P82B96TD,112 - Dual I2C Bus Buffer 2-15V | NXP
MPN： P82B96TD,112 ✓ 啟用中P82B96TD,112 概覽
A bus buffer is an interface IC that sits between an I2C-bus master or slave and the physical bus wiring, isolating bus capacitance and translating logic levels. In the power management and interface hierarchy, the P82B96 belongs to the I2C buffer and repeater family, a subset of interface ICs used to extend the length, loading, and voltage tolerance of two-wire serial buses while preserving open-drain bus semantics.
Key features include interface capability between standard I2C-bus logic and buses operating at different voltage levels (for example the 350 uA SMBus, 3.3 V logic devices, and 15 V levels), low-impedance line driving for cable extension, and latch-up-free bipolar construction. ESD protection exceeds 3500 V HBM per JESD22-A114, 250 V MM (DIP package) and 400 V MM (SO package) per JESD22-A115, and 1000 V CDM per JESD22-C101.
Technically, each buffer channel provides two separate signal paths: a Tx path driving the buffered bus from the I2C side and an Rx path sensing the buffered bus and pulling the I2C pin low. Because Tx and Rx are separate directional signals, they may be connected directly without causing bus latching, or used with optocouplers for galvanic isolation or with balanced twisted-pair transmission lines.
Typical applications include extending I2C-bus reach across long cables, level-shifting between 3.3 V and 15 V bus domains, driving heavily loaded backplane buses, and isolating large-capacitance LED display clusters from a microcontroller I2C port.
Design consideration: keep pull-up resistor values appropriate to each bus domain; the buffer does not create its own pull-up current, so each bus segment must be terminated to its own logic level.
This page synthesizes distributor pricing, drop-in alternatives, comparison tables, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 P82B96TD,112 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： P82B96TD,112 （相同外形與佔位） — 差異在於 Package, Function, Channels, Input Capacitance.
PCA9600D,112
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
P82B96D
✅ 直接替換聯絡詢價
查看資料表 →TCA9517DGKR
✅ 直接替換聯絡詢價
查看資料表 →P82B96TD,112 規格
| 功能 | Dual bidirectional bus buffer |
| Number of Channels | 2 |
| Supply Voltage Range | 2 V to 15 V |
| Bus Interface Voltage Range | 2 V to 15 V |
| Maximum Bus Speed | 400 kHz |
| Bus Type | I2C / SMBus |
| Latch-up | Latch-up free (bipolar process) |
| ESD Protection HBM | > 3500 V (JESD22-A114) |
| ESD Protection MM | 400 V (SO package, JESD22-A115) |
| ESD Protection CDM | 1000 V (JESD22-C101) |
| Isolation Support | Optocoupler / twisted-pair capable via separate Tx/Rx paths |
| 封裝 | SOIC-8 (SO8) |
| 安裝類型 | Surface Mount |
| Packing / Suffix | ,112 = Tape & Reel, SMD, SO8 |
P82B96TD,112 腳位配置
| 腳位 1 | Tx — Channel x transmit output - drives buffered bus from I2C side |
| 腳位 2 | Rx — Channel x receive input - senses buffered bus, pulls Sx low when Rx low |
| 腳位 3 | Sx — Channel x I2C-bus side I/O (standard I2C logic levels) |
| 腳位 4 | GND — Ground |
| 腳位 5 | Sy — Channel y I2C-bus side I/O (standard I2C logic levels) |
| 腳位 6 | Ry — Channel y receive input - senses buffered bus, pulls Sy low when Ry low |
| 腳位 7 | Ty — Channel y transmit output - drives buffered bus from I2C side |
| 腳位 8 | VCC — Supply voltage, 2 V to 15 V |
典型應用
P82B96TD,112 適用於 6 應用s: I2C Bus Cable Extension, Voltage Level Translation (3.3 V to 15 V), LED Display Clusters via I2C, Galvanically Isolated I2C Links, SMBus Interfacing, Industrial Backplane / Heavy Bus Loading.
I2C Bus Cable Extension
The P82B96TD,112 is purpose-built for extending I2C buses beyond the ~1 m limit imposed by bus capacitance. Its low-impedance Tx output actively drives long cable wiring, so the master I2C pin sees only local capacitance, while the Rx path senses the far-end state at full drive strength. Because separate Tx and Rx signals are provided, twisted-pair cabling can be used for noise immunity on runs of tens of meters, with pull-up resistors sized per segment to maintain 400 kHz rise-time margins. Place a buffer at each cable end; the 2 V to 15 V supply tolerance lets each end run from its local logic rail.
推薦
Voltage Level Translation (3.3 V to 15 V)
Interfacing a 3.3 V microcontroller I2C port to a 15 V bus domain is a primary P82B96 use case. The Sx/Sy side operates at standard I2C logic levels while the Tx/Rx buffered side can be pulled up to any voltage within the 15 V rating, giving bidirectional level translation without latching risk. The bipolar input structure tolerates the higher bus levels that would damage ordinary 3.3 V transceivers. Designers should size pull-ups on the high-voltage side for the bus capacitance and verify low-level sink current meets the 3 mA I2C specification at the far end.
