PCA9515APW - 2-Channel 400kHz I2C/SMBus Repeater | TI
N.º de pieza: PCA9515APW ✓ ActivoPCA9515APW Descripción general
An I2C or SMBus repeater is a bus-interface IC that connects two sections of a serial bus while allowing signals to travel in both directions. Unlike a unidirectional level shifter or a directional transceiver, the PCA9515A provides independent bidirectional channels for SDA and SCL. It supports Standard Mode and Fast Mode devices, allowing a system to extend an I2C bus, isolate a problematic device during startup, or add another bus branch without loading the original bus directly.
The PCA9515A includes an active-high enable input with an internal pullup. The enable function can be used to isolate a malfunctioning or poorly behaved slave during power-up reset, but the enable state should not change during an I2C operation because disabling the repeater during a bus cycle can hang the bus. Open-drain I2C I/O pins support mixed-mode operation and powered-off high-impedance behavior, helping the device remain compatible with system-level bus isolation requirements.
With a 2.3 V to 3.6 V operating range and 400 kHz bus capability, the PCA9515APW is appropriate for embedded systems, sensor networks, industrial controllers, communication equipment, and compact consumer electronics. The 8-pin TSSOP package keeps the design compact while providing separate input and output-side connections for each bidirectional channel.
A key design consideration is the enable pin. Its internal pullup defaults the repeater to the enabled state, but a system controller can use the input for reset sequencing or fault isolation. Review the datasheet pin descriptions and application examples before assigning tracks, especially when the two sides of the repeater use different pullup networks or bus voltage domains.
This page combines manufacturer specifications, package and pinout information, drop-in replacement assessment, application guidance, and practical interface-design notes for engineers evaluating PCA9515APW implementations.
Alternativas directas para PCA9515APW — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
No hay alternativas directas disponibles para este producto.
Solicitar alternativasPCA9515APW Especificaciones
| Product Type | Dual bidirectional I2C bus and SMBus repeater |
| Number of Channels | 2 channels |
| Tensión de alimentación de funcionamiento | 2.3 V to 3.6 V |
| Maximum Bus Frequency | 400 kHz |
| I2C Compatibility | I2C and SMBus |
| Bus Architecture | Bidirectional open-drain buffer |
| Enable Input | Active-high EN with internal pullup |
| I2C I/O Voltage Tolerance | 5.5 V tolerant |
| Powered-Off I2C Pins | High impedance |
| Signal Mode Support | Standard Mode and Fast Mode |
| Multiple Master Support | Supported |
| Mixed-Mode Signal Operation | Supported |
| Encapsulado | 8-pin TSSOP (PW) |
| Tipo de montaje | Surface mount |
| ESD Classification | Class II |
| Latch-Up Performance | Exceeds 100 mA per JESD 78 |
Configuración de pines de PCA9515APW
| Pin 1 | EN — Active-high repeater-enable input with internal pullup |
| Pin 2 | SCL1 — Bidirectional clock input/output for channel 1 |
| Pin 3 | SDA1 — Bidirectional data input/output for channel 1 |
| Pin 4 | GND — Ground |
| Pin 5 | VCC — Positive supply voltage |
| Pin 6 | SCL2 — Bidirectional clock input/output for channel 2 |
| Pin 7 | SDA2 — Bidirectional data input/output for channel 2 |
| Pin 8 | NC — Not connected (per datasheet) |
Aplicaciones típicas
PCA9515APW es adecuado para 6 aplicacións: I2C Bus Extension, SMBus Segmentation, Sensor Network Conditioning, Embedded Control Interface, Communication Equipment, Power-Sequenced Peripheral Isolation.
I2C Bus Extension
The PCA9515APW fits between an upstream controller and a downstream I2C branch when interconnect capacitance would otherwise reduce bus reliability. Its two bidirectional open-drain channels support SDA and SCL without changing the wired-AND signaling convention, while the 400 kHz rating accommodates Standard Mode and Fast Mode devices. The 2.3 V to 3.6 V operating range suits embedded systems running from low-voltage rails. In practice, bus extension remains sensitive to pullup resistance, cable capacitance, rise-time margin, and the capacitance supported by the connected devices, so the repeater should be placed where the two bus sections can be analyzed independently.
Recomendado
SMBus Segmentation
The PCA9515APW can divide a larger SMBus system into separately buffered segments, helping prevent added bus loading from affecting the controller directly. Its bidirectional open-drain channels are compatible with the SMBus signaling style, and the 400 kHz maximum operating frequency provides margin for Fast Mode-compatible devices. The active-high EN input with internal pullup can support controlled isolation during startup. Designers should avoid changing EN during a bus transaction, because doing so can interrupt a byte or leave the bus stuck, and should confirm that downstream pullups and powered-off behavior match the system fault model.
