SP485REP-L - 1/10 Unit Load RS-485 Transceiver | Exar
MPN： SP485REP-L ✓ 啟用中SP485REP-L 概覽
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.
直接替換替代品，適用於 SP485REP-L — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： SP485REP-L （相同外形與佔位） — 差異在於 Mounting Type, Package, Data Rate, Duplex, Protocol.
SP485REP
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
SP485R
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →SP485
✅ 直接替換聯絡詢價
查看資料表 →SP485E
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →SP485ECP
✅ 直接替換📋 參考替代品（不在目錄中）
SP485REP-L 規格
| 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 |
| 封裝 | 8-pin plastic DIP |
| 安裝類型 | Through-hole |
| Driver Configuration | 1/1 differential driver |
SP485REP-L 8-pin plastic dip 腳位配置指南
SP485REP-L（8-pin plastic dip 封裝）的腳位配置。 腳位編號、功能與連接圖定義於製造商資料手冊中。請參閱該手冊以取得確切的封裝尺寸與焊接指引。
無詳細腳位定義資料： SP485REP-L.
請參閱 資料表 以查看完整腳位配置。
典型應用
SP485REP-L 適用於 6 應用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.
推薦
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.
推薦
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.
推薦
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.
推薦
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.
推薦
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.
推薦
推薦產品摘要
工程參考資料，適用於 SP485REP-L — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | 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 |
主要差異化特點
- Lower receiver loading for dense multipoint buses (對比SP485R)
- High receiver input impedance (對比SP485)
- Large-node RS-485 capability in a through-hole package (對比SP485E)
設計說明
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.
合規資訊
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.
