The LM1972 is a digitally controlled 2-channel 78dB audio attenuator fabricated on a CMOS process. Each channel has attenuation steps of 0.5dB from 0dB–47.5dB, 1.0dB steps from 48dB–78dB, with a mute function attenuating 104dB. Its logarithmic attenuation curve can be customized through software to fit the desired application. The performance of a µPot is demonstrated through its excellent Signal-to-Noise Ratio, extremely low (THD+N), and high channel separation. Each µPot contains a mute function that disconnects the input signal from the output, providing a minimum attenuation of 96dB.
LM1972 Pinout
LM1972 Pin Configuration
| Pin No | Pin Name | Description |
|---|---|---|
| 1 | GND AC | Ground AC Pin |
| 2 | OUT 1 | Output Pin 1 |
| 3 | GND 1 | Ground Pin 1 |
| 4 | IN 1 | Input Pin 1 |
| 5 | GND AC | Ground AC Pin |
| 6 | GND AC | Ground AC Pin |
| 7 | VSS 2 | source supply 2 |
| 8 | LOGIC GND | Logic Ground Pin |
| 9 | CLK | Clock Signal Pin |
| 10 | LOAD/SHIFT | Load /Shift Pin |
| 11 | DATA-IN | Data Input Pin |
| 12 | DATA-OUT | Data Output Pin |
| 13 | VDD 1 | Drain supply 1 |
| 14 | GND AC | Ground AC Pin |
| 15 | VDD 2 | Drain supply 2 |
| 16 | GND AC | Ground AC Pin |
| 17 | OUT 2 | Output Pin 2 |
| 18 | VSS 1 | source supply 1 |
| 19 | GND 2 | Ground Pin 2 |
| 20 | IN 2 | Input Pin 2 |
LM1972 Specification & Features
- Frequency response: 100 kHz (−3dB) (min)
- Attenuation range (excluding mute): 78dB (typ)
- Differential attenuation: ±0.25dB (max)
- Signal-to-noise ratio (ref. 4 Vrms): 110dB (min)
- Channel separation: 100dB (min)
- 3-wire serial interface
- Daisy-chain capability
- 104dB mute attenuation
- Pop and click free attenuation changes
Application
- Automated studio mixing consoles
- Music reproduction systems
- Sound reinforcement systems
- Electronic music (MIDI)
- Personal computer audio control
You can download this datasheet for LM1972 2-Channel Audio Attenuator – Datasheet from the link given below:
