PCA9507 - I2C Bus Extender 3.3V-5V Level Shift | NXP
料号： PCA9507 ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $1.25 | $1.25 |
| 10 | $1.12 | $11.20 |
| 100 | $0.95 | $95.00 |
| 500 | $0.82 | $410.00 |
| 1,000 | $0.69 | $690.00 |
PCA9507 概述
A bus extender, also called an I2C buffer or bus repeater, is an interface IC that sits between a controller segment and a peripheral segment of a two-wire bus. Within the power-management-of-signals hierarchy (bus extender -> I2C buffer/repeater -> interface IC -> semiconductor), its role is to isolate bus capacitance and translate logic levels so that each segment can be optimized independently for drive strength and voltage.
Key features include bidirectional buffering of both SDA and SCL, allowing total bus capacitance to exceed the standard 400 pF single-segment limit by splitting it across segments. The built-in level shift permits a 3.3 V controller to talk directly to a 5 V device rail without discrete MOSFET translators. Support for 18 m of cable is roughly 40x the typical practical I2C length, enabled by the accelerator (active pull-up) circuitry that sharpens rising edges.
Architecturally, the PCA9507 uses a rise-time accelerator on both sides that sources current into the bus during low-to-high transitions, compensating for RC delay on long cables or heavy loads. This keeps duty cycle distortion low at the 400 kHz Fast-mode ceiling. Because it retains all I2C-bus operating modes during level shifts, multi-master and clock-stretching behavior is preserved.
Typical applications include HDMI DDC channel extension between source and display, long-reach SMBus backplanes in servers and telecom racks, and I2C fan-out in industrial control cabinets where sensors sit meters from the master.
Design consideration: allocate adequate pull-up resistance per segment - the accelerator assists edges but does not replace pull-ups; verify segment capacitance budget separately on each side of the buffer.
This page synthesizes distributor pricing, drop-in alternatives, design notes, and application guidance not found in a single manufacturer datasheet.
直接替换替代料： PCA9507 ——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： PCA9507 （相同外形与封装尺寸） ——差异在于 Function, Package, Number of Channels, RoHS Status, Direction Control.
快速对比工具——选择替代料号进行并排对比：
PCA9517D,118
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
PCA9617A
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
PCA9511AD,118
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$0.96 / 个
查看数据手册 →PCA9510ADP,118
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
联系询价
查看数据手册 →PCA9515AD,118
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
PCA9507 规格参数
| 功能 | 2-wire serial bus extender (I2C buffer/level shifter) |
| Applications | HDMI DDC, I2C-bus, SMBus |
| Level Shift | 3.3 V to 5 V |
| Maximum Bus Length | 18 m |
| 数据速率 | 400 kHz |
| Number of Channels | 1 |
| 封装 | 8-SO (SOIC-8) |
| 安装类型 | Surface Mount |
| 引脚数 | 8 |
| Rise Time Accelerator | Yes (bidirectional SDA/SCL accelerator) |
PCA9507 8-so (soic-8) 引脚配置指南
PCA9507（8-so (soic-8) 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： PCA9507.
请参阅 数据手册 以查看完整引脚配置。
典型应用
PCA9507 适用于 6 应用s: HDMI DDC Channel Extension, Long-Reach SMBus Backplanes, Industrial I2C Fan-Out in Control Cabinets, Display and Panel Control Interfaces, Battery Management and Hot-Swap Monitoring Buses, Networking Equipment Management Buses.
HDMI DDC Channel Extension
In HDMI source-to-sink paths, the DDC channel carries EDID and HDCP authentication data over I2C at 100-400 kHz. The PCA9507 fits this application directly because the NXP datasheet explicitly names HDMI DDC as a target bus, and its 3.3 V to 5 V level shift bridges the typical source-side 3.3 V and sink-side 5 V domains transparently. Placed in the DDC SDA and SCL path near the connector, its bidirectional accelerator sharpens rising edges degraded by cable capacitance, and its 18 m extension rating comfortably covers long in-wall or rack HDMI runs. The trade-off is added propagation delay, negligible at DDC speeds but worth confirming in HDCP timing margins.
推荐
Long-Reach SMBus Backplanes
Server, telecom, and power-shelf backplanes use SMBus to monitor PSU, fan, and hot-swap controllers, and bus lengths of several meters are common between a BMC and far-end modules. The PCA9507 suits this because it retains SMBus operating modes during buffering and its 18 m extension capability exceeds typical rack backplane runs with margin. Its rise-time accelerator compensates for the heavy capacitance of distributed monitoring loads, while the 400 kHz rating covers standard SMBus 100 kHz operation with headroom. Designers should size pull-ups per segment and verify that SMBus clock low extend behavior passes through the buffer as expected in multi-slave trees.
推荐
Industrial I2C Fan-Out in Control Cabinets
Industrial control cabinets often place PLC I/O, sensors, and EEPROM configuration devices meters away from the master controller, violating the capacitance-limited reach of a direct I2C bus. The PCA9507 addresses this by isolating capacitance into two segments and actively accelerating edges, enabling 18 m runs through cable trays at 400 kHz. Its 3.3 V to 5 V level shift allows modern 3.3 V microcontrollers to talk to legacy 5 V sensors and serial EEPROMs without discrete translators. Industrial environments should route the buffered bus away from motor drives and contactor switching noise; the accelerator's active pull-up improves noise margin on falling-edge-induced glitches at these distances.
