SP485REP-L - 1/10 Unit Load RS-485 Transceiver | Exar
料号： SP485REP-L ✓ 量产中SP485REP-L 概述
An RS-485 transceiver is an interface IC that combines a differential line driver and differential receiver, allowing equipment to communicate reliably over noisy, long cable runs. The half-duplex arrangement means the driver and receiver share the same differential pair, with direction controlled by the design. As a universal bus transceiver, the SP485REP-L belongs to the interface IC hierarchy: bus transceiver, line transceiver, physical-layer interface, and communication semiconductor.
The principal feature is its 1/10 unit-load receiver input. A lower unit load reduces the loading placed on a shared bus, while the specified typical input resistance of 150 kOhm helps preserve driver signal integrity. The result is support for more than 400 transceivers on a single transmission line. Half-duplex operation also reduces wiring complexity by sharing one bus pair rather than requiring separate transmit and receive pairs.
The device operates from a regulated 4.75 V to 5.25 V supply and includes a propagation delay of 60 ns, according to the published SP485REP-L specifications. Its 8-pin plastic DIP package is intended for through-hole assembly and prototyping rather than compact automated surface-mount production. The -40 C to +85 C operating range provides useful environmental headroom for industrial control, instrumentation, and communications equipment.
Typical uses include RS-485 field buses, industrial sensor networks, building automation equipment, remote monitoring stations, and data-acquisition systems. The high receiver impedance is particularly useful when many nodes share the same two-wire bus. Compared with a 1/8 or 1/4 unit-load transceiver, the 1/10 unit-load rating provides lower bus loading, while the trade-off is that the exact replacement must still match supply voltage, driver and receiver ratings, enable logic, and DIP pin mapping.
Designers should verify the manufacturer's pinout and termination requirements before layout, and should use a proper RS-485 line network with controlled stub lengths. The DIP footprint requires through-hole clearances and adequate lead-bend spacing. Because the verified data does not include detailed absolute-maximum ratings, driver output levels, or full timing tables, those values should be obtained from the manufacturer datasheet before final release.
This page consolidates the verified 1/10 unit-load, impedance, voltage, delay, temperature, package, pricing-directory, and replacement information with application guidance and package-conscious comparisons. It distinguishes confirmed facts from parameters that still require datasheet confirmation, helping engineers shortlist the SP485REP-L without overlooking PCB or bus-compatibility constraints.
直接替换替代料： SP485REP-L ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： SP485REP-L （相同外形与封装尺寸） ——差异在于 Mounting Type, Package, Data Rate, Duplex, Protocol.
SP485REP
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
SP485R
✅ 直接替换 ⚠️ 规格未核验联系询价
查看数据手册 →SP485
✅ 直接替换联系询价
查看数据手册 →SP485E
✅ 直接替换 ⚠️ 规格未核验联系询价
查看数据手册 →SP485ECP
✅ 直接替换📋 参考替代料（不在目录中）
SP485REP-L 规格参数
| Product Type | Half-duplex RS-485/RS-422 transceiver |
| Receiver Unit Load | 1/10 unit load |
| Supported Transceivers per Line | More than 400 transceivers |
| Receiver Input Impedance | 150 kOhm typical |
| Supply Voltage Range | 4.75 V to 5.25 V |
| Propagation Delay | 60 ns |
| Minimum Operating Temperature | -40 C |
| Maximum Operating Temperature | +85 C |
| Duplex Configuration | Half-duplex |
| Supported Standards | RS-485 and RS-422 |
| 封装 | 8-pin plastic DIP |
| 安装类型 | Through-hole |
| Driver Configuration | 1/1 differential driver |
SP485REP-L 8-pin plastic dip 引脚配置指南
SP485REP-L（8-pin plastic dip 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： SP485REP-L.
请参阅 数据手册 以查看完整引脚配置。
典型应用
SP485REP-L 适用于 6 应用s: Industrial RS-485 Sensor Bus, Building Automation Controller, Remote Data-Acquisition System, Instrumentation and Test Equipment, LED Lighting Control Network, Telecommunications Remote Unit.
Industrial RS-485 Sensor Bus
The SP485REP-L fits industrial sensor and measurement networks where many field nodes share one twisted pair. Its 1/10 unit-load receiver and typical 150 kOhm input impedance allow more than 400 transceivers on a transmission line according to the manufacturer datasheet. Place the transceiver near the bus connector, route the differential pair as a controlled 120-ohm transmission line, and use the half-duplex enable interface to arbitrate transmit access. The main design benefit is reduced bus loading, while the tradeoff is the larger 8-pin through-hole footprint compared with a surface-mount transceiver.
