The SN3257-Q1 is an
automotive grade complementary metal-oxide semiconductor (CMOS) switch that supports
high speed signals with low propagation delay. The SN3257-Q1 offers a
2:1 (SPDT) switch configuration with 4-channels making it ideal for multi-lane
protocols such as SPI and I2S. The device supports bidirectional analog and digital
signals on the source (SxA, SxB) and drain (Dx) pins and can pass signals above
supply up to VDD x 2, with a maximum input and output voltage of 5.5
V.The SN3257-Q1 has an
active low EN pin that is used to enable and disable all
channels simultaneously. When the EN pin is LOW, one of the two
switch paths is selected based on the state of SEL pin.Powered-off protection up to 3.6 V on
the signal path of the SN3257-Q1 provides isolation when the supply
voltage is removed (VDD = 0 V). Without this protection feature, switches
can back-power the supply rail through an internal ESD diode and cause potential
damage to the system.Fail-safe logic circuitry allows
voltages on the logic control pins to be applied before the supply pin, protecting
the device from potential damage. Both logic control inputs have 1.8 V logic
compatible thresholds, ensuring both TTL and CMOS logic compatibility. Integrated
pull down resistor on the logic pins removes external components to reduce system
size and cost.
