The TL2218-285 is a current-mode 9-channel monolithic terminator specially designed for single-ended small-computer-systems-interface (SCSI) bus termination. A user-controlled disable function is provided to reduce standby power. No impedance-matching resistors or other external components are required for its operation as a complete terminator.

The device operates over a wide termination-voltage (V_term^[dagger]) range of 3.5 V to 5.5 V, offering an extra 0.5 V of operating range when compared to the minimum termination voltage of 4 V required by other integrated active terminators. The TL2218-285 functions as a current-sourcing terminator and supplies a constant output current of 23 mA into each asserted line. When a line is deasserted, the device senses the rising voltage level and begins to function as a voltage source, supplying a fixed output voltage of 2.85 V. The TL2218-285 features compatibility with active negation drivers and has a typical sink current capability of 20 mA.

The TL2218-285 is able to ensure that maximum current is applied at the first high-level step. This performance means that the device should provide a first high-level step exceeding 2 V even at a 10-MHz rate. Therefore, noise margins are improved considerably above those provided by resistive terminators.

A key difference between the TL2218-285 current-mode terminator and a Boulay terminator is that the TL2218-285 does not incorporate a low dropout regulator to set the output voltage to 2.85 V. In contrast with the Boulay termination concept, the accuracy of the 2.85 V is not critical with the current-mode method used in the TL2218-285 because this voltage does not determine the driver current. Therefore, the primary device specifications are not the same as with a voltage regulator but are more concerned with output current.

The DISABLE\ terminal is TTL compatible and must be taken low to shut down the outputs. The device is normally active, even when DISABLE\ is left floating. In the disable mode, only the device startup circuits remain active, thereby reducing the supply current to just 500 uA. Output capacitance in the shutdown mode is typically 6 pF.

The TL2218-285 has on-board thermal regulation and current limiting, thus eliminating the need for external protection circuitry. A thermal regulation circuit that is designed to provide current limiting, rather than an actual thermal shutdown, is included in the individual channels of the TL2218-285. When a system fault occurs that leads to excessive power dissipation by the terminator, the thermal regulation circuit causes a reduction in the asserted-line output current sufficient to maintain operation. This feature allows the bus to remain active during a fault condition, which permits data transfer immediately upon removal of the fault. A terminator with thermal shutdown does not allow for data transfer until sufficient cooling has occurred. Another advantage offered by the TL2218-285 is a design that does not require costly laser trimming in the manufacturing process.

The TL2218-285 is characterized for operation over the virtual junction temperature range of 0°C to 125°C.

• Operating temperature range (C)
• 0 to 125

TL2218-285的完整型号有：TL2218-285PW、TL2218-285PWR，以下是这些产品的关键参数及官网采购报价：

TL2218-285PW，工作温度：0 to 125，封装：TSSOP (PW)-20，包装数量MPQ：70个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网TL2218-285PW的批量USD价格：2.063（1000+）

TL2218-285PWR，工作温度：0 to 125，封装：TSSOP (PW)-20，包装数量MPQ：2000个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAU，TI官网TL2218-285PWR的批量USD价格：1.779（1000+）

PSPICE-FOR-TI — 适用于 TI 设计和模拟工具的 PSpice

PSpice for TI 可提供帮助评估模拟电路功能的设计和仿真环境。此功能齐全的设计和仿真套件使用 Cadence 的模拟分析引擎。PSpice for TI 可免费使用，包括业内超大的模型库之一，涵盖我们的模拟和电源产品系列以及精选的模拟行为模型。

借助?PSpice for TI 的设计和仿真环境及其内置的模型库，您可对复杂的混合信号设计进行仿真。创建完整的终端设备设计和原型解决方案，然后再进行布局和制造，可缩短产品上市时间并降低开发成本。

在?PSpice for TI 设计和仿真工具中，您可以搜索 TI (...)

TINA-TI — 基于 SPICE 的模拟仿真程序

TINA-TI 提供了 SPICE 所有的传统直流、瞬态和频域分析以及更多。TINA 具有广泛的后处理功能，允许您按照希望的方式设置结果的格式。虚拟仪器允许您选择输入波形、探针电路节点电压和波形。TINA 的原理图捕获非常直观 - 真正的“快速入门”。

TINA-TI 安装需要大约 500MB。直接安装，如果想卸载也很容易。我们相信您肯定会爱不释手。

TINA 是德州仪器 (TI) 专有的 DesignSoft 产品。该免费版本具有完整的功能，但不支持完整版 TINA 所提供的某些其他功能。

如需获取可用 TINA-TI 模型的完整列表，请参阅：SpiceRack - 完整列表

需要 HSpice (...)