TI SN74CB3Q3257DBQR

The SN74CB3Q3257 is a high-bandwidth FET bus switch utilizing a charge pump to elevate the gate voltage of the pass transistor, providing a low and flat ON-state resistance (rₒₙ). The low and flat ON-state resistance allows for minimal propagation delay and supports rail-to-rail switching on the data input/output (I/O) ports. The device also features low data I/O capacitance to minimize capacitive loading and signal distortion on the data bus. Specifically designed to support high-bandwidth applications, the SN74CB3Q3257 provides an optimized interface solution ideally suited for broadband communications, networking, and data-intensive computing systems. The SN74CB3Q3257 is a 4-bit 1-of-2 high-speed FET multiplexer/demultiplexer with a single output-enable (OE̅) input. The select (S) input controls the data path of the multiplexer/demultiplexer. When OE̅ 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 Iₒₕ. The Iₒff circuitry prevents damaging current 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, OE̅ 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.

• High-Bandwidth Data Path (up to 500 MHz)
• 5-V Tolerant I/Os With Device Powered Up or Powered Down
• Low and Flat ON-State Resistance (rₒₙ) Characteristics Over Operating Range (rₒₙ = 4 Ω Typ)
• Rail-to-Rail Switching on Data I/O Ports
• -d- to 5-V Switching With 3.3-V VCC
• -d- to 3.3-V Switching With 3.5 V VCC
• Bidirectional Data Flow With Near-Zero Propagation Delay
• Low Input/Output Capacitance Minimizes Loading and Signal Distortion (Cᵢₒ₍ₒₚₚ₎ = 3.5 pF Typ)
• Fast Switching Frequency (fₒₑ = 20 MHz Max)
• Data and Control Inputs Provide Undershoot Clamp Diodes
• Low Power Consumption (Icc = 0.7 mA Typ)
• VCC Operating Range From 2.3 V to 3.6 V
• Data I/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 or 5-V/3.3-V CMOS Outputs
• Iₒff Supports Partial-Power-Down Mode Operation
• Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
• ESD Performance Tested Per JESD 22
  • 2000-V Human-Body Model (A114-B, Class II)
  • 1000-V Charged-Device Model (C101)
• Supports Both Digital and Analog Applications: USB Interface, Differential Signal Interface, Bus Isolation, Low-Distortion Signal Gating

• broadband communications
• networking
• data-intensive computing systems