Overview
The ULN2004AID is a high-voltage, high-current Darlington transistor array produced by Texas Instruments. This device consists of seven npn Darlington pairs, each featuring high-voltage outputs with common-cathode clamp diodes, making it suitable for switching inductive loads. Although the ULN2004AID is now obsolete and no longer in production, it remains a significant component in legacy systems and for educational purposes. The device is compatible with various types of logic, including TTL and 5-V CMOS devices, thanks to its 10.5-kΩ series base resistor for each Darlington pair.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Collector-Current Rating (Single Output) | 500 mA | mA |
| High-Voltage Outputs | 50 V | V |
| Output Clamp Diodes | Present | - |
| Input Compatibility | TTL, 5-V CMOS | - |
| Series Base Resistor | 10.5 kΩ | kΩ |
| Operating Free-Air Temperature Range | −40°C to 105°C | °C |
| Collector-Emitter Saturation Voltage (VCE(sat)) | 1.2 - 1.6 V (typical at IC = 350 mA) | V |
| Propagation Delay Time (tPLH, tPHL) | 1 - 10 µs | µs |
Key Features
- High-voltage outputs up to 50 V
- High-current capability with a single Darlington pair rated at 500 mA
- Common-cathode clamp diodes for inductive load switching
- Inputs compatible with TTL and 5-V CMOS logic
- 10.5-kΩ series base resistor for direct operation with logic devices
- Operating temperature range from −40°C to 105°C
Applications
- Relay drivers
- Hammer drivers
- Lamp drivers (including LED and gas discharge displays)
- Line drivers
- Logic buffers
Q & A
- What is the ULN2004AID?
The ULN2004AID is a high-voltage, high-current Darlington transistor array produced by Texas Instruments.
- What is the collector-current rating of a single Darlington pair in the ULN2004AID?
The collector-current rating of a single Darlington pair is 500 mA.
- What is the maximum high-voltage output of the ULN2004AID?
The maximum high-voltage output is 50 V.
- Is the ULN2004AID compatible with TTL and CMOS logic?
Yes, it is compatible with TTL and 5-V CMOS logic.
- What is the operating temperature range of the ULN2004AID?
The operating temperature range is from −40°C to 105°C.
- Can the Darlington pairs in the ULN2004AID be paralleled for higher current capability?
Yes, the Darlington pairs can be paralleled to achieve higher current capability.
- What types of loads can the ULN2004AID switch?
The ULN2004AID can switch inductive loads, such as relays and lamps.
- Is the ULN2004AID still in production?
No, the ULN2004AID is now obsolete and no longer in production.
- What are some common applications of the ULN2004AID?
Common applications include relay drivers, hammer drivers, lamp drivers, line drivers, and logic buffers.
- What is the purpose of the common-cathode clamp diodes in the ULN2004AID?
The common-cathode clamp diodes are used for switching inductive loads.
