Quad SPST switch with 85 Ohm Ron and -100 dB crosstalk
The DG442CY+ is a quad single-pole single-throw (SPST) normally-open analog switch from Analog Devices, packaged in a 16-SOIC. Each of the four independent switches connects a signal path with a maximum on-resistance of 85 Ohm, making it suitable for routing audio, low-frequency analog, or digital signals in precision instrumentation and data-acquisition front-ends.
Switching speed and signal isolation for multiplexed paths
Maximum turn-on time is 250 ns and turn-off is 170 ns, which sets the channel-switching rate for a multiplexed ADC input or sample-and-hold front-end — at 250 ns the switch can cycle through four channels in about 1 µs, staying ahead of a 1 MSPS converter's acquisition window. Crosstalk between channels is -100 dB at 1 MHz, meaning a full-swing signal on one channel couples less than 10 µV into an adjacent off channel at that frequency — relevant for precision multiplexers where channel bleed would corrupt the measurement. Charge injection is 5 pC typical, which translates to a voltage glitch of roughly 1.25 mV when switching into a 4 pF load capacitance — low enough for 12-bit systems but worth budgeting in 16-bit or higher-resolution paths.
Supply rails, leakage, and channel matching for BOM fit
Maximum off-state leakage is 500 pA at 25 °C, and channel capacitance is 4 pF for both source and drain — together they keep the off-channel loading below 0.5 pF equivalent at low frequencies, preserving the signal integrity of the active path. Channel-to-channel on-resistance matching is 4 Ohm maximum, so the insertion loss across all four paths stays within 5 % of each other — useful when the switch is part of a gain-setting network or a programmable attenuator where path-to-path consistency matters more than the absolute Ron value.