Quad SPDT analog switch with tight channel matching
The MAX333ACAP+T from Analog Devices is a quad single-pole double-throw (SPDT) analog switch — four independent 2:1 multiplexer/demultiplexer circuits in one 20-SSOP package. Each switch handles signals up to the supply rails with a maximum on-resistance of 45 ohms and channel-to-channel matching held to 2 ohms, which keeps gain errors consistent across all four paths. Switching is fast: 175 ns turn-on, 145 ns turn-off, so it works in sample-and-hold front ends or audio routing where timing matters. The wide supply range — single 10 V to 30 V, or dual ±4.5 V to ±20 V — means it can pass bipolar signals directly without external level translation. Charge injection is a low 2 pC, reducing glitch energy into sensitive loads. Crosstalk between channels is -78 dB at 1 MHz, clean enough for multiplexing low-level analog signals in instrumentation or data acquisition.
Supply flexibility and signal handling
This part runs on either a single positive rail (10 V to 30 V) or dual supplies (±4.5 V to ±20 V). With dual supplies, it can switch bipolar analog signals — audio, sensor outputs, or ±10 V industrial control voltages — without adding a DC bias network. The 45 ohm on-resistance is flat enough (2 ohm max channel matching) that it won't introduce significant attenuation or distortion in most signal chains. Off-leakage is just 250 pA max, and channel capacitance is 5 pF, so it loads the source minimally at high frequencies.
Package and rework
The 20-SSOP package (0.209 inch body width, 5.30 mm) has visible gull-wing leads. It reflows with standard solder profiles and can be hand-soldered or hot-air reworked.
Lifecycle and compliance
The MAX333ACAP+T is listed as Active with ROHS3 compliance. There is no end-of-life notice or last-time-buy window. It is suitable for both new designs and ongoing production replenishment through independent distribution.