Recomendado
Sensor Network Conditioning
The PCA9515APW is useful when a group of remote sensors creates enough bus capacitance to degrade an I2C controller's edge performance. Placing the repeater close to the sensor branch isolates that load while retaining two-way SDA and SCL communication. Its 400 kHz capability supports many Fast Mode sensor combinations, while the compact 8-pin TSSOP package simplifies routing in space-constrained embedded hardware. Pullup placement, trace length, connector capacitance, and the number of sensors remain critical; adding a repeater does not remove the need for a compliant bus rise time under worst-case loading.
Recomendado
Embedded Control Interface
The PCA9515APW fits embedded control boards that need a dedicated isolation point between a microcontroller and an I2C peripheral subsystem. The 2.3 V to 3.6 V supply range aligns with common low-voltage MCU rails, and the two open-drain channels allow the downstream section to be disconnected logically through EN. This is especially helpful during reset or peripheral brownout conditions. Keep the enable net under defined control states, verify that every connected device supports the bus voltage, and use the manufacturer's application guidance when the downstream section may remain powered while the repeater is disabled.
Recomendado
Communication Equipment
The PCA9515APW can segment an I2C management bus in communication equipment where configuration devices, status registers, or temperature sensors are distributed across a board. The 400 kHz rating supports typical management-bus traffic, while the bidirectional open-drain channels preserve normal I2C behavior on both sides of the device. Its small TSSOP footprint leaves routing space for signal and power integrity work. For equipment with long internal interconnects, place the repeater at the load boundary, maintain appropriate pullups on each bus section, and validate timing across temperature and the complete peripheral population.
Recomendado
Power-Sequenced Peripheral Isolation
The PCA9515APW supports designs that need a controlled connection point between a host bus and a peripheral bank with uncertain startup behavior. Its active-high EN input includes an internal pullup, allowing the default state to remain enabled while a controller can override the connection for reset sequencing. The manufacturer specifically notes that EN should not change during an I2C operation, so firmware and hardware must avoid toggling it while transfers are active. The 2.3 V to 3.6 V supply range also allows the repeater to operate from the same low-voltage rail as many modern sensor and interface ICs.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para PCA9515APW — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto |
|---|---|
| Package | 8-pin TSSOP (PW) |
| Brand | Texas Instruments |
| Device Function | Dual bidirectional I2C/SMBus repeater |
| Number of Channels | 2 channels |
| Operating Supply Voltage | 2.3 V to 3.6 V |
| Maximum Bus Frequency | 400 kHz |
| Enable Input | Active-high with internal pullup |
| I2C I/O Tolerance | 5.5 V tolerant |
| Bus Architecture | Bidirectional open-drain |
| Powered-Off I2C Pins | High impedance |
Diferenciadores clave
- Bidirectional two-channel integration in a compact package (frente a PCA9515ADP,118)
- Active-high enable with integrated default pullup (frente a PCA9515BDGKR)
- 400 kHz operation with powered-off high-impedance behavior (frente a PCA9500PW)
Notas de diseño
Place the PCA9515APW near the load boundary of the extended I2C section so that long traces, connectors, and remote-device capacitance remain on the downstream side. Keep the upstream and downstream pullup networks sized for their respective loads. The open-drain channels require pullup resistors for proper high-level rise time, and the 400 kHz rating does not guarantee usable bus length when capacitance is excessive.
Do not change EN during an active I2C transfer. 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 devices. Define EN at reset so it has a stable state before communication begins, and account for the internal pullup when designing an external override circuit.
Route SDA1 and SCL1 toward the host-side connector and SDA2 and SCL2 toward the extended-device section, following the package pin assignments in the datasheet. Provide a continuous ground reference, avoid long parallel runs where unnecessary, and keep the EN trace away from high-current switching edges. Verify that the exposed routing, connector, and device capacitances support the intended rise time and 400 kHz operating rate.
Decouple VCC locally with the capacitance and placement specified by the manufacturer application guidance. Because the PCA9515APW operates from 2.3 V to 3.6 V, its supply must remain within that range even when the I2C lines use 5.5 V-tolerant signaling. Analyze the case where one bus side is powered while the repeater is disabled or unpowered, particularly when downstream pullups continue driving the isolated section.
Información de cumplimiento
The Texas Instruments product materials identify lock-up performance exceeding 100 mA per JESD 78 and Class II ESD capability. RoHS, REACH, lead-free, halogen-free, and conflict-minerals declarations require confirmation from the current manufacturer product documentation or declaration files.
