Vishay Intertechnology has introduced an 8-channel precision analogue multiplexer, the DG1408. It combines low on-resistance of 3.2Ω with extremely low power dissipation, parasitic capacitance and charge injection.
The DG1408 is built on a new CMOS process which is characterized by low and flat resistance over the full signal range, providing excellent linearity and low signal distortion. In addition, the new multiplexer enhances the performance of gain amplifiers, offering improved circuit bandwidth and lower sensitivity to leakage.
The DG1408’s low on-resistance makes it preferable to mechanical relays, because it eliminates the relay’s mechanical bounce. A circuit based on the DG1408 is also smaller.
Parasitic capacitance is rated at 121pF, an impressive value given the device’s low switch on-resistance. The capacitance helps to create a stable amplifier circuit. Drain on-capacitance causes phase shift to the amplifier’s closed loop response, and when it is too large, the amplifier circuit may become unstable and oscillate. Low drain capacitance, together with low on-resistance, also improves the data acquisition rate and accuracy.
Benefitting from low power losses, the DG1408 draws just 17μA over the full signal range, a marked improvement on the 220μA value of the nearest competing device. Charge injection is rated at 120pC. The DG1408’s fast switching time is ideal for circuits requiring low time constants.
- Signal switching and relay replacement in data acquisition devices
- Medical equipment
- Industrial control and automation
- Sample and hold circuits
- Test and measurement equipment
- Communications equipment
- Audio-visual systems
- ±15V analogue signal range
- 35V maximum power supply
- 0.2Ω channel-to-channel on-resistance matching
- Single 4.5V to 24V power supply
- Dual ±4.5V to ±15V power supply
- Temperature range: -40°C to 125°C