An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
SN74CB3Q3257
SCDS135D – SEPTEMBER 2003 – REVISED JULY 2018
SN74CB3Q3257 4-Bit 1-of-2 FET Multiplexer/Demultiplexer
2.5-V/3.3-V Low-Voltage High-Bandwidth Bus Switch
1
(1) For additional information regarding the performance
characteristics of the CB3Q family, refer to the TI application
report, ,CBT-C, CB3T, and CB3Q Signal-Switch Families
SCDA008.
1 Features
1
• 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 Typical)Ω
• Rail-to-Rail Switching on Data I/O Ports
– 0- to 5-V Switching With 3.3-V VCC
– 0- to 3.3-V Switching With 2.5-V VCC
• Bidirectional Data Flow With Near-Zero
Propagation Delay
• Low Input and Output Capacitance Minimizes
Loading and Signal Distortion
(Cio(OFF) = 3.5 pF Typical)
• Fast Switching Frequency (f OE = 20 MHz
Maximum)
• Data and Control Inputs Provide Undershoot
Clamp Diodes
• Low Power Consumption
(ICC = 0.7 mA Typical)
• 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
• Io 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, Dierential Signal Interface,
Bus Isolation, Low-Distortion Signal Gating (1)
2 Applications
• IP Phones: Wired and Wireless
• Optical Modules
• Optical Networking: Video Over Fiber and EPON
• Private Branch Exchange (PBX)
• WiMAX and Wireless Infrastructure Equipment
3 Description
The SN74CB3Q3257 device is a high-bandwidth FET
bus switch utilizing a charge pump to elevate the gate
voltage of the pass transistor, providing a low and at
ON-state resistance (ron).
Device Information(1)
PART NUMBER PACKAGE BODY SIZE (NOM)
SN74CB3Q3257DGV TVSOP (16) 3.60 mm × 4.40 mm
SN74CB3Q3257DBQ SSOP (16) 4.90 mm × 3.90 mm
SN74CB3Q3257PW TSSOP (16) 5.00 mm × 4.40 mm
SN74CB3Q3257RGY VQFN (16) 4.00 mm × 3.50 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Logic Diagram (Positive Logic)
