Overview
The L293B, produced by STMicroelectronics, is a quad push-pull driver capable of delivering output currents up to 1A per channel. This device is designed to accept standard TTL-compatible logic levels and drive inductive loads such as DC motors, relays, and solenoids. The L293B is packaged in a 16-pin plastic DIP and features a separate logic supply input, allowing it to run off a lower voltage to reduce power dissipation. Additionally, it includes an inhibit facility that can turn off all four transistors, and it uses the four center pins to conduct heat to the printed circuit board.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (Vs) | 4.5 to 36 | V |
| Logic Supply Voltage (Vss) | 4.5 to 36 | V |
| Input Voltage (Vi) | -0.3 to 7 | V |
| Inhibit Voltage (Vinh) | -0.3 to 7 | V |
| Output Current per Channel | 1 | A |
| Peak Output Current per Channel (non-repetitive) | 2 | A |
| Total Power Dissipation at Tground-pins = 80°C | 5 | W |
| Storage and Junction Temperature | -40 to +150 | °C |
| Thermal Resistance Junction-case (Rth j-case) | 14 | °C/W |
| Thermal Resistance Junction-ambient (Rth j-amb) | 80 | °C/W |
Key Features
- Output Current: Up to 1A per channel, with a peak output current of 2A per channel (non-repetitive).
- Inhibit Facility: Each pair of drivers has an inhibit input that can turn off all four transistors.
- Separate Logic Supply: Allows the logic to run off a lower voltage to reduce power dissipation.
- High Noise Immunity: Designed to operate in noisy environments.
- Overtemperature Protection: Built-in protection against overheating.
- Heat Dissipation: Uses the four center pins to conduct heat to the printed circuit board.
Applications
- DC Motor Control: Suitable for controlling DC motors, including bidirectional control and fast motor stop.
- Stepping Motor Control: Can be used for bipolar stepping motor control with phase current control and short circuit protection.
- Relay and Solenoid Control: Capable of driving relays and solenoids.
- General Purpose Driving: Can drive other inductive loads such as valves and actuators.
Q & A
- What is the maximum output current per channel of the L293B?
The maximum output current per channel is 1A, with a peak output current of 2A (non-repetitive).
- What is the inhibit facility in the L293B?
The inhibit facility allows turning off all four transistors using an inhibit input.
- Can the L293B be used with different logic supply voltages?
Yes, the L293B has a separate logic supply input that can run off a lower voltage to reduce power dissipation.
- How does the L293B handle heat dissipation?
The L293B uses the four center pins to conduct heat to the printed circuit board.
- What are the typical applications of the L293B?
The L293B is typically used for DC motor control, stepping motor control, and driving relays and solenoids.
- What is the operating temperature range of the L293B?
The operating temperature range is from -40°C to +150°C for storage and junction temperature.
- Does the L293B have overtemperature protection?
Yes, the L293B has built-in overtemperature protection.
- What is the thermal resistance of the L293B?
The thermal resistance junction-case (Rth j-case) is 14°C/W, and junction-ambient (Rth j-amb) is 80°C/W.
- Can the L293B be used in noisy environments?
Yes, the L293B is designed to have high noise immunity.
- What package types are available for the L293B?
The L293B is packaged in a 16-pin plastic DIP.
