5 Ohm on-resistance and channel isolation for precision analog routing
The MAX4622ESE+T is a dual DPST (1:1 multiplexer/demultiplexer) analog switch from Analog Devices, built for routing precision analog signals without loading the source. Its 5 Ohm max on-resistance keeps voltage drop across the switch below 5 mV at 1 mA signal current — negligible in a 10-bit or 12-bit signal chain where the LSB is 2.4 mV on a 5 V reference. Channel-to-channel matching of 250 mOhm means the two switch paths track within 0.25 Ohm, important when the downstream differential amplifier expects equal series resistance in both legs. Crosstalk is specified at -60 dB at 1 MHz — this is the isolation between the two switch channels when one is active and the other is off. For a 10 kHz audio or instrumentation signal, the isolation is better than -80 dB (crosstalk improves at lower frequency), so a 5 Vpp signal on channel 1 leaks less than 500 µV into channel 2. The 34 pF off-capacitance on both source and drain pins contributes to this isolation; at 1 MHz the capacitive feedthrough is roughly -66 dB, consistent with the spec.
Wide supply range and charge injection trade-offs
Single-supply operation from 4.5 V to 36 V covers common rails: 5 V logic, 12 V industrial, 24 V fieldbus, and 36 V for legacy ±18 V analog designs. Dual-supply mode from ±4.5 V to ±18 V lets the switch handle bipolar signals up to ±15 V without clipping, which is the standard range for precision op-amp signal chains. The 500 pA max off-leakage at 25°C means the switch does not add measurable offset to a high-impedance sensor front-end — a 10 MOhm source sees 5 µV of additional offset from leakage. Charge injection is 480 pC — this is the charge dumped onto the signal line when the switch turns off. In a sample-and-hold or DAC deglitching circuit, 480 pC into a 10 nF hold capacitor creates a 48 mV glitch. For precision applications below 12 bits, an external hold capacitor above 100 nF or a post-switch buffer is needed to absorb the injected charge without disturbing the settled value. The 250 ns turn-on and 200 ns turn-off times set the maximum multiplexing rate at roughly 2 MHz for a 50% duty cycle, assuming the downstream amplifier settles within the on-time window.
Industrial temperature grade and package for surface-mount assembly
Tape & Reel packaging supports automated pick-and-place; the cut-tape option is available for prototype builds.