The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. 74LS122 re-triggered multivibrators feature output pulse-duration control by three methods. The basic pulse time is programmed by selection of external resistance and capacitance values (see typical application data)
74LS122 Features
- DC Triggered Multivibrators with Pulse Width Control
- Overriding Clear Terminates Output Pulse
- DC Triggered from Active-High or Active-Low
- Operating Temperature up to 70°C
- Standard TTL Switching Voltages
74LS122 Specifications
| Supply Voltage | 4.75 – 5.25Vdc |
| Maximum Clock Frequency | 40Mhz |
| Power Dissipation | 2mW/gate @100kHz |
| Minimum Output Current | 8mA |
| Propagation Delay | 10nS |
| Fan Out (TTL Loads) | 20 |
74LS122 Pinout Diagram
74LS122 Pin Description
| Pin No | Pin Name | Description |
| 1 | A1 | Data Input Pin A1 |
| 2 | A2 | Data Input Pin A2 |
| 3 | B1 | Data Input Pin B1 |
| 4 | B2 | Data Input Pin B2 |
| 5 | CLR | Clear Pin |
| 6 | Q1 | Output Pin |
| 7 | GND | Ground |
| 8 | Q2 | Output Pin |
| 9 | Rint | Internal Resistor |
| 10 | NC | Not Connected |
| 11 | Cext | External Capacitor |
| 12 | NC | Not Connected |
| 13 | Rext/Cext | External Resistor/External Capacitor |
| 14 | VCC | Positive Supply |
74LS122 Circuit
Here is a simple monostable multivibrator circuit using 2n4401 transistors
Applications
- Delay and timing circuits.
74LS122 Alternative Equivalent
74LS123
Download 74LS122 Retriggerable Monostable Multivibrator Datasheet from the link given below.
