-channel NPN Darlington array (sink)
Output voltage 50 V max
Output current 500 mA per channel
Input 6 V to 15 V CMOS/PMOS logic
Clamp diodes Integrated common-cathode
Operating temperature -40 C to 85 C

Ordering variants

Same part, different packaging or reel option.

  • ULN2004AD
  • ULN2004AAD
  • ULN2004AN
  • ULN2004AAN
  • ULN2004ANS
  • ULN2004AANS
  • ULN2004APW
  • ULN2004AAPW
  • ULN2004ADYY
  • ULN2004AADYY

CAD (KiCad official)

  • Symbol: uln2004a.kicad_sym
  • Footprint: uln2004a.kicad_mod
  • 3D model: SOIC-16 body from KiCad Package_SO/SOIC-16_3.9x9.9mm_P1.27mm.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (42 pp, sha256 0151daa4ffa9135f, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF