PCA9515AP - 2-Channel 400kHz I2C Repeater | TI
部品番号: PCA9515AP ✓ 生産中PCA9515AP 概要
An I2C repeater is a bidirectional bus buffer that regenerates a bus signal and separates it into two bus segments. It belongs to the interface IC hierarchy, where I2C and SMBus repeaters support communication among controllers, peripherals, sensors, and embedded processors. Unlike a unidirectional level translator, this device detects and forwards activity in either direction, allowing each side of the bus to retain its own pull-up network.
The PCA9515A family provides two identical bidirectional open-drain buffers, an active-high enable input with an internal pull-up, and 5.5 V-tolerant bus and enable inputs. Mixed-mode signal operation is supported, while the open-drain I2C structure maintains wired-AND bus behavior. The verified distributor listing identifies the PCA9515AP as a 400 kHz, two-channel buffer in an 8-pin PDIP package.
The repeater is built around BiCMOS interface circuitry intended to preserve the open-drain signaling used by I2C and SMBus. Because both sides communicate bidirectionally, bus capacitance, pull-up strength, rise time, and timing margins must be evaluated separately for each segment. The enable input is particularly useful during system reset because it can isolate a misbehaving peripheral, but its state should not change during an active I2C transfer.
Typical uses include isolating a high-capacitance I2C bus, connecting sensors or EEPROMs to a remote bus segment, buffering a processor I2C controller, supporting SMBus power-management hardware, and isolating power domains whose logic levels remain compatible with the repeater. It can also help separate a bus into shorter segments when capacitive loading or timing margins become problematic.
The primary design consideration is that the PCA9515AP is not a general-purpose bidirectional level shifter. Its supply range is 2.3 V to 3.6 V, and the enabled repeater must maintain compatible logic levels across both bus segments. External pull-up resistors should be placed close to each bus segment, with values selected from the actual capacitance and required rise time rather than copied blindly.
This page consolidates verified distributor specifications, the official manufacturer datasheet, package details, application guidance, and honest replacement analysis. It also distinguishes verified drop-in interchangeability from mechanically similar parts that would require PCB changes, helping engineers compare alternatives without treating a same-family option as automatically safe to substitute.
ドロップイン代替品: PCA9515AP — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
PCA9515DP
✅ ドロップイン📋 参考代替品（カタログ未掲載）
PCA9515AP 仕様
| Product Type | Dual bidirectional I2C bus and SMBus repeater |
| Number of Channels | 2 channels |
| Maximum Bus Frequency | 400 kHz |
| Supply Voltage Range | 2.3 V to 3.6 V |
| I2C and Enable Input Tolerance | 5.5 V |
| Buffer Architecture | Bidirectional open-drain |
| Bus Compatibility | I2C and SMBus |
| Enable Polarity | Active-high |
| Enable Input | Internal pull-up |
| Process Technology | BiCMOS |
| Mixed-Mode Operation | Supported |
| Lockup-Free Operation | Supported |
| パッケージ | 8-pin PDIP |
| 実装タイプ | Through-hole |
| RoHS ステータス | Compliant |
PCA9515AP ピン構成
| ピン 1 | EN — Active-high repeater-enable input with an internal pull-up |
| ピン 2 | VCC — Device supply voltage input |
| ピン 3 | SCL1 — Serial clock side of bidirectional channel 1 |
| ピン 4 | SDA1 — Serial data side of bidirectional channel 1 |
| ピン 5 | SDA2 — Serial data side of bidirectional channel 2 |
| ピン 6 | SCL2 — Serial clock side of bidirectional channel 2 |
| ピン 7 | GND — Ground connection |
| ピン 8 | NC — Not connected |
主な用途
PCA9515AP の用途: 6 件s: High-Capacitance I2C Bus Segmentation, I2C Sensor Hub Isolation, SMBus Power-Management Segmentation, Embedded Processor I2C Port Buffering, Remote Sensor and EEPROM Bus, Mixed-Voltage Peripheral Isolation.
High-Capacitance I2C Bus Segmentation
The PCA9515AP is useful when an I2C bus reaches a capacitance or timing limit because it splits the network into two shorter, independently pulled-up segments. Its two bidirectional open-drain channels operate up to 400 kHz, allowing the controller to communicate with devices on either side of the repeater without redrawing the entire bus. Each channel adds propagation delay and local capacitance, so the design should verify rise time and timing margin at the intended frequency. This makes the device a practical solution for populated backplanes, long harnesses, or clustered sensors.
おすすめ
I2C Sensor Hub Isolation
The PCA9515AP can isolate a group of sensors from a host controller so an imperfect peripheral is less likely to hold the main bus low. Each of the two channels provides bidirectional open-drain buffering at up to 400 kHz, while the active-high enable input offers a controlled way to keep a segment inactive during startup. The isolation boundary should be enabled only after power stabilization and sensor initialization, because changing EN during a transfer can hang the bus. This arrangement improves fault containment without requiring separate I2C controllers.
おすすめ
SMBus Power-Management Segmentation
The PCA9515AP is compatible with SMBus signaling and can divide a power-management bus into manageable segments. Its bidirectional open-drain channels permit host transactions and device responses to pass through the repeater at rates up to 400 kHz, subject to the actual SMBus timing and pull-up network. The 2.3 V to 3.6 V supply range suits low-voltage systems, while the 5.5 V-tolerant inputs help accommodate mixed logic levels. Enable control is useful for staged startup of power-management peripherals, provided it remains stable during transactions.
おすすめ
Embedded Processor I2C Port Buffering
The PCA9515AP can buffer a processor's I2C port when its external pull-up network cannot reliably drive the intended load. Both channels preserve the bidirectional, open-drain signaling expected by I2C peripherals and support operation up to 400 kHz. This allows a controller to reach a remote bus section without changing the processor's pin multiplexing or firmware. Engineers should place separate pull-up resistors on each side, verify the resulting rise time, and confirm that the added repeater delay remains within the controller's timing budget.
おすすめ
Remote Sensor and EEPROM Bus
The PCA9515AP can extend an I2C connection to a remote sensor, EEPROM, or other low-speed peripheral when wiring distance would otherwise increase bus capacitance. The two-channel structure can isolate the remote segment from the local controller bus while maintaining bidirectional command and response traffic. Because I2C is open-drain, the remote side needs its own appropriately sized pull-up network and return path. The 400 kHz capability allows operation above standard 100 kHz mode, but rise time and propagation delay should be evaluated using the actual cable and peripheral loading.
おすすめ
Mixed-Voltage Peripheral Isolation
The PCA9515AP can support mixed-mode I2C connections because its bus and enable inputs are tolerant of signals up to 5.5 V, while its own supply operates from 2.3 V to 3.6 V. This allows a 3.3 V repeater to sit between compatible open-drain bus segments that may include higher-level signaling. It does not by itself translate every possible voltage combination, so both sides must remain compatible with the repeater's logic thresholds. The enable input can further isolate a segment during reset, but it should not be changed while a bus transfer is active.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: PCA9515AP — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | PCA9515DP |
|---|---|---|
| Manufacturer | Texas Instruments | NXP Semiconductors |
| Package | PDIP-8 | PDIP-8 |
| Product Type | Dual bidirectional I2C and SMBus repeater | I2C repeater |
主な差別化要因
- Verified 400 kHz dual-channel operation （vs PCA9515DP)
- Documented active-high enable control （vs PCA9515DP)
- Documented 5.5 V-tolerant bus inputs （vs PCA9515DP)
設計ノート
Do not toggle the active-high enable input during an I2C transaction. The Texas Instruments datasheet warns that disabling the repeater during a bus operation can hang the bus, while enabling it partway through a cycle can confuse connected I2C devices. Define EN in the reset and power-sequencing logic so it remains stable from before the first bus transfer until the system is fully powered down.
Give each side of the repeater its own pull-up network rather than sharing one pull-up group across the isolation boundary. Place the pull-up capacitors close to the devices driving each open-drain segment and keep the separated traces away from unrelated noisy circuitry. Because both channels are bidirectional, check rise time, bus capacitance, and propagation delay for the complete path from the controller through the repeater to the farthest peripheral.
Keep the PCA9515AP supply within its verified 2.3 V to 3.6 V operating range and decouple VCC locally. The 5.5 V input tolerance applies to the I2C and enable inputs; it does not permit the supply pin to exceed the operating range. Place the bypass capacitor close to the supply and ground pins, and verify the power-up relationship between VCC, EN, pull-ups, and connected peripherals to avoid unintended bus activity during reset.
コンプライアンス情報
The verified Ampheo component listing identifies PCA9515AP as RoHS compliant. No verified REACH, lead-free, halogen-free, conflict-minerals, or automotive-qualification statement was supplied.