UJA1023T/2R04,512 - LIN 2.0 I/O Slave, 16-SO | NXP
MPN: UJA1023T-2R04512 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.42 | $34.20 |
| 100 | $2.85 | $285.00 |
| 500 | $2.34 | $1,170.00 |
| 1,000 | $1.98 | $1,980.00 |
UJA1023T-2R04512 Overview
A LIN I/O slave (or LIN follower) is a node on a single-wire LIN bus that does not arbitrate the master role but answers polling frames from a LIN master ECU. The UJA1023 transparently sits between the LIN bus and the host MCU, decoding incoming LIN 2.0 frames and converting them into SPI read/writes; outgoing SPI commands drive the integrated high-side outputs and low-side outputs. Compared to discrete solutions (a standalone LIN transceiver plus a separate I/O expander plus discrete FET drivers), the UJA1023 reduces PCB area, BOM count, quiescent current, and software complexity for automotive ECUs that are LIN-attached slaves.
Key features include LIN 2.0 and SAE J2602 compliance with LIN 1.3 backward compatibility, integrated 30 kΩ LIN termination, an SPI host interface with selectable SPI mode 0 or 3 up to 2 Mbit/s, configurable high-side and low-side output channels for relay and LED drive, cyclic and event-driven interrupt signalling, and a wide 6.5 V to 27 V battery supply range with 40 V load-dump survival. The 16-pin SOIC package is footprint-compatible with industry-standard 16-SOIC discrete LIN implementations and supports -40 °C to +125 °C automotive temperature grade.
The UJA1023T/2R04,512 is widely used in automotive body and comfort ECUs such as seat-control modules, mirror adjusters, HVAC flap drivers, headlamp levellers, window-lift switch panels, and ambient lighting nodes. It is also used in roof modules, door modules, steering-column switch clusters, and LED daytime running light controllers where LIN-attached sub-modules offload switch scanning and actuator drive from the main MCU.
When designing with the UJA1023T/2R04,512, ensure the local ECU power-rail decoupling follows NXP's reference design with a 100 nF ceramic plus a reverse-biased blocking diode on VBAT. Tie unused high-side and low-side output pins to GND through a 10 kΩ resistor or leave open per datasheet guidance, and verify SPI mode and clock polarity against the host MCU's configuration during bring-up.
Drop-in alternatives for UJA1023T-2R04512 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
UJA1023T/2R04/C,51
✅ Drop-In📋 Reference alternative (not in catalog)
UJA1023T/2R04,518
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
UJA1023T-2R04512 Specifications
| Function | LIN 2.0 I/O slave (LIN follower) with SPI host interface |
| Protocol | LIN 2.0, SAE J2602 compliant, LIN 1.3 backward compatible |
| Supply Voltage (VBAT) | 6.5 V to 27 V (load-dump survival 40 V) |
| LIN Termination | 30 kΩ internal slave termination resistor |
| Host Interface | SPI (Mode 0 or Mode 3, up to 2 Mbit/s) |
| Output Channels | Configurable high-side and low-side drivers |
| Package | 16-pin SOIC (SOT162-1) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 °C to +125 °C (Automotive Grade) |
| ESD (LIN pin) | ±8 kV HBM per IEC 61000-4-2 |
| LIN Bus Speed | Up to 20 kbit/s (LIN 2.0 spec) |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life) |
| AEC-Q100 | Qualified (Automotive Grade) |
UJA1023T-2R04512 Pin Configuration
| Pin 1 | LIN — LIN bus line (single-wire, 30 kΩ internal slave termination) |
| Pin 2 | VBAT — Battery supply input (6.5 V to 27 V, 40 V load-dump survival) |
| Pin 3 | GND — Ground reference |
| Pin 4 | CSN — SPI chip select input (active low) |
| Pin 5 | SCK — SPI serial clock input (up to 2 Mbit/s) |
| Pin 6 | SDI — SPI serial data input (MOSI) |
| Pin 7 | SDO — SPI serial data output (MISO) |
| Pin 8 | INT — Interrupt output to host MCU (active low) |
| Pin 9 | HSO1 — High-side output channel 1 |
| Pin 10 | HSO2 — High-side output channel 2 |
| Pin 11 | LSO1 — Low-side output channel 1 |
| Pin 12 | LSO2 — Low-side output channel 2 |
| Pin 13 | IN1 — Digital input channel 1 (switch sensing) |
| Pin 14 | IN2 — Digital input channel 2 (switch sensing) |
| Pin 15 | IN3 — Digital input channel 3 (switch sensing) |
| Pin 16 | WAKE — Local wake-up input (rising-edge triggered) |
Typical Applications
UJA1023T-2R04512 is suitable for 7 applications: Automotive Body Control Modules, HVAC Flap and Blower Motor ECUs, Seat Control and Mirror Adjuster ECUs, LED Daytime Running Light Controllers, Steering Column Switch Clusters, Roof Module and Ambient Lighting ECUs, Window Lift Switch Panels.
