logic

ULN2003

Every spec below is cited to the manufacturer datasheet. Pick your exact ordering code, compare the closest alternatives, then ask the assistant what it means for your design.

00 — Overview

What the ULN2003 family does

The ULN2001, ULN2002, ULN2003, and ULN2004 are high voltage, high current Darlington arrays containing seven open collector pairs with common emitters. Each channel handles 500 mA continuous current and withstands 600 mA peak currents. These devices feature integrated suppression diodes for inductive loads and support input voltages from 4.5 V to 25 V depending on the specific variant. They interface with TTL, CMOS, PMOS, and DTL logic families. Engineers typically use them to drive solenoids, relays, DC motors, LED displays, filament lamps, and thermal printheads. Available in 16-pin plastic DIP and SO-16 narrow packages, the outputs can also be paralleled for higher current requirements.

Next step
Start building with ULN2003 → Every number above is cited straight from the datasheet — ask what they mean for your design, and the assistant answers from the same source documents.
Ordering code:
01 — Key specifications

ULN2003 datasheet parameters

ParameterMinTypMaxConditionsSource
output voltage (abs max) — — 50 V vo; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output current (abs max) — — 500 mA ic; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
operating temperature (abs max) -40 °C — 85 °C ta; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
input capacitance — 15 pF 25 pF ci; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
propagation delay — 250 ns 1 µs 0.5 VIto 0.5 VO; tphl; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
output voltage low — 900 mV — IC = 100 mA, IB = 250 µA ST datasheet, p. 6 — Table 3. Electrical characteristics
01 — Key specifications

ULN2001 datasheet parameters

ParameterMinTypMaxConditionsSource
output voltage (abs max) — — 50 V vo; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output current (abs max) — — 500 mA ic; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
forward voltage — 1.7 V 2 V IF = 350 mA; vf(figure 10.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
operating temperature (abs max) -40 °C — 85 °C ta; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
input bias current (abs max) — — 25 mA ib; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
reverse leakage current — — 50 µA VR = 50 V; ir(figure 9.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
input capacitance — 15 pF 25 pF ci; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
propagation delay — 250 ns 1 µs 0.5 VIto 0.5 VO; tphl; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
output voltage high (abs max) — — 50 V ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output voltage low — 900 mV — IC = 100 mA, IB = 250 µA ST datasheet, p. 6 — Table 3. Electrical characteristics
01 — Key specifications

ULN2002 datasheet parameters

ParameterMinTypMaxConditionsSource
output voltage (abs max) — — 50 V vo; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output current (abs max) — — 500 mA ic; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
forward voltage — 1.7 V 2 V IF = 350 mA; vf(figure 10.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
operating temperature (abs max) -40 °C — 85 °C ta; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
input bias current (abs max) — — 25 mA ib; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
reverse leakage current — — 50 µA VR = 50 V; ir(figure 9.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
input capacitance — 15 pF 25 pF ci; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
propagation delay — 250 ns 1 µs 0.5 VIto 0.5 VO; tphl; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
output voltage high (abs max) — — 50 V ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output voltage low — 900 mV — IC = 100 mA, IB = 250 µA ST datasheet, p. 6 — Table 3. Electrical characteristics
01 — Key specifications

ULN2004 datasheet parameters

ParameterMinTypMaxConditionsSource
output voltage (abs max) — — 50 V vo; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output current (abs max) — — 500 mA ic; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
forward voltage — 1.7 V 2 V IF = 350 mA; vf(figure 10.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
operating temperature (abs max) -40 °C — 85 °C ta; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
input bias current (abs max) — — 25 mA ib; Absolute maximum ratings ST datasheet, p. 5 — Table 1. Absolute maximum ratings
reverse leakage current — — 50 µA VR = 50 V; ir(figure 9.); Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
input capacitance — 15 pF 25 pF ci; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
propagation delay — 250 ns 1 µs 0.5 VIto 0.5 VO; tphl; Electrical characteristics ST datasheet, p. 6 — Table 3. Electrical characteristics
output voltage high (abs max) — — 50 V ST datasheet, p. 5 — Table 1. Absolute maximum ratings
output voltage low — 900 mV — IC = 100 mA, IB = 250 µA ST datasheet, p. 6 — Table 3. Electrical characteristics
03 — Alternatives

Closest matches to ULN2003

MC74HC165A 9.0× lower output voltage low, 1.6× higher operating temperature, 1.5× lower input capacitance
SN54HC14 20.0× lower output current, 9.0× lower output voltage low, 4.5× lower propagation delay
ATF16V8B 1.8× lower output voltage low, similar operating temperature
SN54HC595 14.3× lower output current, 9.0× lower output voltage low, 1.6× higher operating temperature
HT12D 11.1× lower output voltage high, 1.8× lower output voltage low, 1.2× higher operating temperature
74LVC245A 18.2× lower output voltage, 10.0× lower output current, 4.5× lower output voltage low
74LVC2G14GM 18.2× lower output voltage, 10.0× lower output current, 9.0× lower output voltage low
NC7WZ16 15.4× lower output voltage, 9.0× lower output voltage low, 6.0× lower input capacitance
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