My Inquiry
My Account
NXP Semiconductors PCA9541BS/02,118
- Part No.:
- PCA9541BS/02,118
- Manufacturer:
- NXP Semiconductors
- Category:
- Specialized
- Package:
- 16-VQFN Exposed Pad
- Datasheet:
-
PCA9541BS/02,118.pdf
- Description:
- IC INTFACE SPECIALIZED 16HVQFN
- Quantity:
- Payment:
- Shipping:
Inventory:2,341
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
PCA9541BS/02,118 from NXP Semiconductors is a 2-to-1 bidirectional I²C-bus master selector IC with interrupt logic and reset, designed for high-reliability dual-master systems where continuous operation must be maintained during master failure or hot-swap maintenance. It supports 2.3 V to 5.5 V supply, 0–400 kHz clock frequency, 6.0 V tolerant I/O, and voltage-level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses. It enables bus recovery via nine-clock pulse initialization and isolates failed masters from downstream slave communication.
For engineers reviewing the PCA9541BS/02,118 datasheet, PCA9541BS/02,118 pinout, PCA9541BS/02,118 application, or PCA9541BS/02,118 equivalent, key selection considerations include channel selection timing (PCA9541/02 variant powers up with Channel 1 selected), HVQFN16 package thermal performance, interrupt masking capability for BUSLOST/BUSOK/BUSINIT events, and compatibility with SMBus standards in fault-tolerant industrial control and telecom infrastructure designs.
Technical Context
The PCA9541BS/02,118 implements a deterministic, non-arbitrated channel switching mechanism controlled via I²C writes to dedicated CONTROL registers per master, with state updates triggered only on STOP conditions. Its internal bus sensor detects non-idle downstream conditions and generates BUSOK interrupts when channel switching occurs mid-transaction.
It integrates dual independent interrupt enable registers (IE), a bus recovery oscillator, and pass-gate switches with VDD-referenced voltage limiting-enabling safe level-shifting without external translators. The RESET pin performs active-low hardware initialization, synchronizing with internal Power-On Reset to restore default register states and disconnect all upstream channels.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Function | 2-to-1 bidirectional I²C-bus master selector with interrupt logic, reset, and bus recovery |
| Supply Voltage | 2.3 V to 5.5 V - supports mixed-voltage system integration without level-shifters |
| Max Clock Frequency | 400 kHz - compatible with Fast-mode I²C and SMBus protocols |
| I/O Tolerance | 6.0 V - allows safe interfacing with higher-voltage peripherals regardless of VDD |
| Operating Temperature | −40 °C to +85 °C - qualified for industrial and telecom infrastructure environments |
| Package | HVQFN16 (4 × 4 × 0.85 mm, no leads) - thermally enhanced for high-density PCB layouts |
| ESD Protection | 2000 V HBM, 200 V MM, 1000 V CDM - meets robustness requirements for field-deployed equipment |
Pinout & Package
HVQFN16 package: plastic thermal-enhanced very thin quad flat package, 4 mm × 4 mm body, 0.85 mm height, 16 terminals, exposed thermal pad connected to VSS (pin 6) requiring soldering to PCB thermal pad with vias.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| INT0 (15) | Active LOW interrupt output 0 | Signals bus ownership change, BUSLOST, BUSOK, or BUSINIT completion to Master 0; requires external pull-up |
| SDA_MST0 (16) | Serial data line for Master 0 | Bidirectional I²C data path for upstream Master 0; 6.0 V tolerant, requires external pull-up |
| SCL_MST0 (1) | Serial clock line for Master 0 | Input-only clock path for Master 0; synchronized with SDA_MST0 for full-duplex I²C operation |
| RESET (2) | Active LOW reset input | Hardware-initiated initialization: clears internal state machine and forces default channel disconnect |
| SCL_MST1 (3) | Serial clock line for Master 1 | Input-only clock path for Master 1; electrically isolated from SCL_MST0 until channel selection |
| SDA_MST1 (4) | Serial data line for Master 1 | Bidirectional I²C data path for Master 1; shares no electrical connection with SDA_MST0 prior to switch |
| INT1 (5) | Active LOW interrupt output 1 | Signals bus events exclusively to Master 1; independently maskable via IE register |
| VSS (6) | Supply ground | Primary ground reference; die ground also tied to exposed thermal pad - must be soldered |
| A0–A3 (7–10) | Hardware address inputs | Set I²C slave address (7-bit); allow up to 16 devices on same bus; externally pulled to VSS or VDD |
| SCL_SLAVE (11) | Downstream serial clock | Drives slave-side I²C clock; passes SCL from selected master; includes bus recovery oscillator output |
