What this quad SPDT switch is for
The MAX4533CWP+T is a quad single-pole double-throw (SPDT) analog switch from Maxim Integrated, packing four independent 2:1 multiplexer/demultiplexer circuits into a 20-SOIC package. Each switch handles analog or digital signals with a maximum on-resistance of 175Ohm and channel-to-channel matching held to 1Ohm, so gain errors across channels stay tight. The 250ns turn-on and 150ns turn-off times make it fast enough for audio routing, test equipment signal chains, and data acquisition front-ends where you need to switch between two sources without loading the signal. Charge injection is a low 1.5pC, which matters when you are switching into a high-impedance node like a sample-and-hold or an ADC input — less glitch energy means fewer settling-time headaches.
Supply rails and where this part lives
This switch runs on either a single supply from 9V to 36V or dual supplies from ±4.5V to ±18V. That dual-supply range is the big deal here — it lets you switch bipolar signals without level-shifting or AC coupling. If your design already has ±15V rails for op-amps, this switch drops right onto them. The single-supply mode covers 12V and 24V industrial systems, but watch the signal swing: with a single 12V rail, the switch passes signals from ground up to about 11V, limited by the on-resistance curve. Off-leakage is rated at 20nA max, and channel capacitance is 5pF, so crosstalk stays at -66dB at 1MHz — clean enough for 16-bit audio paths and moderate-frequency analog multiplexing.
Temperature grade — indoor only
The MAX4533CWP+T is rated for the commercial temperature range of 0°C to 70°C.
Package and mounting for the bench
Surface-mount in a 20-SOIC wide-body package (0.295", 7.50mm width). The wide SOIC gives you more room between pins than the narrow version, which helps when you are hand-soldering a replacement on site with a fine-tip iron. No thermal pad, no exposed paddle — just a straightforward gull-wing package that aligns easily. The T suffix on the order code means it ships in Tape & Reel, but you can also get it as Cut Tape for small quantities. No lab, no bench, let us go — this is a part you can swap in the field with basic tools if you have a steady hand and good lighting.
Lifecycle and sourcing reality
That means you can qualify it into a new BOM without worrying about a last-time-buy window closing next quarter. No LTB math needed, no broker-scramble for obsolete stock.