SN74CBT3253DBR

具有 TTL 输入的 5V、4:1、2 通道模拟多路复用器

Undershoot Protection for Off-lsolation onA and B Ports Up To -2 V

Bidirectional Data Flow, With Near-ZeroPropagation Delay

Low ON-State Resistance (ron)Characteristics (ron = 3 2 Typical)

Low Input/Output Capacitance MinimizesLoading and Signal Distortion(Cio(OFF) = 5.5 pF Typical)

Data and Control inputs ProvideUndershoot Clamp Diodes

Low Power Consumption(lcc = 3 μA Max)

Vcc Operating Range From 4 V to 5.5 V

Data l/Os Support 0 to 5-V Signaling Levels(0.8-V,1.2-V,1.5-V, 1.8-V,2.5-V, 3.3-V, 5-V)Control inputs Can be Driven by TTL or5-V/3.3-V CMOS Outputs

off Supports Partial-Power-Down ModeOperation

Latch-Up Performance Exceeds 100 mA PerJESD 78, Class ll

ESD Performance Tested Per JESD 22-2000-V Human-Body Model(A114-B, Class ll)

1000-V Charged-Device Model (C101)

Supports l2C Bus Expansion

Supports Both Digital and AnalogApplications: USB Interface, Bus lsolation,Low-Distortion Signal Gating

description/ordering information

The SN74CBT3257C is a high-speed TTL-compatible FET multiplexer/demultiplexer with low ON-state resistance (ron), allowing for minimal propagation delay. Active Undershoot-Protection Circuitry on the A and B ports of the SN74CBT3257C provides protection for undershoot up to −2 V by sensing an undershoot event and ensuring that the switch remains in the proper OFF state.

The SN74CBT3257C is a 4-bit 1-of-2 multiplexer/demultiplexer with a single output-enable (OE select (S) input controls the data path of the multiplexer/demultiplexer. When OE ) input. The is low, the multiplexer/demultiplexer is enabled and the A port is connected to the B port, allowing bidirectional data flow between ports. When OE is high, the multiplexer/demultiplexer is disabled and a high-impedance state exists between the A and B ports.

This device is fully specified for partial-power-down applications using Ioff. The Ioff feature ensures that damaging current will not backflow through the device when it is powered down. The device has isolation during power off.

To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.