推荐
Display and Panel Control Interfaces
Large displays and digital signage panels distribute I2C control buses across backlight, timing, and scaler boards separated by tens of centimeters to meters of flex and cable. The PCA9507 fits because it preserves all I2C operating modes during level shift, keeps EDID and control traffic reliable across board-to-board cabling, and supports the 5 V rails common on panel power boards from 3.3 V scaler chipsets. Its single-channel buffering of both SDA and SCL is sufficient for one control tree; multiple display buses each need one PCA9507. Designers should decouple the buffer supply locally and verify total segment capacitance stays within I2C limits per segment.
推荐
Battery Management and Hot-Swap Monitoring Buses
Battery packs and hot-swap shelves serialize SMBus monitoring across cell boards and modules spaced by cable harnesses, creating long, capacitive buses. The PCA9507 is appropriate because its 18 m extension capacity and edge acceleration keep SMBus traffic reliable across harness runs, and its 3.3 V to 5 V translation interfaces 3.3 V gauge MCUs with 5 V SMBus battery modules. Because the accelerator sources current on rising edges, designers must validate that Smart Battery protocol timing and any sleep/wake signaling across the buffer behave correctly; the family datasheets provide application sections covering hot-insertion behavior and recommended pull-up values for each segment.
推荐
Networking Equipment Management Buses
Switches, routers, and optical transport gear use I2C/SMBus management buses spanning a chassis, connecting a management MCU to optical modules, temperature sensors, and power monitors distributed across several cards. The PCA9507 suits this topology because the 18 m rating exceeds chassis-scale wire runs, the 400 kHz rate supports fast polling, and level shifting between 3.3 V management planes and 5 V optics or fan trays removes discrete translation stages. Its bidirectional buffering preserves multi-master arbitration used by redundant management controllers. Segment each card or shelf with its own buffer rather than one buffer per chassis, and budget pull-up resistance per segment per NXP application guidance.
推荐
推荐产品汇总
工程参考数据： PCA9507 ——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 | PCA9517D,118 | PCA9617A | TCA9517DR |
|---|---|---|---|---|
| Package | SOIC-8 (8-SO) | SOIC-8 - same | SOIC-8 - same | SOIC-8 - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | Texas Instruments |
| Level Shift | 3.3 V to 5 V | 1.0 V to 5.5 V (wider) | 2.3 V/3.3 V to 5 V selectable | 1.65 V to 5.5 V |
| Maximum Data Rate | 400 kHz | 400 kHz | 1 MHz (Fm+) | 400 kHz |
| Rise-Time Accelerator | Yes | Yes | Yes (adjustable) | Yes (accelerator outputs) |
| HDMI DDC Optimization | Yes (primary target) | General-purpose | General-purpose | General-purpose |
关键差异点
- HDMI DDC-optimized bus extension （对比 PCA9517D,118)
- Longer bus reach than non-accelerated buffers （对比 PCA9515AD,118)
- Wider low-voltage support in the alternative （对比 TCA9517DR)
设计说明
Place the PCA9507 close to the cable or backplane connector it serves so that the long, capacitive segment sits on the accelerator-assisted side. Decouple the supply with a 100 nF ceramic capacitor directly at the VCC pin, plus a 1 uF bulk capacitor nearby. Keep SDA/SCL traces on the short segment as short and direct as possible; the long segment's edge shaping depends on the buffer seeing clean, low-capacitance connections on the controller side.
Pull-up resistor values must be calculated per segment, not globally. Each side of the PCA9507 forms an independent RC network: choose pull-ups so each segment meets I2C rise-time requirements at 400 kHz given that segment's capacitance. The internal accelerator sources additional current on rising edges but does not replace pull-ups. Estimated guideline: for a 3 m cable segment with roughly 300 pF capacitance, start around 1-2 kiloohm pull-ups and verify rise time on the bench, since the accelerator's dynamic drive changes effective edge behavior.
A common failure is assuming the buffer removes all bus-length limits: the 18 m rating assumes proper per-segment capacitance budgeting and termination. Do not daisy-chain multiple buffers without reviewing segment loading, and remember that level shift direction is fixed at 3.3 V to 5 V - connecting the sides backwards will prevent correct translation. Also verify HDMI HDCP timing with the added buffer delay in the DDC path before tape-out of display designs.
On long cable runs, route SDA and SCL as a modest-impedance pair with ground reference, and avoid running them adjacent to switching power or motor drive harnesses. The rise-time accelerator sharpens edges, which is beneficial for timing but means fast edges can couple into neighboring conductors; maintain spacing or add guard ground on flat-cable implementations. Scope both edges at the far-end device under full load to confirm duty cycle and noise margin.
合规信息
Compliance data was not present in the provided web data. NXP orderable variant PCA9507D,118 suggests standard NXP lead-free/RoHS ordering suffix; confirm on the official NXP product page.
