Overview
Description
The QS3251 is a high-speed CMOS TTL-compatible 8:1 multiplexer/demultiplexer that has 3-state outputs. The QS3251 is a function and pinout-compatible version of the 74F251, 74FCT251, and the 74ALS/AS/LS251 8:1 multiplexers. The low ON-resistance of the QS3251 allows inputs to be connected to outputs without adding propagation delay and without generating additional ground bounce noise. Mux/Demux devices provide an order of magnitude faster speed than equivalent logic devices. The QS3251 is characterized for operation at -40 °C to +85 °C.
Features
- Enhanced N-channel FET with no inherent diode to VCC
- 5Ω bidirectional switches connect inputs to outputs
- Zero propagation delay, zero ground bounce
- Undershoot clamp diodes on all switch and control inputs
- TTL-compatible control inputs
- Available in 16-pin QSOP and S1 packages
Comparison
Applications
- Logic replacement
- Video, audio, graphics switching, muxing
- Hot-swapping, hot-docking
- Voltage translation (5V to 3.3V)
Design & Development
Models
ECAD Models
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.