ULN2803ADWR - 8ch 50V 500mA Darlington Array | TI
MPN: ULN2803ADWR β Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.85 | $0.85 |
| 10 | $0.76 | $7.60 |
| 100 | $0.61 | $61.00 |
| 500 | $0.52 | $260.00 |
| 1,000 | $0.43 | $430.00 |
Drop-in alternatives for ULN2803ADWR β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ULN2803ADW
β Drop-Inπ Reference alternative (not in catalog)
ULN2803A
β Drop-Inπ Reference alternative (not in catalog)
ULN2803AG
β Drop-Inπ Reference alternative (not in catalog)
ULN2803ADWRG4
β Drop-Inπ Reference alternative (not in catalog)
ULN2803ADWRQ1
β Drop-Inπ Reference alternative (not in catalog)
ULN2803ADWR
β Drop-Inβ In Stock
$0.43 / Unit
View Datasheet βULN2803ADWR Maximum Ratings & Electrical Characteristics
| Number of Channels | 8 |
| Collector-Emitter Voltage (VCEO) | 50 V |
| Collector Current per Channel | 500 mA |
| Input Voltage (Logic) | TTL / 5V CMOS compatible |
| Clamp Diode | Common-cathode, connected to COM pin |
| Package | 18-SOIC (0.295", 7.50mm Width) |
| Operating Temperature Range | -40Β°C to +85Β°C |
| Power Dissipation | 1.4 W at 25Β°C ambient |
| Mounting Type | Surface Mount |
| Base Resistor | 2.7 kΞ© (typical) |
| Emitter Resistor | 3.6 kΞ© (typical) |
| Input Current (per channel) | 0.93 mA (typical at 5V input) |
| Output Leakage Current | 50 Β΅A (max at 50V) |
| RoHS Status | Compliant |
| Lifecycle Status | Last Time Buy |
ULN2803ADWR Pin Configuration
| Pin 1 | 1B β Input 1 |
| Pin 2 | 2B β Input 2 |
| Pin 3 | 3B β Input 3 |
| Pin 4 | 4B β Input 4 |
| Pin 5 | 5B β Input 5 |
| Pin 6 | 6B β Input 6 |
| Pin 7 | 7B β Input 7 |
| Pin 8 | 8B β Input 8 |
| Pin 9 | GND β Ground |
| Pin 10 | COM β Common cathode for clamp diodes |
| Pin 11 | 8C β Output 8 |
| Pin 12 | 7C β Output 7 |
| Pin 13 | 6C β Output 6 |
| Pin 14 | 5C β Output 5 |
| Pin 15 | 4C β Output 4 |
| Pin 16 | 3C β Output 3 |
| Pin 17 | 2C β Output 2 |
| Pin 18 | 1C β Output 1 |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
ULN2803ADWR is suitable for 6 applications: Relay Drivers, Stepper Motor Drivers, Solenoid Drivers, LED Display Drivers, Industrial Control, Automotive Electronics.
Relay Drivers
The ULN2803ADWR is ideal for driving relays in industrial control and automation. Each channel can sink up to 500mA, sufficient for most small relays. The integral clamp diodes suppress back-EMF when the relay coil is de-energized, protecting the transistor array. Connect the COM pin to the relay supply voltage to enable the clamp diodes. This simplifies PCB design by eliminating external flyback diodes. The TTL-compatible inputs allow direct connection to microcontrollers, reducing component count. With 8 channels, it can drive multiple relays in a compact 18-SOIC package, saving board space. The 50V rating ensures compatibility with 12V and 24V relay systems. For higher current relays, consider using two channels in parallel, but ensure the total power dissipation stays within the 1.4W limit.
Recommended
Stepper Motor Drivers
The ULN2803ADWR can drive unipolar stepper motors with up to 500mA per phase. Each of the eight channels can be used to drive one motor phase, allowing control of two stepper motors. The integral clamp diodes protect against back-EMF from the motor windings, eliminating the need for external diodes. The TTL-compatible inputs interface directly with stepper motor controller ICs or microcontrollers. The 50V rating supports common 12V and 24V stepper motors. The 18-SOIC package is compact, making it suitable for space-constrained applications like 3D printers and CNC machines. When driving stepper motors, ensure the total power dissipation across all channels does not exceed 1.4W. For higher current motors, consider using a dedicated stepper driver IC.
