Signal-path switch for precision analog multiplexing
The MAX319CSA+ from Analog Devices (Maxim Integrated) is a single-pole double-throw (SPDT) analog switch in an 8-SOIC package. It routes one common terminal to either of two independent signal paths, with a maximum on-state resistance of 35 Ohm and channel-to-channel matching within 2 Ohm. The switch handles rail-to-rail analog signals across a wide supply range: single 10 V to 30 V, or dual ±4.5 V to ±20 V. Typical applications include audio routing, data-acquisition front-end multiplexing, and test-equipment signal switching where the 0°C to 70°C commercial temperature grade fits lab or controlled-environment gear.
On-resistance and signal integrity
The 35 Ohm max on-resistance governs insertion loss and voltage division in the signal path. Off-leakage is rated at 250 pA max.
Switching speed and charge injection
Turn-on time is 175 ns max, turn-off 145 ns max, fast enough for audio sample rates and moderate-speed multiplexing. Charge injection is 3 pC typical — a transient glitch that couples onto the signal when the switch changes state. In high-impedance or precision-sampling circuits, this glitch can settle into the acquisition window; a downstream sample-and-hold or ADC may need a short delay after switching. The -85 dB crosstalk at 1 MHz means the off-channel leaks very little into the active path, preserving channel isolation in multi-input systems.
Supply flexibility and single-rail operation
The MAX319CSA+ accepts a single positive supply from 10 V to 30 V, or dual supplies from ±4.5 V to ±20 V.
Package and footprint
Housed in an 8-SOIC package (0.154-inch body width, 3.90 mm), the MAX319CSA+ is a surface-mount part. It ships in Tube form.
Lifecycle and compliance
The MAX319CSA+ is listed as Active on the manufacturer's lifecycle status, with ROHS3 compliance. For new designs, the part is a safe selection without near-term obsolescence risk. The commercial temperature range (0°C to 70°C) limits it to indoor, controlled-environment equipment — not suitable for automotive or extended industrial temperature without qualification.