Overview
The ULQ2003AD, produced by Texas Instruments, is a high-voltage, high-current Darlington transistor array. This device is part of the ULx200xA family and is designed to interface between low-level logic circuits and high-voltage, high-current loads. The ULQ2003AD consists of seven NPN Darlington pairs, each capable of sinking up to 500 mA of current. It features a common emitter and open collector outputs, along with internal suppression diodes for inductive loads. This device is suitable for a wide range of applications, including driving solenoids, relays, lamps, small motors, and LEDs, and can operate over a temperature range of –40°C to 105°C.
Key Specifications
| Parameter | Test Conditions | Unit | Min | Max | |
|---|---|---|---|---|---|
| Input Capacitance (Ci) | VI = 0, f = 1 MHz | pF | 15 | 25 | 25 |
| ON-state Input Voltage (VI(on)) | VCE = 2 V, IC = 200 mA | V | 2.4 | 2.7 | 3 |
| Collector-Emitter Saturation Voltage (VCE(sat)) | II = 250 μA, IC = 100 mA | V | 0.9 | 1.2 | 1.4 |
| High-Level Output Voltage after Switching (VOH) | VS = 50 V, IO = 300 mA | mV | VS – 50 | VS – 50 | VS – 50 |
| Propagation Delay Time, Low- to High-Level Output (tPLH) | See Figure 6-9 | μs | 1 | 10 | 10 |
| Propagation Delay Time, High- to Low-Level Output (tPHL) | See Figure 6-9 | μs | 1 | 10 | 10 |
Key Features
- High-Current Capability: Each Darlington pair can sink up to 500 mA of current.
- Internal Suppression Diodes: For inductive loads to suppress kick-back voltage.
- Series Base Resistor: Allows operation directly with TTL or CMOS devices at supply voltages of 5 V or 3.3 V.
- Wide Temperature Range: Operates from –40°C to 105°C.
- Multiple Package Options: Available in SOIC, PDIP, SOP, TSSOP, and SOT packages.
- High Current Gain: Darlington connected NPN transistors provide a high current gain (β2) of up to 10,000 A/A.
Applications
The ULQ2003AD is commonly used in various applications requiring the interface between low-level logic circuits and high-voltage, high-current loads. These include:
- Driving Solenoids and Relays: For controlling high-current devices from low-level logic signals.
- Lamps and LEDs: For driving lighting loads that require higher current than what logic circuits can provide.
- Small Motors: For controlling the operation of small motors in various systems.
- Inductive Load Drive: The internal free-wheeling diodes make it suitable for driving inductive loads such as coils and motors.
Q & A
- What is the maximum current each Darlington pair in the ULQ2003AD can sink?
Each Darlington pair can sink up to 500 mA of current.
- What is the purpose of the internal suppression diodes in the ULQ2003AD?
The internal suppression diodes are used to suppress the kick-back voltage from inductive loads when the NPN drivers are turned off.
- Can the ULQ2003AD be used with TTL or CMOS devices?
- What is the operating temperature range of the ULQ2003AD?
The ULQ2003AD operates over a temperature range of –40°C to 105°C.
- What types of packages are available for the ULQ2003AD?
The ULQ2003AD is available in SOIC, PDIP, SOP, TSSOP, and SOT packages.
- How does the Darlington connection in the ULQ2003AD enhance its performance?
The Darlington connection provides a high current gain (β2) of up to 10,000 A/A, allowing for high-output current drive with a very low input current.
- What is the typical propagation delay time for the ULQ2003AD?
The propagation delay time (tPLH and tPHL) is typically 10 μs.
- How do you calculate the on-chip power dissipation for the ULQ2003AD?
The on-chip power dissipation can be calculated using the equation PD = Σ (VOLi * ILi), where VOLi is the output voltage for the load current ILi, and ensuring it is below the maximum allowable power dissipation dictated by the thermal resistance and ambient temperature.
- What are some common applications of the ULQ2003AD?
- How do you determine the number of coils that can be driven by the ULQ2003AD?
The number of coils can be determined based on the coil current and on-chip power dissipation, using the provided equations and figures in the datasheet.
