P82B96TD - Dual I2C Bus Buffer 2-15V 400kHz | NXP
MPN: P82B96TD ✓ Active| Qty | Unit Price | Extended |
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| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
P82B96TD Overview
An I2C bus buffer, also called a bus repeater or redriver, is an interface IC that sits between an I2C master and one or more slaves to isolate bus capacitance, translate logic levels, and extend cable length. Within the signal-integrity hierarchy (bus buffer -> line driver -> interface IC -> signal conditioning IC), buffers like the P82B96TD allow a small I2C segment to drive long or heavily loaded lines without violating the 400 pF bus capacitance limit of the standard I2C specification.
Key features include two independent buffer channels handling both SCL and SDA, a wide supply range of 2 V to 15 V, support for 15 V bus levels and low-impedance lines, and low operating supply current of approximately 900 uA. The bipolar process is latch-up free and provides ESD protection exceeding 3500 V HBM per JESD22-A114, 250 V MM (DIP package) per JESD22-A115, and 1000 V CDM per JESD22-C101.
The buffer splits each I2C signal into forward and reverse paths (Tx/Rx and Ty/Ry), using slightly different logic-low voltage levels at the Sx/Sy side to prevent latch-up without a direction-control pin. This architecture allows interfacing between standard 3.3 V or 5 V I2C logic, the 350 uA SMBus, and 15 V level systems on the same PCB.
Typical applications include I2C bus extension over long cables, level shifting between 3.3 V microcontrollers and 5 V or 15 V peripherals, capacitive bus isolation for large multi-drop networks, and SMBus-to-I2C interfacing in industrial and telecom systems.
Design consideration: two or more Sx or Sy pins must never be connected to the same node, as the architecture does not support this; when cascading buffers, connect Tx/Rx signals of one stage to Sx/Sy of the next. Pull-up resistor sizing must account for the offset logic-low levels at Sx/Sy.
This page synthesizes distributor availability data, verified drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for P82B96TD — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with P82B96TD (same form factor and footprint) — differing in Function, Number of Channels, Package, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PCA9600D,118
✅ Drop-In✓ In Stock
$1.02 / Unit
View Datasheet →P82B96D
✅ Drop-In📋 Reference alternative (not in catalog)
P82B96TD Specifications
| Function | Dual bidirectional I2C bus buffer |
| Number of Channels | 2 |
| Supply Voltage Range | 2 V to 15 V |
| Bus Voltage Levels Supported | Up to 15 V |
| Maximum Data Rate | 400 kHz |
| Operating Supply Current | 900 uA (typical) |
| Protocol Compatibility | I2C-bus, SMBus (350 uA) |
| Logic Level Translation | 3.3 V / 5 V I2C logic to 15 V bus levels |
| Latch-Up Immunity | Latch-up free (bipolar process) |
| ESD Protection HBM | > 3500 V (JESD22-A114) |
| ESD Protection CDM | 1000 V (JESD22-C101) |
| Operating Temperature Range | -40 C to +85 C |
| Package | SO8 (SOIC-8, SOT96-1) |
| Mounting Type | Surface Mount |
| Introduction Date | March 06, 2001 |
| ECCN | EAR99 |
| RoHS Status | unknown |
P82B96TD Pin Configuration
| Pin 1 | Tx — SDA buffer drive-side I/O (external bus segment) |
| Pin 2 | Rx — SDA buffer receive-side I/O (external bus segment) |
| Pin 3 | Sx — SDA logic-side I/O (standard I2C-bus logic levels) |
| Pin 4 | VCC — Supply voltage, 2 V to 15 V |
| Pin 5 | Sy — SCL logic-side I/O (standard I2C-bus logic levels) |
| Pin 6 | Ry — SCL buffer receive-side I/O (external bus segment) |
| Pin 7 | Ty — SCL buffer drive-side I/O (external bus segment) |
| Pin 8 | GND — Ground |
Typical Applications
P82B96TD is suitable for 6 applications: I2C Bus Extension over Long Cables, 3.3 V to 15 V I2C Level Shifting, Capacitive Bus Isolation in Multi-Drop Networks, SMBus to I2C Interfacing, Industrial Automation Control Buses, Telecom and Rack-Level Board Interconnect.
I2C Bus Extension over Long Cables
Standard I2C is limited by bus capacitance (typically 400 pF), which restricts cable length to a few meters. The P82B96TD solves this by regenerating the SCL and SDA signals: the microcontroller-side Sx/Sy pins see only local low-capacitance loads, while the Tx/Rx and Ty/Ry sides drive long or low-impedance cables at up to 15 V levels with stronger drive current. Per the NXP datasheet, two P82B96 buffers can be cascaded (Tx/Rx of one feeding Sx/Sy of the next) to span even longer distances. The 400 kHz Fast-mode rate is maintained, and the latch-up-free bipolar process plus >3500 V HBM ESD rating provide the robustness needed for industrial cable runs. Star or daisy-chain topologies must be planned so no two Sx or Sy pins share a node.
Recommended
3.3 V to 15 V I2C Level Shifting
Many industrial actuators, LED drivers, and battery-management peripherals use bus voltages well above 5 V. The P82B96TD, with its 2 V to 15 V supply range, natively bridges a 3.3 V microcontroller I2C port to 15 V-level buses without discrete transistor level shifters. The Sx/Sy side follows normal I2C logic thresholds for the 3.3 V domain, while the Tx/Rx side swings toward the 15 V rail with low-impedance drive, improving noise immunity on the high-voltage segment. According to the NXP datasheet, this configuration also supports the 350 uA current levels of SMBus. Pull-up resistors on the Tx/Rx side must be recalculated for the higher rail to respect sink-current limits of slave devices.
