SN74LVTH182512 - 具有 18 位通用总线收发器的 3.3V ABT 扫描测试设备

SN74LVTH182512是TI德州仪器公司的一款边界扫描(JTAG)逻辑产品，SN74LVTH182512是具有 18 位通用总线收发器的 3.3V ABT 扫描测试设备，本站介绍了SN74LVTH182512的封装应用图解、特点和优点、功能等，并给出了与SN74LVTH182512相关的TI元器件型号供参考。

SN74LVTH182512 - 具有 18 位通用总线收发器的 3.3V ABT 扫描测试设备 - 边界扫描(JTAG)逻辑 - 特殊逻辑 - 德州仪器

产品描述

The 'LVTH18512 and 'LVTH182512 scan test devices with 18-bit universal bus transceivers are members of the Texas Instruments SCOPETM testability integrated-circuit family. This family of devices supports IEEE Std 1149.1-1990 boundary scan to facilitate testing of complex circuit-board assemblies. Scan access to the test circuitry is accomplished via the 4-wire test access port (TAP) interface.

Additionally, these devices are designed specifically for low-voltage (3.3-V) VCC operation, but with the capability to provide a TTL interface to a 5-V system environment.

In the normal mode, these devices are 18-bit universal bus transceivers that combine D-type latches and D-type flip-flops to allow data flow in transparent, latched, or clocked modes. They can be used either as two 9-bit transceivers or one 18-bit transceiver. The test circuitry can be activated by the TAP to take snapshot samples of the data appearing at the device pins or to perform a self test on the boundary-test cells. Activating the TAP in the normal mode does not affect the functional operation of the SCOPETM universal bus transceivers.

Data flow in each direction is controlled by output-enable (OEAB\ and OEBA\), latch-enable (LEAB and LEBA), and clock (CLKAB and CLKBA) inputs. For A-to-B data flow, the devices operate in the transparent mode when LEAB is high. When LEAB is low, the A data is latched while CLKAB is held at a static low or high logic level. Otherwise, if LEAB is low, A data is stored on a low-to-high transition of CLKAB. When OEAB\ is low, the B outputs are active. When OEAB\ is high, the B outputs are in the high-impedance state. B-to-A data flow is similar to A-to-B data flow but uses the OEBA\, LEBA, and CLKBA inputs.

In the test mode, the normal operation of the SCOPETM universal bus transceivers is inhibited, and the test circuitry is enabled to observe and control the I/O boundary of the device. When enabled, the test circuitry performs boundary-scan test operations according to the protocol described in IEEE Std 1149.1-1990.

Four dedicated test pins are used to observe and control the operation of the test circuitry: test data input (TDI), test data output (TDO), test mode select (TMS), and test clock (TCK). Additionally, the test circuitry performs other testing functions such as parallel-signature analysis (PSA) on data inputs and pseudo-random pattern generation (PRPG) from data outputs. All testing and scan operations are synchronized to the TAP interface.

Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level.

The B-port outputs of 'LVTH182512, which are designed to source or sink up to 12 mA, include equivalent 25- series resistors to reduce overshoot and undershoot.

The SN54LVTH18512 and SN54LVTH182512 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74LVTH18512 and SN74LVTH182512 are characterized for operation from -40°C to 85°C.

产品特性

Members of the Texas Instruments SCOPETM Family of Testability Products
Members of the Texas Instruments WidebusTM Family
State-of-the-Art 3.3-V ABT Design Supports Mixed-Mode Signal Operation (5-V Input and Output Voltages With 3.3-V VCC)
Support Unregulated Battery Operation Down to 2.7 V
UBTTM (Universal Bus Transceiver) Combines D-Type Latches and D-Type Flip-Flops for Operation in Transparent, Latched, or Clocked Mode
Bus Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors
B-Port Outputs of 'LVTH182512 Devices Have Equivalent 25- Series Resistors, So No External Resistors Are Required
Compatible With the IEEE Std 1149.1-1990 (JTAG) Test Access Port and Boundary-Scan Architecture
SCOPETM Instruction Set
- IEEE Std 1149.1-1990 Required Instructions and Optional CLAMP and HIGHZ
- Parallel-Signature Analysis at Inputs
- Pseudo-Random Pattern Generation From Outputs
- Sample Inputs/Toggle Outputs
- Binary Count From Outputs
- Device Identification
- Even-Parity Opcodes
Package Options Include 64-Pin Plastic Thin Shrink Small Outline (DGG) and 64-Pin Ceramic Dual Flat (HKC) Packages Using 0.5-mm Center-to-Center Spacings

SCOPE, Widebus, and UBT are trademarks of Texas Instruments Incorporated.

下面可能是您感兴趣的TI德州仪器公司边界扫描(JTAG)逻辑元器件

TI公司产品现货专家，订购TI公司产品不限最低起订量，TI芯片大陆现货即时发货，香港库存3-5天发货，海外库存7-10天发货

寻找全球TI代理商现货货源 - TI公司（德州仪器）电子元件在线订购