参数资料
型号: SN74LVC646ANSRE4
厂商: TEXAS INSTRUMENTS INC
元件分类: 总线收发器
英文描述: LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
封装: GREEN, PLASTIC, SOP-24
文件页数: 12/21页
文件大小: 472K
代理商: SN74LVC646ANSRE4
www.ti.com
DESCRIPTION/ORDERING INFORMATION (CONTINUED)
SN54LVC646A, SN74LVC646A
OCTAL BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCAS302J – JANUARY 1993 – REVISED AUGUST 2005
These devices consist of bus-transceiver circuits, D-type flip-flops, and control circuitry arranged for multiplexed
transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked
into the registers on the low-to-high transition of the appropriate clock (CLKAB or CLKBA) input. Figure 1
illustrates the four fundamental bus-management functions that are performed with the 'LVC646A devices.
Output-enable (OE) and direction-control (DIR) inputs control the transceiver functions. In the transceiver mode,
data present at the high-impedance port is stored in either register or in both.
The select-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. DIR
determines which bus receives data when OE is low. In the isolation mode (OE high), A data is stored in one
register and B data can be stored in the other register.
When an output function is disabled, the input function still is enabled and can be used to store and transmit
data. Only one of the two buses, A or B, can be driven at a time.
Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of these devices as translators
in a mixed 3.3-V/5-V system environment.
These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the
outputs, preventing damaging current backflow through the device when it is powered down.
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.
FUNCTION TABLE
INPUTS
DATA I/O
OPERATION OR
FUNCTION
OE
DIR
CLKAB
CLKBA
SAB
SBA
A1–A8
B1–B8
X
X
Input
Unspecified(1)
Store A, B unspecified(1)
X
X
Unspecified(1)
Input
Store B, A unspecified(1)
H
X
X
Input
Store and B data
H
X
H or L
X
Input disabled
Isolation, hold storage
L
X
L
Output
Input
Real-time B data to A bus
L
X
H or L
X
H
Output
Input
Stored B data to A bus
L
H
X
L
X
Input
Output
Real-time A data to B bus
L
H
H or L
X
H
X
Input
Output
Stored A data to B bus
(1)
The data-output functions can be enabled or disabled by various signals at OE and DIR. Data-input functions always are enabled; i.e.,
data at the bus terminals is stored on every low-to-high transition of the clock inputs.
2
相关PDF资料
PDF描述
SN74LVC646ADWRE4 LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
SN74LVC646APWTG4 LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
SN74LVC652ADWG4 LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
SN74LVC652ADW LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
SN74LVC652ANSRE4 LVC/LCX/Z SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24
相关代理商/技术参数
参数描述
SN74LVC646ANSRG4 功能描述:总线收发器 Octal Bus Transceivr And Register RoHS:否 制造商:Fairchild Semiconductor 逻辑类型:CMOS 逻辑系列:74VCX 每芯片的通道数量:16 输入电平:CMOS 输出电平:CMOS 输出类型:3-State 高电平输出电流:- 24 mA 低电平输出电流:24 mA 传播延迟时间:6.2 ns 电源电压-最大:2.7 V, 3.6 V 电源电压-最小:1.65 V, 2.3 V 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-48 封装:Reel
SN74LVC646APW 功能描述:总线收发器 Octal Bus Trncvr/Reg W/3-State Otpt RoHS:否 制造商:Fairchild Semiconductor 逻辑类型:CMOS 逻辑系列:74VCX 每芯片的通道数量:16 输入电平:CMOS 输出电平:CMOS 输出类型:3-State 高电平输出电流:- 24 mA 低电平输出电流:24 mA 传播延迟时间:6.2 ns 电源电压-最大:2.7 V, 3.6 V 电源电压-最小:1.65 V, 2.3 V 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-48 封装:Reel
SN74LVC646APWE4 功能描述:总线收发器 Octal Bus Trncvr/Reg W/3-State Otpt RoHS:否 制造商:Fairchild Semiconductor 逻辑类型:CMOS 逻辑系列:74VCX 每芯片的通道数量:16 输入电平:CMOS 输出电平:CMOS 输出类型:3-State 高电平输出电流:- 24 mA 低电平输出电流:24 mA 传播延迟时间:6.2 ns 电源电压-最大:2.7 V, 3.6 V 电源电压-最小:1.65 V, 2.3 V 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-48 封装:Reel
SN74LVC646APWG4 功能描述:总线收发器 Octal Bus Transceivr And Register RoHS:否 制造商:Fairchild Semiconductor 逻辑类型:CMOS 逻辑系列:74VCX 每芯片的通道数量:16 输入电平:CMOS 输出电平:CMOS 输出类型:3-State 高电平输出电流:- 24 mA 低电平输出电流:24 mA 传播延迟时间:6.2 ns 电源电压-最大:2.7 V, 3.6 V 电源电压-最小:1.65 V, 2.3 V 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-48 封装:Reel
SN74LVC646APWR 功能描述:总线收发器 Tri-St. Octal Bus RoHS:否 制造商:Fairchild Semiconductor 逻辑类型:CMOS 逻辑系列:74VCX 每芯片的通道数量:16 输入电平:CMOS 输出电平:CMOS 输出类型:3-State 高电平输出电流:- 24 mA 低电平输出电流:24 mA 传播延迟时间:6.2 ns 电源电压-最大:2.7 V, 3.6 V 电源电压-最小:1.65 V, 2.3 V 最大工作温度:+ 85 C 封装 / 箱体:TSSOP-48 封装:Reel