P82B715TD - 2-Bit 400 kHz I2C Bus Extender | NXP
料号： P82B715TD ✗ 停产P82B715TD 概述
An I2C-bus extender is a specialized interface IC within the broader bus-buffer and signal-repeater hierarchy. It sits between a host controller and a remote I2C segment, isolates the two sides electrically, and allows slow or heavily loaded bus sections to operate more reliably. Unlike a general-purpose unidirectional logic buffer, the P82B715 supports bidirectional clock and data signaling, making it suitable for I2C and derivative bus systems where both sides may initiate or acknowledge a transfer.
The principal operating specifications are a 3 V to 12 V supply range, a 400 kHz maximum bus frequency, bidirectional operation on both buffered channels, and an 8-lead plastic small-outline package. The NXP product page identifies the package as SO8 with 8 leads on a 1.27 mm pitch and a body measuring 4.9 mm by 3.9 mm by 1.75 mm. These package dimensions allow the extender to be placed close to a bus segment while preserving a conventional SOIC-8 land pattern.
The P82B715 is a bipolar integrated circuit, and its buffer arrangement uses internal series resistance to isolate the two bus sides. The resulting offset between a buffered input and its corresponding bus output depends on current flow, which makes system-level timing, pull-up selection, and wiring length important design variables. The enable pins allow the buffered sections to be disconnected when the device is not required, supporting controlled power management in multi-segment systems.
Typical applications include extending I2C sensors, extending SMBus devices on industrial or telecommunications equipment, isolating cable capacitance from a controller, and supporting low-speed bus runs where additional loading would otherwise degrade rise time. The extender is also useful where a peripheral group must be placed behind connectors, test points, or long wiring while the main controller continues to operate from a separate bus segment.
Designers should verify pull-up placement, enable polarity, maximum cable capacitance, operating frequency, and logic-level compatibility against the manufacturer datasheet before release. Because the P82B715 buffers rather than regenerates the bus waveform into an unrelated signal path, trace geometry, connector stubs, and the location of pull-up resistors can materially affect signal integrity. The buffered side should be treated as a distinct I2C segment with its own appropriate pull-up network.
This product page consolidates the verified NXP and distributor data, separates manufacturer specifications from unavailable pricing fields, identifies genuine same-family drop-in alternatives, and adds application guidance and engineering checks that are not consolidated in a distributor catalog entry.
直接替换替代料： P82B715TD ——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： P82B715TD （相同外形与封装尺寸） ——差异在于 Product Type, Architecture, Package.
P82B715TD 规格参数
| Product Type | 2-bit bidirectional I2C-bus and SMBus extender |
| Manufacturer | NXP Semiconductors |
| Supply Voltage Range | 3 V to 12 V |
| Maximum Bus Frequency | 400 kHz |
| Buffered Channels | 2 channels: SCL and SDA |
| Bus Direction | Bidirectional |
| Supported Bus | I2C-bus and derivative SMBus systems |
| Process Technology | Bipolar integrated circuit |
| Package Type | SO8 plastic small-outline package |
| Lead Count | 8 leads |
| Lead Pitch | 1.27 mm |
| Package Body Length | 4.9 mm |
| Package Body Width | 3.9 mm |
| Package Body Height | 1.75 mm |
| 安装类型 | Surface mount |
| Internal Bus Resistance | 30 ohm |
| Enable Control | Enable pins present |
P82B715TD 引脚配置
| 引脚 1 | SCL — Clock input/output on the bus side |
| 引脚 2 | SDA — Data input/output on the bus side |
| 引脚 3 | GND — Ground connection |
| 引脚 4 | EN — Enable input for the buffered bus side |
| 引脚 5 | EN — Enable input for the buffered bus side |
| 引脚 6 | GND — Ground connection |
| 引脚 7 | SDA — Data input/output on the buffered side |
| 引脚 8 | SCL — Clock input/output on the buffered side |
典型应用
P82B715TD 适用于 6 应用s: I2C Sensor Bus Extension, Industrial SMBus Segmentation, Long-Distance I2C Cable Support, Communication Equipment Backplane Isolation, Test and Measurement Module, Low-Power Bus Power Management.
I2C Sensor Bus Extension
The P82B715TD fits sensor-heavy I2C designs because it buffers both SCL and SDA while operating across a 3 V to 12 V supply range at up to 400 kHz. Place the extender between a controller and a remote group of temperature, pressure, or acceleration sensors so the remote segment does not load the main bus directly. Its two bidirectional channels retain normal I2C clocking and acknowledgment behavior across the buffered boundary. The benefit is improved practical bus separation for longer wiring or added peripheral capacitance, while the trade-off is that the buffered section must retain suitable pull-ups and acceptable rise time. Confirm logic thresholds and cable capacitance against the NXP datasheet before deploying the part with 400 kHz traffic.
推荐
Industrial SMBus Segmentation
The P82B715TD is useful for segmenting SMBus systems in industrial equipment where a cable, connector, or long harness separates a controller from remote devices. Its bidirectional 400 kHz architecture handles both clock and data, while the 3 V to 12 V operating range supports both 5 V and 9 V industrial bus environments when signal-level compatibility is otherwise satisfied. Installing the extender at the board boundary can isolate the remote segment from the host bus and reduce accumulated loading. Designers should treat the remote side as a separate I2C branch, evaluate pull-up placement, and confirm that the complete bus remains within the 400 kHz specification.
