Quad SPST-NO analog switch for precision signal routing
The Maxim Integrated MAX327CSE+T is a quad single-pole single-throw normally-open analog switch in a 16-SOIC surface-mount package. Each of the four independent switches handles analog or digital signals with a maximum on-resistance of 3.5 kOhm and channel-to-channel matching of 175 Ohm. The switch operates from dual supplies of ±5V to ±18V or a single supply of 10V to 30V, making it flexible for split-rail or single-rail analog front-ends. Typical applications include audio and video signal routing, data acquisition systems, and test equipment where low crosstalk (-90 dB at 100 kHz) and low charge injection (2 pC) preserve signal integrity.
Key ratings and what they mean for the BOM
The 3.5 kOhm on-resistance is relatively high compared to modern analog switches — expect a voltage drop of several millivolts at typical signal currents. This part suits high-impedance signal paths where the switch resistance does not load the source. The 1 µs turn-on and 500 ns turn-off times are adequate for audio switching and low-speed multiplexing but not for high-speed data or video line rates above a few megahertz. The 2 pC charge injection is low enough for sample-and-hold and DAC deglitching without external compensation. The -90 dB crosstalk at 100 kHz means adjacent channels stay isolated by better than 90 dB — important for precision multichannel measurements.
Temperature grade and deployment environment
Rated for the commercial temperature range of 0°C to 70°C, this part is intended for indoor, controlled-environment equipment such as benchtop instruments, audio gear, and office electronics. It is not specified for industrial or automotive environments where extended temperature or AEC-Q100 qualification is required. The 16-SOIC package (3.90 mm width) is a common footprint for analog switches and multiplexers, compatible with standard SOIC-16 land patterns.
Crosstalk and isolation performance
The -90 dB crosstalk at 100 kHz keeps adjacent channels isolated by better than 90 dB.