ULN2802A STMicroelectronics Transistor Arrays (DIP-18) In Stock
ULN2802A is an 8-channel Darlington transistor array peripheral driver IC by STMicroelectronics with open-collector outputs and built-in transient suppression diodes. Key specs: 8 outputs, open-collector sink configuration, 18-pin DIP package. From $0.60, in stock with worldwide shipping.
- Manufacturer
- STMicroelectronics
- Package
- DIP-18
- Pin Count
- 18
- Lifecycle
- ACTIVE
- Datasheet
- ULN2802A Datasheet PDF
- Category
- Transistor Arrays
- Price
- From $1.5062(MOQ 5)
- Temp Range
- -20.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 8 independent Darlington transistor pairs in a single 18-pin DIP package replace 8 discrete NPN transistor stages for relay, solenoid, and stepper motor driving
- Open-collector output configuration with built-in transient suppression diodes protects against inductive flyback from relay coils and solenoids without external clamping diodes
- High current sink capability per channel enables direct drive of 5 V, 12 V, and 24 V relay coils and indicator lamps from low-current microcontroller I/O pins
Applications
ULN2802A is a standard interface IC for driving inductive loads such as relay coils, solenoid valves, and stepper motor windings from microcontroller or PLC output pins. Its 8-channel Darlington array allows a single IC to control an 8-output relay board or a 4-phase unipolar stepper motor, covering a wide range of industrial and consumer automation applications. The integrated suppression diodes eliminate the need for external flyback diodes on each output channel, simplifying PCB layout and reducing component count.
Specifications
| Factory Lead Time | 10Weeks |
| YTEOL | 5.5 |
| Built-in Protections | TRANSIENT |
| Driver Number of Bits | 8 |
| Interface IC Type | BUFFER OR INVERTER BASED PERIPHERAL DRIVER |
| JESD-30 Code | R-PDIP-T18 |
| Number of Functions | 1 |
| Output Characteristics | OPEN-COLLECTOR |
| Output Current Flow Direction | SINK |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | DIP18,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Surface Mount | NO |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Turn-off Time | 1 µs |
| Turn-on Time | 1 µs |
| ## ULN2802A Alternates Showing results | Image |
| Package | DIP-18 |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
| Country of Origin | Mainland China, Malaysia |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for ULN2802A:
suggested
suggested
suggested
Frequently Asked Questions
How many output channels does ULN2802A provide and what type of load can each channel drive?
ULN2802A provides 8 independent open-collector Darlington output channels. Each channel can sink sufficient current to drive relay coils operating at 5 V, 12 V, or 24 V, solenoids, LED indicator arrays, and lamp loads. The built-in transient suppression diodes on each output allow direct connection to inductive loads without external clamping circuitry.
Why are the built-in transient suppression diodes in ULN2802A important when driving relay coils from a microcontroller?
When a relay coil is de-energized, its stored magnetic energy generates a voltage spike that can reach several hundred volts in microseconds. Without clamping, this spike can destroy the output transistors and damage nearby ICs. ULN2802A integrates transient suppression diodes on all 8 outputs, clamping inductive kickback voltages to safe levels and protecting the driving microcontroller's I/O pins from damage.
Can ULN2802A be used to drive a 4-phase unipolar stepper motor and what supply voltage is needed for the motor coils?
Yes, ULN2802A can drive a 4-phase unipolar stepper motor using 4 of its 8 output channels, one per coil winding. The motor coil supply voltage should match the stepper's rated voltage, typically 5 V to 24 V, connected to the COM pin while the 8 channel outputs sink current through each winding. A typical 12 V, 200-step-per-revolution stepper with 50 mA to 200 mA coil current is well within ULN2802A's output rating.
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About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 5+ | $2.7700 | $13.85 |
| 10+ | $2.1000 | $21.00 |
| 25+ | $1.7703 | $44.26 |
| 100+ | $1.5399 | $153.99 |
| 260+ | $1.5364 | $399.46 |
| 500+ | $1.5062 | $753.10 |
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