SN74CB3Q3245 8 BIT FET BUS SWITCH 2.5 V/3.3 V LOW VOLTAGE HIGH BANDWIDTH BUS SWITCH
SCDS124B − JULY 2003 − REVISED NOVEMBER 2003
D High-Bandwidth Data Path D D D D D D D
(Up to 500 MHz†) Equivalent to IDTQS3VH384 Device 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 Typical) 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/Output Capacitance Minimizes Loading and Signal Distortion (Cio(OFF) = 3.5 pF Typical) Fast Switching Frequency (fOE = 20 MHz Max)
D Data and Control Inputs Provide D D D D D D D
Undershoot Clamp Diodes Low Power Consumption (ICC = 1 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 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: PCI Interface, Differential Signal Interface, Memory Interleaving, Bus Isolation, Low-Distortion Signal Gating
RGY PACKAGE (TOP VIEW)
† 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, literature number SCDA008. DBQ, DGV, OR PW PACKAGE (TOP VIEW)
D
NC A1 A2 A3 A4 A5 A6 A7 A8 GND
1 2 3 4 5 6 7 8 9 10
20 19 18 17 16 15 14 13 12 11
VCC OE B1 B2 B3 B4 B5 B6 B7 B8
1
20 19 OE 18 B1 17 B2 16 B3 15 B4 14 B5 13 B6 12 B7
A1 A2 A3 A4 A5 A6 A7 A8
2 3 4 5 6 7 8 9 10 11
NC − No internal connection
NC − No internal connection
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Copyright 2003, Texas Instruments Incorporated
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GND
B8
VCC
NC
1
SCDS124B − JULY 2003 − REVISED NOVEMBER 2003
SN74CB3Q3245 8 BIT FET BUS SWITCH 2.5 V/3.3 V LOW VOLTAGE HIGH BANDWIDTH BUS SWITCH
description/ordering information
The SN74CB3Q3245 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 SN74CB3Q3245 provides an optimized interface solution ideally suited for broadband communications, networking, and data-intensive computing systems. The SN74CB3Q3245 is organized as an 8-bit bus switch with a single output-enable (OE) input. When OE is low, the bus switch is ON and the A port is connected to the B port, allowing bidirectional data flow between ports. When OE is high, the bus switch is OFF 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 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, 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. ORDERING INFORMATION
TA QFN − RGY SSOP (QSOP) − DBQ −40°C to 85°C TSSOP − PW TVSOP − DGV PACKAGE† Tape and reel Tape and reel Tube Tape and reel Tape and reel ORDERABLE PART NUMBER SN74CB3Q3245RGYR SN74CB3Q3245DBQR SN74CB3Q3245PW SN74CB3Q3245PWR SN74CB3Q3245DGVR BU245 BU245 TOP-SIDE MARKING BU245 CB3Q3245
VFBGA − GQN Tape and reel SN74CB3Q3245GQNR BU245 † Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at www.ti.com/sc/package. GQN PACKAGE (TOP VIEW) 1 A B C D E 2 3 4 A B C D E
terminal assignments
1 A1 A3 A5 A7 GND 2 NC B2 A4 B6 A8 3 VCC A2 B4 A6 B8 4 OE B1 B3 B5 B7
NC − No internal connection
FUNCTION TABLE INPUT OE L H INPUT/OUTPUT A B Z FUNCTION A port = B port Disconnect
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POST OFFICE BOX 655303
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SN74CB3Q3245 8 BIT FET BUS SWITCH 2.5 V/3.3 V LOW VOLTAGE HIGH BANDWIDTH BUS SWITCH
SCDS124B − JULY 2003 − REVISED NOVEMBER 2003
logic diagram (positive logic)
2 A1 SW 18 B1
9 A8 SW
11 B8
19 OE
Pin numbers shown are for the DBQ, DGV, PW, and RGY packages.
simplified schematic, each FET switch (SW)
A VCC B
Charge Pump
EN† † EN is the internal enable signal applied to the switch.
POST OFFICE BOX 655303
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SCDS124B − JULY 2003 − REVISED NOVEMBER 2003
SN74CB3Q3245 8 BIT FET BUS SWITCH 2.5 V/3.3 V LOW VOLTAGE HIGH BANDWIDTH BUS SWITCH
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 4.6 V Control input voltage range, VIN (see Notes 1 and 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V Switch I/O voltage range, VI/O (see Notes 1, 2, and 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V Control input clamp current, IIK (VIN < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −50 mA I/O port clamp current, II/OK (VI/O < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −50 mA ON-state switch current, II/O (see Note 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±64 mA Continuous current through VCC or GND terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±100 mA Package thermal impedance, θJA (see Note 5): DBQ package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68°C/W (see Note 5): DGV package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92°C/W (see Note 5): GQN package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78°C/W (see Note 5): PW package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83°C/W (see Note 6): RGY package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37°C/W Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. All voltages are with respect to ground unless otherwise specified. 2. The input and output voltage ratings may be exceeded if the input and output clamp-current ratings are observed. 3. VI and VO are used to denote specific conditions for VI/O. 4. II and IO are used to denote specific conditions for II/O. 5. The package thermal impedance is calculated in accordance with JESD 51-7. 6. The package thermal impedance is calculated in accordance with JESD 51-5.
recommended operating conditions (see Note 7)
MIN VCC VIH VIL VI/O TA Supply voltage High-level control input voltage Low-level control input voltage Data input/output voltage Operating free-air temperature VCC = 2.3 V to 2.7 V VCC = 2.7 V to 3.6 V VCC = 2.3 V to 2.7 V VCC = 2.7 V to 3.6 V 2.3 1.7 2 0 0 0 −40 MAX 3.6 5.5 5.5 0.7 0.8 5.5 85 V V °C V UNIT V
NOTE 7: All unused control inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74CB3Q3245 8 BIT FET BUS SWITCH 2.5 V/3.3 V LOW VOLTAGE HIGH BANDWIDTH BUS SWITCH
SCDS124B − JULY 2003 − REVISED NOVEMBER 2003
electrical characteristics over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER VIK IIN IOZ‡ Ioff ICC ∆ICC§ ICCD¶ Cin Control inputs Per control input Control inputs Control inputs VCC = 3.6 V, VCC = 3.6 V, VCC = 3.6 V, VCC = 0, VCC = 3.6 V, TEST CONDITIONS II = −18 mA VIN = 0 to 5.5 V VO = 0 to 5.5 V, VI = 0, VO = 0 to 5.5 V, II/O = 0, Switch ON or OFF, Switch OFF, VIN = VCC or GND VI = 0 VIN = VCC or GND Other inputs at VCC or GND 0.30 2.5 3.5 9 4 4.5 4 4 1 MIN TYP† MAX −1.8 ±1 ±1 1 2 30 0.35 3.5 5 11 8 9 6 8 Ω UNIT V µA µA µA mA µA mA/ MHz pF pF pF
VCC = 3.6 V, One input at 3 V, VCC = 3.6 V, A and B ports open, Control input switching at 50% duty cycle VCC = 3.3 V, VCC = 3.3 V, VCC = 3.3 V, VCC = 2.3 V, TYP at VCC = 2.5 V VCC = 3 V
Cio(OFF) Cio(ON)
VIN = 5.5 V, 3.3 V, or 0 Switch OFF, VI/O = 5.5 V, 3.3 V, or 0 VIN = VCC or GND, Switch ON, VIN = VCC or GND, VI = 0, VI = 1.7 V, VI = 0, VI = 2.4 V, VI/O = 5.5 V, 3.3 V, or 0 IO = 30 mA IO = −15 mA IO = 30 mA I
