SN74CB3T3245

Features:

` VCC Operating Range From 2.3 V to 3.6 V
` Standard '245-Type Pinout ` 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) ` Output Voltage Translation Tracks V_CC
` Control Inputs Can Be Driven by TTL or ` Supports Mixed-Mode Signal Operation on All 5-V/3.3-V CMOS Outputs Data I/O Ports
` Ioff Supports Partial-Power-Down Mode 5-V Input Down to 3.3-V Output Level Shift Operation With 3.3-V V<sub>CC</sub>
` Latch-Up Performance Exceeds 250 mA 5-V/3.3-V Input Down to 2.5-V Output Level Per JESD 17 Shift With 2.5-V V_CC
` ESD Performance Tested Per JESD 22 ` 5-V-Tolerant I/Os With Device Powered Up or Powered Down 2000-V Human-Body Model (A114-B, Class II) ` Bidirectional Data Flow With Near-Zero Propagation Delay 1000-V Charged-Device Model (C101)
` Low ON-State Resistance (r_on) Characteristics ` Supports Digital Applications: Level (r<sub>on</sub> = 5 W Typ) Translation, PCI Interface, USB Interface, Memory Interleaving, Bus Isolation ` Low Input/Output Capacitance Minimizes Loading (C_io(OFF) = 5 pF Typ) ` Ideal for Low-Power Portable Equipment
` Data and Control Inputs Provide Undershoot Clamp Diodes
` Low Power Consumption (I_CC = 40 mA Max)

Pinout




Specifications

			MIN	MAX	UNIT
VCC	Supply voltage range		0.5	7	V
VIN	Control input voltage range(2) (3)		0.5	7	V
VI/O	Switch I/O voltage range(2) (3) (4)		0.5	7	V
IIK	Control input clamp current	VIN < 0		50	mA
II/OK	I/O port clamp current	VI/O < 0		50	mA
IIO	ON-state switch current(5)			±128	mA
	Continuous current through VCC or GND			±100	mA
qJA	Package thermal impedance(6)	DBQ package		68	°C/W
		DGV package		92
		DW package		58
		PW package		83
Tstg	Storage temperature range		65	150	°C

Description

   The SN74CB3T3245 is a high-speed TTL-compatible FET bus switch with low ON-state resistance (r_on), allowing for minimal propagation delay. The device fully supports mixed-mode signal operation on all data I/O ports by providing voltage translation that tracks V_CC. The SN74CB3T3245 supports systems using 5-V TTL, 3.3-V LVTTL, and 2.5-V CMOS switching standards, as well as user-defined switching levels (see Figure 1).

   The SN74CB3T3245 is an 8-bit bus switch with a single ouput-enable (OE) input and a standard '245 pinout. When OE is low, the 8-bit 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 8-bit bus switch is OFF, and a high-impedance state exists between the A and B ports.

   This SN74CB3T3245 device is fully specified for partial-power-down applications using I_off. 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 SN74CB3T3245 high-impedance state during power up or power down, OE should be tied to V_CC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.