Recommended
Capacitive Bus Isolation in Multi-Drop Networks
Large multi-drop I2C networks - rack systems, backplanes, sensor clusters - accumulate trace and input capacitance that degrades signal edges and can exceed the 400 pF I2C limit. Inserting a P82B96TD channel between the controller segment and each loaded segment partitions the capacitance: the master only drives its local Sx/Sy node, and each Tx/Rx segment is regenerated with the buffer's stronger drive. Because the Sx/Sy-side offset logic-low levels prevent latch-up without a direction pin, the solution is fully bidirectional at 400 kHz with no software changes. The TI P82B96 datasheet warns that two Sx or Sy pins must never share a node, so each buffered branch must have its own dedicated channel.
Recommended
SMBus to I2C Interfacing
SMBus devices (power managers, battery packs, thermal monitors) use a 350 uA low-current variant of I2C with tighter timing and voltage constraints. The P82B96TD explicitly supports interfacing between standard I2C and the 350 uA SMBus: the Sx/Sy side presents standard I2C logic levels compatible with both protocol families, while the buffer absorbs the sink-current differences between segments. This isolates a 3.3 V or 5 V microcontroller I2C port from SMBus current requirements and allows mixed networks. Per the NXP datasheet the buffer is non-latching, so bidirectional SMBus transactions (including ARP and PEC reads at up to 100 kHz, and 400 kHz where devices allow) pass without direction-control logic or firmware overhead.
Recommended
Industrial Automation Control Buses
Factory floors combine electrically noisy environments with long wiring runs - exactly where I2C fails without buffering. The P82B96TD's bipolar, latch-up-free process, -40 C to +85 C operating range, and ESD ratings exceeding 3500 V HBM (JESD22-A114) and 1000 V CDM (JESD22-C101) make it a durable front line for PLC I/O expansion, motor-drive configuration ports, and distributed sensor modules. Running the remote segment at up to 15 V gives substantially higher noise margins than 3.3 V I2C. Designers should route buffered segments away from switching-node wiring and use twisted-pair cable for SCL/SDA plus ground to control coupling, keeping the 400 kHz Fast-mode timing margin intact across the full temperature range.
Recommended
Telecom and Rack-Level Board Interconnect
Telecom shelves use I2C for FRU (field-replaceable-unit) identity EEPROMs, hot-swap controllers, and fan managers, frequently spanning backplane wiring that exceeds native I2C capacitance limits. The P82B96TD regenerates the bus at each shelf segment while supporting SMBus 350 uA current levels common in telecom power management. Its 2 V to 15 V supply tolerance accommodates mixed 3.3 V/5 V shelf logic domains, and the EAR99 ECCN simplifies global logistics. Per the NXP datasheet application circuits, buffer stages can be chained via Tx/Rx-to-Sx/Sy connections for multi-shelf trees, provided each Sx/Sy node remains exclusive to one buffer. The SO8 footprint keeps the BOM footprint small on dense line cards.
Recommended
Recommended Products Summary
Engineering reference data for P82B96TD — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PCA9600D | P82B96D |
|---|---|---|---|
| Package | SO8 (SOIC-8) | SO8 (SOIC-8) - same footprint | SOIC-8 - same footprint |
| Brand | NXP Semiconductors | NXP Semiconductors | Texas Instruments |
| Supply Voltage Range | 2 V to 15 V | 2.7 V to 5.5 V (5 V tolerant I/O) | 2 V to 15 V |
| Maximum Data Rate | 400 kHz | 1 MHz (Fast-mode Plus capable) | 400 kHz |
| Number of Channels | 2 | 2 | 2 |
| Bus Levels Supported | Up to 15 V | Up to 15 V (enhanced drive) | Up to 15 V |
Key Differentiators
- Widest supply range in its drop-in class (vs PCA9600D)
- Identical second-source from TI (vs P82B96D)
- Non-latching bipolar architecture (vs PCA9600D)
Design Notes
Never connect two or more Sx or Sy pins to the same electrical node. The P82B96 avoids latch-up by offsetting the logic-low voltage at Sx/Sy; tying two logic-side pins together creates a competing logic-low condition that corrupts data or causes bus lockup. For tree topologies, cascade stages by connecting the Tx/Rx (or Ty/Ry) outputs of one buffer to the Sx (or Sy) input of the next, as shown in the NXP P82B96 datasheet application circuits. Verify this rule in every multi-buffer schematic review - it is the single most common design error with this family.
Pull-up resistors must be sized independently for each side of the buffer. The Sx/Sy side obeys standard I2C logic thresholds and typically uses 2.2k to 10k pull-ups to the logic rail (3.3 V or 5 V). The Tx/Rx side can be pulled to up to 15 V; total sink current at the Tx pin must stay within the datasheet low-level output current rating when the rail is high. Estimated: with a 15 V pull-up, a 4.7k resistor sinks roughly 3.2 mA at a 0 V low level - confirm this current against the P82B96 datasheet absolute maximum and low-level input current limits before finalizing.
Place a 100 nF ceramic decoupling capacitor directly across VCC (pin 4) and GND (pin 8) within 5 mm of the package. For cable-driving applications, route the Tx/Rx and Ty/Ry traces away from fast digital or switching-node signals and consider series damping resistors (22 to 47 ohm) at cable exit points to control ringing on long lines. Ground the cable shield at the buffer board only to avoid ground loops between shelves. These practices preserve the 400 kHz edge rates the buffer is specified to regenerate.
Compliance Information
Halogen-free status was referenced in third-party data but not confirmed; verify RoHS/REACH status on the official NXP product page for P82B96TD before procurement. ECCN EAR99 per Globalspec data.