推荐
Building Automation Controller
The SP485REP-L is suitable for building-automation controllers that connect HVAC units, lighting modules, access controls, and environmental sensors over an RS-485 backbone. Its 150 kOhm typical receiver input impedance and 1/10 unit load reduce the effect of multiple terminated nodes on the bus. The 4.75 V to 5.25 V operating range also matches regulated 5 V control hardware. Designers should preserve the standard half-duplex direction-control arrangement, avoid long unterminated stubs, and verify the transceiver's 60 ns propagation delay against the complete network timing budget.
推荐
Remote Data-Acquisition System
The SP485REP-L can connect a remote data-acquisition unit to sensors distributed across a production facility. Its more-than-400-node capability provides substantial capacity for densely populated measurement buses, while the 60 ns propagation delay supports moderate-rate half-duplex transfers. The device normally sits between the host serial interface and a protected RS-485 connector, with logic controlling receiver and driver enable states. For field cables, use twisted-pair wiring, common reference or isolation strategy appropriate to the installation, and surge protection selected for the actual cable length and environment.
推荐
Instrumentation and Test Equipment
The SP485REP-L is useful in laboratory and field instrumentation that exposes a high-impedance multipoint measurement bus through a legacy RS-485 connector. The low 1/10 unit-load receiver input helps preserve signal quality when several instruments share a cable, and the -40 C to +85 C operating range supports industrial environments. Its 8-pin plastic DIP package favors serviceable, through-hole instrument construction. Engineers should nevertheless check grounding, isolation, coax-to-RS-485 transition details, and connector surge requirements because these protections are not contained in the transceiver itself.
推荐
LED Lighting Control Network
The SP485REP-L can support addressable industrial LED-lighting controllers that distribute dimming, color, and enable commands over a wired RS-485 trunk. The 1/10 unit-load receiver allows numerous lighting nodes to share the same pair without heavily loading the driver, and the 60 ns propagation delay is useful for command-oriented networks rather than high-bandwidth streaming. A controller typically uses the driver during command transmission and the receiver for acknowledgements. Keep branch stubs short, terminate the trunk as specified, and provide local decoupling and protection at exposed cable connectors.
推荐
Telecommunications Remote Unit
The SP485REP-L is applicable to telecommunications remote monitoring units that connect alarm, power, and environmental subsystems over an RS-485 backplane. Its low receiver loading is valuable when many monitored interfaces converge on one bus, while half-duplex operation limits wiring to a single differential pair. The 4.75 V to 5.25 V supply supports conventional 5 V equipment, but a -40 C to +85 C range may not satisfy every outdoor installation. For such deployments, confirm the exact environmental rating, add isolation where ground offsets are possible, and apply standards-compliant surge protection at the line interface.
推荐
推荐产品汇总
工程参考数据： SP485REP-L ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | SP485REP | SP485R | SP485 | SP485E | SP485ECP |
|---|---|---|---|---|---|---|
| Brand | Exar Corporation | Exar Corporation | Exar Corporation | Exar Corporation | Exar Corporation | Exar Corporation |
| Package | 8-pin plastic DIP | 8-pin plastic DIP - same | 8-pin plastic DIP - same | 8-pin plastic DIP - same | 8-pin plastic DIP - same | 8-pin plastic DIP - same |
| Duplex Configuration | Half-duplex | Half-duplex | Half-duplex | Half-duplex | Half-duplex | Half-duplex |
关键差异点
- Lower receiver loading for dense multipoint buses （对比 SP485R)
- High receiver input impedance （对比 SP485)
- Large-node RS-485 capability in a through-hole package （对比 SP485E)
设计说明
Route the SP485REP-L differential pair as a controlled transmission line and keep branch stubs short. The 1/10 unit-load receiver reduces loading on the shared bus, but it does not correct poor topology. Keep the transceiver close to the connector, maintain a continuous ground reference where the installation permits, and place termination only at the physical ends of the trunk. Confirm the actual pin assignments from the manufacturer datasheet before committing the eight-pin DIP footprint.
The verified operating range is 4.75 V to 5.25 V, so the SP485REP-L requires a regulated 5 V rail within those limits. Place local supply decoupling close to the device and account for current drawn by the driver, receiver, and external bus-termination network. Do not substitute a wider nominal voltage description for the documented operating range; validate minimum and maximum rail conditions across temperature and cable loading.
Do not treat the more-than-400-node capability as permission for arbitrary cabling. Network capacity still depends on cable length, data rate, termination, topology, grounding, and transceiver timing. The published 60 ns propagation delay must be included in the end-to-end protocol budget, and the half-duplex direction-control logic must prevent bus contention. The SP485REP-L is not inherently isolated, so applications with large ground-potential differences need an external isolation strategy.
合规信息
The supplied search results do not provide explicit RoHS, REACH, lead-free, halogen-free, conflict-minerals, or AEC-Q100 statements. The -L ordering suffix and the 2009 Exar-format datasheet revision do not by themselves establish current compliance, so those statuses remain unknown.