推荐
Long-Distance I2C Cable Support
The P82B715TD can extend the practical separation between I2C devices by buffering both clock and data rather than allowing the remote capacitance to load the controller directly. The 400 kHz limit and bidirectional SCL/SDA channels suit standard I2C cable-extension arrangements, especially where connectors and test points add capacitance. Position the device near the cable interface, use an appropriate pull-up network on each side, and minimize unnecessary stubs. The extender does not remove all rise-time limitations, so cable length, connector capacitance, pull-up strength, and the target operating frequency must be evaluated together before sign-off.
推荐
Communication Equipment Backplane Isolation
In communication equipment, the P82B715TD can separate a controller-side I2C management bus from a remote card, connector, or test assembly. Its two bidirectional channels preserve SDA and SCL communication through the isolation boundary, and the 8-lead SOIC package supports placement near the interface connector. The bipolar implementation and internal 30 ohm series resistance provide the defined bus-segment behavior described in the NXP datasheet. Because the device adds a series voltage offset under current flow, engineers should validate signal levels at the far endpoint and avoid interpreting the buffered side as an unregulated direct continuation of the original bus.
推荐
Test and Measurement Module
The P82B715TD is appropriate for test and measurement modules that place remote sensors, converters, or acquisition components behind cables or front-panel connectors. Buffering SCL and SDA can prevent remote capacitance from degrading the local control bus, while the 400 kHz operating ceiling supports standard I2C transfer rates. The SOIC-8 package is convenient for compact instrument boards and allows straightforward decoupling and routing near the connector. Because no connector or cable model is specified in the verified data, engineers must validate timing with the actual harness, pull-up values, and worst-case peripheral loading rather than relying on nominal bus frequency alone.
推荐
Low-Power Bus Power Management
The P82B715TD supports power-management designs that temporarily disconnect a remote I2C segment through its enable controls. The buffered SCL and SDA paths maintain bidirectional communication when enabled, while the enable pins permit a system to isolate inactive or unpowered branch devices. This is valuable in battery-powered modules, test fixtures, and equipment with several bus domains. Designers must verify the exact enable polarity, inactive-state behavior, supply sequencing, and bus levels from the official datasheet. The component should not be considered sufficient by itself for power-off isolation unless the remote devices and pull-up network are also designed to prevent back-powering.
推荐
推荐产品汇总
工程参考数据： P82B715TD ——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 | P82B715D | P82B715DR |
|---|---|---|---|
| Package | SOIC-8 | SOIC-8 | SOIC-8 |
| Brand | NXP Semiconductors | Texas Instruments | NXP Semiconductors |
| Product Function | 2-bit bidirectional I2C-bus extender | 2-bit bidirectional I2C-bus extender | 2-bit bidirectional I2C-bus extender |
| Supply Voltage Range | 3 V to 12 V | 3 V to 12 V | 3 V to 12 V |
| Maximum Bus Frequency | 400 kHz | 400 kHz | 400 kHz |
| Buffered Channels | 2 channels for SCL and SDA | 2 channels for SCL and SDA | 2 channels for SCL and SDA |
| Bus Direction | Bidirectional | Bidirectional | Bidirectional |
| Process Technology | Bipolar integrated circuit | Bipolar integrated circuit | Bipolar integrated circuit |
| Supported Bus | I2C-bus and derivative SMBus systems | I2C-bus and derivative SMBus systems | I2C-bus and derivative SMBus systems |
关键差异点
- Matches the verified 2-bit, 400 kHz P82B715 extender function （对比 P82B715D)
- Preserves an existing NXP-qualified source path （对比 P82B715D)
- Uses the established 8-pin small-outline footprint （对比 P82B715DR)
设计说明
Treat the P82B715TD as a buffered bus boundary rather than a transparent wire. The NXP datasheet states that the buffered output does not amplify current flowing back into the bus and that the voltage offset between corresponding SDA or SCL nodes depends on current through the internal 30 ohm resistor. Validate high and low levels at the remote endpoint, account for pull-up current in worst-case loading, and use scope measurements at the actual connector and load points.
Place the P82B715TD near the physical boundary of the remote I2C segment and keep the controller-side and remote-side routing paths visually distinct. Provide normal, short supply and ground connections, use a solid ground plane, and avoid routing either clock or data beside a noisy switching node. Pull-up placement must follow the manufacturer application guidance for the selected bus topology; incorrectly locating a pull-up can defeat the intended segment isolation.
Do not assume that the nominal 400 kHz rating guarantees reliable operation over an arbitrary cable length. Bus capacitance, connector stubs, pull-up resistance, clock stretching, peripheral count, and propagation delay can all reduce usable bandwidth. Validate worst-case rise and fall times with the final harness and peripheral loading, confirm enable polarity, and ensure that an inactive or unpowered remote device cannot back-power the buffered bus through its input or output structures.
合规信息
The supplied manufacturer and distributor snippets do not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. No compliance claim has been inferred.
