What the DG445DY+ is and where it fits
The Maxim Integrated DG445DY+ is a quad SPST-NO analog switch in a 16-SOIC surface-mount package. Each of the four independent switches is normally open, controlled by a single logic input. The part is built for routing analog or digital signals up to the supply rails, with a single-supply range of 10V to 30V or a dual-supply range of ±4.5V to ±20V. Typical applications include audio signal routing, data acquisition systems, test equipment, and industrial analog multiplexing where low charge injection (5pC) and channel-to-channel matching (4 ohm max) matter for signal fidelity.
Key ratings and what they mean for the BOM
The 85 ohm max on-resistance is the series resistance each switch adds to the signal path. For a precision analog front-end, that resistance and its matching (4 ohm max between channels) will affect gain accuracy and offset — plan to calibrate or buffer if the load impedance is below 10 kohm. Switching times of 250ns on and 170ns off set the throughput limit for multiplexed signals. At 1 MHz the crosstalk sits at -100 dB, which is a strong isolation figure — adjacent channels won't bleed into each other in audio or low-frequency precision applications. The charge injection of 5 pC means a small glitch couples onto the signal when the switch opens or closes; acceptable for most line-level audio but worth noting for sample-and-hold or high-impedance nodes. Operating temperature from -40°C to 85°C covers industrial enclosures, outdoor telecom cabinets, and factory-floor control panels. The 16-SOIC package is a standard footprint for mixed-signal boards; verify clearance for the 3.90 mm body width if retrofitting a legacy layout.
Lifecycle and sourcing reality
The DG445DY+ carries an active product status and is ROHS3 compliant.