Recommended
Solenoid Drivers
The ULN2803ADWR is well-suited for driving solenoids in vending machines, door locks, and industrial equipment. Each channel can sink up to 500mA, sufficient for most small solenoids. The integral clamp diodes suppress back-EMF spikes when the solenoid is de-energized, protecting the transistor array. The COM pin must be connected to the solenoid supply voltage to enable the clamp diodes. The TTL-compatible inputs allow direct control from microcontrollers or PLCs. The 50V rating supports 12V and 24V solenoid systems. With 8 channels, it can drive multiple solenoids in a compact package. The 18-SOIC package is suitable for surface-mount assembly, reducing manufacturing costs. Ensure the total power dissipation stays within the 1.4W limit when multiple channels are active simultaneously.
Recommended
LED Display Drivers
The ULN2803ADWR can drive LED displays, including 7-segment and dot-matrix displays. Each channel can sink up to 500mA, allowing multiple LEDs in series or parallel. The TTL-compatible inputs interface directly with display driver ICs or microcontrollers. The 50V rating is more than sufficient for LED applications, which typically operate at 5V or 12V. The 8 channels can drive up to 8 segments or digits in a multiplexed display. The integral clamp diodes are not needed for resistive loads like LEDs but do not interfere. The 18-SOIC package is compact, making it suitable for compact display modules. When driving LEDs, use appropriate current-limiting resistors to prevent exceeding the 500mA per channel rating. The total power dissipation must be considered when many channels are active.
Recommended
Industrial Control
The ULN2803ADWR is widely used in industrial control systems for driving various loads such as relays, solenoids, and lamps. Its 8 channels provide a compact solution for multiple outputs. The TTL-compatible inputs allow direct connection to PLCs or microcontrollers. The 50V rating supports 24V industrial systems. The integral clamp diodes protect against inductive load transients, enhancing system reliability. The -40Β°C to +85Β°C operating range makes it suitable for harsh industrial environments. The 18-SOIC package is easy to assemble on PCBs. When designing, ensure adequate PCB copper for heat dissipation, especially when multiple channels are active. The Last Time Buy status requires planning for long-term availability, possibly using alternatives like the ULN2803ADW or Toshiba ULN2803AG.
Recommended
Automotive Electronics
The ULN2803ADWR can be used in automotive applications for driving relays, solenoids, and LED indicators. The 50V rating is suitable for 12V automotive systems. The TTL-compatible inputs interface with automotive microcontrollers. The integral clamp diodes protect against inductive load transients, which are common in automotive environments. The -40Β°C to +85Β°C operating range covers most automotive temperature requirements. However, for high-temperature or high-reliability applications, consider the automotive-grade ULN2803ADWRQ1 variant. The 18-SOIC package is suitable for surface-mount assembly in automotive ECUs. When designing, ensure the COM pin is connected to the battery voltage to enable clamp diodes. The Last Time Buy status may require sourcing alternatives for long-term production.
Recommended
Recommended Products Summary
Engineering reference data for ULN2803ADWR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ULN2803ADW | ULN2803AG | ULN2803ADWRG4 |
|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC |
| Brand | Texas Instruments | Texas Instruments | Toshiba | Texas Instruments |
| Collector-Emitter Voltage | 50V | 50V | 50V | 50V |
| Collector Current per Channel | 500mA | 500mA | 500mA | 500mA |
| Number of Channels | 8 | 8 | 8 | 8 |
| Input Compatibility | TTL/5V CMOS | TTL/5V CMOS | TTL/5V CMOS | TTL/5V CMOS |
| Operating Temperature | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C |
| Lifecycle Status | Last Time Buy | Active | Active | Last Time Buy |
Key Differentiators
- Integral clamp diodes (vs Discrete transistor arrays without diodes)
- TTL/5V CMOS compatible inputs (vs ULN2804A (higher input voltage))
- 8 channels in compact SOIC package (vs ULN2003 (16-pin DIP))
Design Notes
The ULN2803ADWR has a maximum power dissipation of 1.4W at 25Β°C ambient. When driving multiple channels, calculate the total power as P = V_CE(sat) * I_C per channel summed over all active channels. For example, at 500mA and 1.6V saturation voltage, each channel dissipates 0.8W, so only one channel can be fully driven at a time. Use adequate PCB copper area or a heatsink to manage thermal performance.
Place the COM pin connection to the load supply voltage close to the device to minimize loop inductance. Use a 0.1Β΅F decoupling capacitor near the VCC pin if used. For inductive loads, ensure the clamp diodes are properly connected via the COM pin to suppress back-EMF. Provide sufficient trace width for output currents up to 500mA to avoid voltage drops and overheating.
Do not exceed the absolute maximum ratings: collector-emitter voltage 50V, collector current 500mA per channel, and total power dissipation 1.4W. Ensure the COM pin is connected to the load supply voltage; otherwise, the clamp diodes are disabled, risking damage from inductive spikes. Also, avoid driving inputs above the recommended voltage range to prevent damage to the base resistors.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified; automotive variant ULN2803ADWRQ1 is available.