推薦
LED Display Clusters via I2C
Large LED display driver chains present heavy capacitive loading on the I2C bus. The NXP datasheet specifically cites driving LED displays as a target application: the P82B96's low-impedance buffered output supplies the extra sink and source capability needed to drive many driver IC inputs, while the master port remains unloaded. Each display segment can hang off its own buffer channel, isolating a fault-heavy display branch from the main control bus. The non-latching architecture is important here because heavily loaded buses are prone to stuck-low conditions with simple repeaters.
推薦
Galvanically Isolated I2C Links
Because the P82B96 provides separate directional Tx and Rx signals, it can drive an optocoupler pair to create a fully galvanically isolated I2C link. The Tx output drives the isolation-barrier LED while the Rx input receives the isolated return signal, and since the paths are unidirectional no bus latching occurs across the barrier. This suits medical equipment, industrial instrumentation, and ground-noise-separated subsystems where direct I2C connection is unsafe. The 2 V to 15 V supply range lets each isolation domain use its own local rail.
推薦
SMBus Interfacing
The P82B96TD,112 interfaces the 350 uA SMBus, which has stricter low-level current requirements than standard I2C, to standard I2C-bus masters and slaves. The buffer strengthens the SMBus segments' weak pull-up drive so a full I2C-capable bus can communicate with SMBus peripherals such as battery-management and power-supply ICs. The non-latching behavior prevents the data-hold contention common when SMBus devices share wires with stronger I2C devices. Verify SMBus timing (up to 100 kHz) is comfortably inside the P82B96's 400 kHz capability.
推薦
Industrial Backplane / Heavy Bus Loading
Industrial backplanes stack many I2C peripheral cards, quickly exceeding the 400 pF standard bus capacitance limit. Placing a P82B96TD,112 channel at the backplane root isolates card-loading from the controller, and additional buffers per card segment partition total capacitance below limits. The latch-up-free bipolar construction and ESD robustness exceeding 3500 V HBM per JESD22-A114 suit the harsh handling environment of card insertion. The wide 2 V to 15 V supply range supports both 3.3 V logic backplanes and legacy 5 V/12 V industrial rails without level-shifting circuitry.
推薦
推薦產品摘要
工程參考資料，適用於 P82B96TD,112 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | PCA9600D,112 | P82B96D | TCA9517D |
|---|---|---|---|---|
| Package | SOIC-8 (SO8) | SOIC-8 (SO8) - same | SOIC-8 (SO8) - same | SOIC-8 (SO8) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | Texas Instruments | Texas Instruments |
| Maximum Bus Speed | 400 kHz | 1 MHz | 400 kHz | 400 kHz |
| Architecture | Separate Tx/Rx directional paths, non-latching bipolar | Differential bus buffer family | Separate Tx/Rx directional paths, non-latching bipolar | A/B reference-based level translating buffer |
| Drop-in on Same Footprint | - | Verify pin map (related family) | Yes - pin-to-pin | No - different pinout |
主要差異化特點
- True 15 V bus tolerance with optocoupler/twisted-pair support (對比TCA9517D)
- Pin-to-pin TI second source (對比P82B96D)
- Trade-off: 400 kHz speed ceiling (對比PCA9600D,112)
設計說明
Place pull-up resistors on every bus segment the P82B96 creates - the buffer does not provide internal pull-ups. Size Sx/Sy side pull-ups to the local logic rail (typically 4.7k to 10k ohm for short traces) and Tx/Rx side pull-ups according to the buffered bus capacitance, targeting rise times that keep 400 kHz timing margins. Keep the buffer close to the connector or cable entry point so the master-side traces stay short and low-capacitance.
Do not short Tx directly to Rx expecting a simple repeater unless you understand the direction sensing: the datasheet states Tx and Rx may be connected directly without causing bus latching, which is valid, but wiring them incorrectly to the wrong bus segment will create contention. Also remember the Sx/Sy side is only compatible with normal I2C-bus logic levels - never connect Sx to a 15 V domain; the high-voltage capability belongs on the Tx/Rx side.
For long cable runs, use the separate Tx and Rx signals with twisted-pair wiring as described in the NXP P82B96 datasheet: one pair per direction avoids capacitive coupling between the driven and sensed lines and improves noise margins. For optocoupler isolation, choose optocouplers with propagation delays compatible with 400 kHz timing (total round-trip delay budget of roughly 1 us), and add series resistors per the optocoupler LED current requirements.
合規資訊
NXP lists P82B96TD as Active; ESD ratings per JESD22-A114/A115/C101 are given in the datasheet. Explicit RoHS/REACH/lead-free fields were not present in the retrieved data - confirm on nxp.com/part/P82B96TD.