| SDA_SLAVE (12) | Downstream serial data | Drives slave-side I²C data; bidirectional; incorporates bus sensor for non-idle detection |
| INT_IN (13) | Active LOW interrupt input | Propagates downstream interrupt signals to both INT0 and INT1 if enabled; maskable via IE register |
| VDD (14) | Supply voltage | Power source and voltage-reference for pass-gate threshold - defines max translated high-level voltage |
Key Features
| Feature | Design Value |
|---|---|
| Channel selection via I²C command | Enables software-controlled master handover without hardware reconfiguration or power cycle |
| Bus recovery/initialization function | Automatically sends 9 clock pulses + NACK + STOP to reset downstream slaves before channel switch |
| Bus traffic sensor | Detects non-idle downstream condition at switch time and triggers BUSOK interrupt for external recovery |
| Voltage-level translation | VDD-referenced pass gates allow 1.8 V/2.5 V/3.3 V masters to communicate with 5 V slaves safely |
| Independent interrupt masking | Per-master IE register enables selective suppression of BUSLOST, BUSOK, BUSINIT, and INT_IN events |
| Hot-insertion support | No glitch on power-up and active-low RESET ensure safe insertion/removal under live bus conditions |
Applications
| Telecom Line Card Redundancy | Industrial PLC Dual-Controller System |
|---|---|
|
Use Scenario: Primary and backup controllers manage shared I²C sensors and actuators on a telecom line card; one controller may be removed for firmware update or failure. IC Role / Device Role / Timing Role: Gatekeeper multiplexer that isolates failed or offline master while enabling seamless handover to operational master. Use Value: Eliminates bus lockup during maintenance, ensures uninterrupted monitoring of temperature, voltage, and fan status across redundant control paths. |
Use Scenario: Two programmable logic controllers share access to common I²C EEPROMs, ADCs, and DACs in an industrial automation cabinet. IC Role / Device Role / Timing Role: Fault-tolerant master selector enforcing exclusive downstream bus access with deterministic handover timing. Use Value: Prevents data corruption from concurrent master access and enables failover within <10 ms after BUSLOST detection. |
| Server Baseboard Management (BMC) | Medical Diagnostic Equipment |
|
Use Scenario: BMC and host CPU both require access to shared I²C temperature sensors, fan controllers, and FRU EEPROMs on server motherboard. IC Role / Device Role / Timing Role: Bus arbitration-free selector with hardware reset and interrupt-driven status reporting to both masters. Use Value: Enables BMC to monitor hardware health during OS boot or crash without interfering with host CPU I²C transactions. |
Use Scenario: Dual safety-certified microcontrollers supervise critical I²C-connected pressure, flow, and calibration sensors in diagnostic imaging systems. IC Role / Device Role / Timing Role: Certified-redundancy enabler ensuring one controller remains fully operational even if the other undergoes self-test or reset. Use Value: Meets IEC 62304 Class C requirements by guaranteeing continuous sensor readout and alarm generation during controller transitions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar I²C-bus master selector applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| PCA9544APW,118 | 4-channel I²C switch with interrupt logic; no built-in bus recovery or bus sensor; supports only 100 kHz standard-mode I²C | Lacks automatic 9-pulse initialization and non-idle detection - requires external firmware recovery routines | Select when expanding beyond 2 masters or when lower cost and simpler control suffice over fault tolerance |
| TCA9548APWR | 8-channel I²C switch with auto-addressing; no interrupt outputs, no RESET pin, no bus recovery, no voltage translation | Designed for multi-peripheral expansion, not dual-master redundancy; no master handover logic or fault isolation | Choose for low-cost peripheral multiplexing where master redundancy and bus integrity are not required |
Compared with PCA9544APW,118 and TCA9548APWR, the PCA9541BS/02,118 uniquely delivers deterministic dual-master handover with hardware-enforced bus recovery, real-time traffic sensing, and VDD-based level translation - making it irreplaceable in safety-critical, hot-swap-capable systems where bus continuity is non-negotiable.
Availability
PCA9541BS/02,118 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLC redundancy, and medical diagnostic equipment requiring stable component supply, long-term lifecycle assurance, and guaranteed traceable sourcing.
Supply support for PCA9541BS/02,118 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in interface, power management, and embedded processing technologies.