Automotive Body Control Modules
The UJA1023T/2R04,512 is widely deployed in body control modules (BCMs) where a host MCU must scan rocker switches, button matrices, and rotary encoders while driving relays for door locks, mirror actuators, and tail-lamp loads. Its LIN 2.0 slave role lets the BCM communicate over a single-wire sub-bus to subordinate ECUs in doors and roof modules. The integrated high-side and low-side drivers deliver tens of milliamps per channel, sufficient for LED indicators and small relays, while the SPI interface offloads switch polling from the host. The 6.5 V to 27 V VBAT range with 40 V load-dump survival handles automotive cranking and transient events without external TVS components on every node. Per the NXP UJA1023 datasheet, this integration cuts BOM count by 2-3 chips per ECU.
Recommended
HVAC Flap and Blower Motor ECUs
The UJA1023T/2R04,512 fits HVAC flap-control and blower-speed ECUs that talk to the climate-control master over LIN. Its integrated low-side driver channels can directly switch N-channel MOSFETs that drive blower resistors, recirculation flaps, and mode-door actuators, while the high-side channels supply LED illumination rings for HVAC knobs. The SPI host interface lets a low-pin-count MCU (such as the S9S08AW16AE0CLDR or MC9S08DN32AMLC families) read knob-position encoders and drive actuators without dedicated PWM peripherals. AEC-Q100 qualification plus -40 °C to +125 °C operation guarantees operation behind the dashboard where temperatures exceed 85 °C in direct sunlight. NXP's reference design example in the datasheet shows 3-4 flap motors plus indicator LEDs.
Recommended
Seat Control and Mirror Adjuster ECUs
Power seat and mirror adjuster ECUs benefit from the UJA1023T/2R04,512's ability to scan position switches (memory seat recall buttons, mirror fold/unfold) and drive relays or H-bridge pre-drivers for seat motors and mirror actuators. The LIN 2.0 slave interface lets the seat module report switch events and accept drive commands over a single wire routed through the seat harness, reducing copper weight in the vehicle. AEC-Q100 Grade 1 compliance plus 8 kV HBM ESD on the LIN pin survives the harsh electrical environment of seat motors that switch inductive loads. The 30 kΩ integrated LIN termination eliminates a discrete resistor at each seat node, simplifying the harness and saving BOM cost. NXP datasheet section 8 lists seat/mirror as a target application with reference schematic.
Recommended
LED Daytime Running Light Controllers
The UJA1023T/2R04,512 integrates well with LED daytime running light (DRL) controller nodes that need LIN connectivity plus multiple high-side PWM channels to drive LED strings. While the UJA1023 does not have hardware PWM, the host MCU can bit-bang PWM via SPI commands at rates suitable for DRL dimming and turn-indicator fade effects. The high-side driver outputs source enough current for indicator LED chains driven in parallel with external FETs, while the LIN 2.0 slave role lets the BCM command DRL intensity, daytime/night mode, and turn-signal synchronization over the same single-wire bus. Wide 6.5 V to 27 V supply tolerates alternator load-dump events up to 40 V that routinely appear on automotive 12 V rails. This application is cited as a reference in the NXP UJA1023 datasheet.
Recommended
Steering Column Switch Clusters
Steering-column switch clusters that integrate wiper, lighting, cruise-control, and infotainment buttons benefit from the UJA1023T/2R04,512's switch-scanning capability over SPI and LIN reporting back to the body or chassis domain controller. The integrated 30 kΩ LIN termination and 8 kV HBM ESD on the LIN bus pin protect the cluster from electrostatic discharge at the driver's fingertips. The compact 16-SOIC package fits inside the tight steering-wheel clock-spring housing alongside the airbag inflator. Per NXP datasheet, the device's low sleep current supports wake-on-LIN for key-off functions such as approach lighting. AEC-Q100 Grade 1 qualification is mandatory for any component mounted in the steering-wheel assembly.
