Overview
The SN74CB3Q3251RGYR, produced by Texas Instruments, is a 1-of-8 FET multiplexer/demultiplexer designed for high-bandwidth applications. This device operates as a 2.5-V/3.3-V low-voltage bus switch, making it ideal for broadband communications, networking, and data-intensive computing systems. It features a single output-enable (OE) input and select inputs (S0, S1, S2) that control the data path, allowing bidirectional data flow between ports when enabled.
The SN74CB3Q3251 utilizes a charge pump to elevate the gate voltage of the pass transistor, resulting in low and flat ON-state resistance. This design minimizes propagation delay and supports rail-to-rail switching on the data input/output (I/O) ports. The device also includes low data I/O capacitance to reduce capacitive loading and signal distortion.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage Range (VCC) | 2.3 | 3.6 | V | |
| Control Input Voltage Range (VIN) | –0.5 | 7 | V | |
| Switch I/O Voltage Range (VI/O) | –0.5 | 7 | V | |
| Operating Free-Air Temperature (TA) | –40 | 85 | °C | |
| High-Level Control Input Voltage (VIH) | 2 | 5.5 | V | |
| Low-Level Control Input Voltage (VIL) | 0 | 0.8 | V | |
| ON-State Switch Current (II/O) | ±64 | mA | ||
| Input/Output Capacitance (Cio(OFF)) | 3.5 | 4.5 | pF | |
| Propagation Delay (tpd) | ns | |||
| Switching Frequency (fOE or fS) | 20 | MHz |
Key Features
- High-bandwidth data path (up to 500 MHz)
- Low power consumption (ICC = 1 mA Typ)
- Low and flat ON-state resistance (ron = 4 Ω Typ)
- Rail-to-rail switching on data I/O ports
- 5-V tolerant I/Os with device powered up or powered down
- Data I/Os support 0- to 5-V signaling levels
- Control inputs can be driven by TTL or 5-V/3.3-V CMOS outputs
- Bidirectional data flow with near-zero propagation delay
- Low input/output capacitance minimizes loading and signal distortion
- Supports partial-power-down mode operation
- ESD performance tested per JESD 22 (2000-V Human-Body Model, 1000-V Charged-Device Model)
Applications
- PCI interface
- Differential signal interface
- Memory interleaving
- Bus isolation
- Low-distortion signal gating
- Broadband communications
- Networking
- Data-intensive computing systems
Q & A
- What is the primary function of the SN74CB3Q3251?
The SN74CB3Q3251 is a 1-of-8 FET multiplexer/demultiplexer designed for high-bandwidth applications.
- What is the operating voltage range of the SN74CB3Q3251?
The device operates within a supply voltage range of 2.3 V to 3.6 V.
- What are the key features of the SN74CB3Q3251?
Key features include high-bandwidth data path, low power consumption, low and flat ON-state resistance, and rail-to-rail switching on data I/O ports.
- How does the SN74CB3Q3251 handle ESD protection?
The device has ESD performance tested per JESD 22, including 2000-V Human-Body Model and 1000-V Charged-Device Model.
- What are the typical applications of the SN74CB3Q3251?
Typical applications include PCI interface, differential signal interface, memory interleaving, bus isolation, and low-distortion signal gating.
- How does the SN74CB3Q3251 support partial-power-down mode?
The device supports partial-power-down mode operation using Ioff circuitry, which prevents damaging current backflow when the device is powered down.
- What is the maximum switching frequency of the SN74CB3Q3251?
The maximum switching frequency is 20 MHz for both OE and S inputs.
- What is the typical ON-state resistance of the SN74CB3Q3251?
The typical ON-state resistance (ron) is 4 Ω.
- How does the SN74CB3Q3251 minimize signal distortion?
The device minimizes signal distortion through low input/output capacitance.
- What are the package options available for the SN74CB3Q3251?
Package options include SSOP (DBQ), TVSOP (DGV), TSSOP (PW), and QFN (RGY).
- What is the operating temperature range of the SN74CB3Q3251?
The operating free-air temperature range is from –40°C to 85°C.