The PCA9541 product line was engineered specifically for high-availability I²C systems requiring dual-master redundancy, hot-swap resilience, and deterministic bus recovery - targeting telecom, industrial control, and medical equipment designers.
FAQ
What is the startup behavior of the PCA9541BS/02,118?
The PCA9541BS/02,118 is the /02 variant, which powers up with Channel 1 (Master 1) selected by default. This differs from /01 (Channel 0 at power-on) and /03 (no channel selected). The default state is enforced by internal POR logic and can be overridden immediately via I²C write to the CONTROL register without requiring RESET assertion.
How does the PCA9541BS/02,118 handle bus recovery during channel switching?
The PCA9541BS/02,118 performs hardware-initiated bus recovery only when BUSINIT = 1 is written to its CONTROL register before the master issues a STOP command. It then autonomously generates nine SCL_SLAVE clock pulses, releases SDA_SLAVE (equivalent to NACK), and asserts STOP - resetting downstream slaves to idle state prior to connecting the new master.
Can the PCA9541BS/02,118 translate between 1.8 V and 5 V I²C buses?
Yes. The PCA9541BS/02,118 uses VDD-referenced pass gates: when VDD = 1.8 V, it limits high-level voltage to ~1.8 V on all I/Os; when VDD = 5 V, it permits up to 5 V. This enables direct interconnection of 1.8 V masters with 5 V slaves - provided external pull-ups match respective bus voltages and I/Os remain within 6.0 V tolerance.
What is the function of the INT_IN pin on the PCA9541BS/02,118?
The INT_IN pin on the PCA9541BS/02,118 is an active LOW input that accepts interrupt signals from downstream I²C peripherals. When enabled via the IE register, it propagates those signals to both INT0 and INT1 outputs - allowing either master to respond to slave-generated alerts without polling, while preserving independent interrupt masking per channel.
Does the PCA9541BS/02,118 support hot insertion into a live I²C bus?
Yes. The PCA9541BS/02,118 features no-glitch power-up behavior and an active LOW RESET pin. When inserted into a live system, its internal state machine remains inactive until RESET is asserted or VDD stabilizes, preventing spurious SDA/SCL transitions. All I/Os are 6.0 V tolerant and include input filtering to suppress ESD-induced false triggers during insertion.
PCA9541BS/02,118 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- NXP Semiconductors
- Series:
- -
- Package/Case:
- 16-VQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Applications:
- 2-Channel I2C Multiplexer
- Interface:
- I2C
- Voltage - Supply:
- 2.3V ~ 3.6V, 4.5V ~ 5.5V
- Supplier Device Package:
- 16-HVQFN (4x4)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
PCA9541BS/02,118 FAQ
1.How can I place an order for PCA9541BS/02,118 through Aetrix?
Please submit a Request for Quotation (RFQ) for PCA9541BS/02,118 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for PCA9541BS/02,118 reliable?
The price and inventory of PCA9541BS/02,118 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PCA9541BS/02,118 is usually 5 days.
3.What payment methods are accepted for PCA9541BS/02,118?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PCA9541BS/02,118 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for PCA9541BS/02,118?
PCA9541BS/02,118 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your PCA9541BS/02,118 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for PCA9541BS/02,118?
For technical support, including PCA9541BS/02,118 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PCA9541BS/02,118 requirements.
6.How does Aetrix verify that PCA9541BS/02,118 is sourced from the original manufacturer or authorized distributors?
All PCA9541BS/02,118 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that PCA9541BS/02,118 meets industry standards.
7.What is the process for return or replacement of PCA9541BS/02,118?
All PCA9541BS/02,118 units undergo pre-shipment inspection (PSI). If there is an issue with PCA9541BS/02,118, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The PCA9541BS/02,118 part is unused and in its original packaging.
Return procedure for PCA9541BS/02,118:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
PCA9541BS/02,118 Tags
-
NVT4857UKAZ
NXP Semiconductors
-
TCA8418RTWR
Texas Instruments
-
PCA9546APWR
Texas Instruments
-
MD0100N8-G
Microchip Technology
-
PCA9548APW,118
NXP Semiconductors
-
PCA9540BDP,118
NXP Semiconductors
-
PCA9548APWR
Texas Instruments
-
PCA9546APW,118
NXP Semiconductors
-
PTN3360DBS,518
NXP Semiconductors
-
PCA9546ABS,118
NXP Semiconductors
-
PCA9518PWR
Texas Instruments
-
PCA9545APW,118
NXP Semiconductors
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