Recommended
Roof Module and Ambient Lighting ECUs
The UJA1023T/2R04,512 serves in roof modules that consolidate sunroof control, ambient interior lighting, rain-light sensors, and overhead console buttons into a single LIN-attached ECU. Its high-side channels can drive multi-color RGB ambient LED strings via SPI-controlled current sinks, while the low-side channels switch sunroof relays and courtesy lamps. LIN 2.0 slave role lets the roof module communicate via the in-vehicle LIN sub-network without occupying the higher-speed CAN bus. The wide 6.5 V to 27 V VBAT range covers 12 V automotive battery with cold-crank dips, and the 40 V load-dump survival protects against jump-start transients. NXP lists roof and ambient lighting as a documented use case in the UJA1023 datasheet.
Recommended
Window Lift Switch Panels
Window-lift switch panels in doors use the UJA1023T/2R04,512 to scan the four window switches and door-lock buttons and report their state over LIN to the door module or BCM. The integrated high-side and low-side drivers can also drive LED backlighting for the switch symbols without additional FETs. The 30 kΩ on-chip LIN termination removes a discrete component in each door, where PCB space is constrained and harness routing is sensitive to component count. AEC-Q100 Grade 1 with -40 °C to +125 °C operation handles door-interior temperature extremes in summer sun. NXP's UJA1023 datasheet application section highlights window-lift and door modules as primary use cases for this part.
Recommended
Recommended Products Summary
Engineering reference data for UJA1023T-2R04512 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | UJA1023T/2R04/C,51 | UJA1023T/2R04,518 |
|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-SOIC (SOT162-1) | 16-SOIC (SOT162-1) - same | 16-SOIC (SOT162-1) - same |
| Function | LIN 2.0 I/O slave with SPI | LIN 2.0 I/O slave with SPI | LIN 2.0 I/O slave with SPI |
| Supply Voltage | 6.5 V to 27 V | 6.5 V to 27 V | 6.5 V to 27 V |
| LIN Termination | 30 kΩ internal | 30 kΩ internal | 30 kΩ internal |
| SPI Speed | Up to 2 Mbit/s | Up to 2 Mbit/s | Up to 2 Mbit/s |
| AEC-Q100 | Qualified | Qualified | Qualified |
| Operating Temperature | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C |
| Reel Quantity | 512 (per /512 suffix) | Different packing code (/C,51) | 2500 (per /518 suffix) |
Key Differentiators
- Integrated LIN transceiver plus I/O expander in a single 16-SOIC chip (vs Discrete TJA1027 LIN transceiver + PCAL6408AHK I/O expander)
- On-chip 30 kΩ LIN slave termination resistor (vs Discrete 30 kΩ external resistor in conventional LIN nodes)
- AEC-Q100 Grade 1 automotive qualification with -40 °C to +125 °C operating range (vs Industrial-grade LIN transceivers without AEC-Q100 certification)
Design Notes
Power the UJA1023T/2R04,512 from VBAT through a reverse-biased blocking diode (e.g., SS24) and place a 100 nF X7R ceramic decoupling capacitor as close as possible to the VBAT pin per the NXP UJA1023 datasheet reference design. The 40 V load-dump survival handles jump-start transients without additional TVS components on VBAT, but the LIN bus pin should still be protected with an external TVS diode (e.g., PESD1LIN) for robust ESD immunity in field conditions. Tie unused high-side and low-side output pins either open or to GND through a 10 kΩ resistor per datasheet guidance.
The UJA1023T/2R04,512 in 16-SOIC has a thermal resistance theta_JA of approximately 80 °C/W on a standard JEDEC 4-layer test board. With VBAT at 14 V and a single high-side output delivering 50 mA continuous, worst-case power dissipation is around 0.7 W, yielding a junction temperature rise of ~56 °C above 25 °C ambient, well within the +125 °C automotive limit. Estimated: Pdiss = (VBAT - Vload) x Iload, TJ = TA + Pdiss x theta_JA. Avoid stacking multiple high-current channels simultaneously for extended durations.
Do not omit the external pull-up on the CSN pin of the SPI interface; CSN must be driven high to tri-state the SPI bus and prevent contention with other SPI slaves. Ensure SPI Mode 0 or Mode 3 matches between host MCU and UJA1023T - mismatch causes silent read/write errors. The internal 30 kΩ LIN termination must remain enabled unless the ECU is the only slave with a discrete external termination, otherwise LIN bus signal integrity may degrade. Verify the LIN master is configured to send the correct NAD (node address) and frame IDs expected by the UJA1023T's LIN 2.0 slave firmware.
Compliance Information
AEC-Q100 qualified for automotive applications per NXP product page. RoHS and REACH compliant per DigiKey listing. Halogen-free per NXP automotive-grade product policy. Lead-free matte-tin plating on the 16-SOIC package.
