ADC08134CIWMX - 8-Bit 4-Ch SAR ADC, Serial I/O | Texas Instruments
MPN: ADC08134CIWMX ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.92 | $3.92 |
| 10 | $3.52 | $35.20 |
| 100 | $3.13 | $313.00 |
| 500 | $2.81 | $1,405.00 |
| 1,000 | $2.49 | $2,490.00 |
ADC08134CIWMX Overview
Key features include 8-bit resolution, 4 analog input channels, a SAR conversion architecture optimized for low-power operation, and an on-chip reference. The serial interface reduces pin count and eases isolated or remote-sensor designs where galvanic isolation of the data path is required. The wide SOIC-14 package provides industry-standard land pattern compatibility with the rest of the ADC0813x family, which simplifies PCB layout reuse across single, dual, and multi-channel variants.
The device belongs to the successive-approximation ADC category, a subtype of data-converter ICs used wherever low-latency, deterministic sampling of one or more analog inputs is required. SAR ADCs sit between sigma-delta ADCs (which offer higher resolution at lower speeds) and flash ADCs (highest speed, lowest resolution). ADC SARs deliver one conversion per acquisition cycle, making them well suited to multiplexed sensor monitoring where a microcontroller reads many channels in sequence.
The part was originally introduced by National Semiconductor and is now served by Texas Instruments following acquisition of that business, with the datasheet titled "ADC08131/ADC08134/ADC08138 8-Bit High-Speed Serial I/O A/D Converters with Multiplexer Options, Voltage Reference, and Track/Hold Function." Industrial temperature grade and gull-wing SOIC terminal form make it suitable for through-hole-style reflow on standard SMT lines.
Typical applications include industrial process-control analog front ends, multi-sensor data acquisition boards, battery monitoring multiplexed inputs, and remote transducer digitizer modules. The combination of on-chip reference and track/hold makes the ADC08134CIWMX attractive for cost-sensitive designs where a separate reference IC and sample-and-hold would otherwise add bill-of-materials cost.
Design consideration: when migrating to or from this part, note that the family pinout differs by channel count - verify MUX outputs and serial timing against the target datasheet before reuse. The track/hold acquisition time and serial clock frequency together bound the per-channel throughput and must be sized so the multiplexer settling plus conversion plus acquisition fits the system sample budget. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ADC08134CIWMX — 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 ADC08134CIWMX (same form factor and footprint) — differing in Resolution, RoHS Status, Data Interface, Package / Case, Input Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC08134CIWM
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08131CIWMX
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08138CIWMX
✅ Drop-In✓ In Stock
$3.35 / Unit
View Datasheet →ADC08832IWM/NOPB
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.92 / Unit
View Datasheet →AD7994BRU-0REEL
✅ Drop-In✓ In Stock
$4.68 / Unit
View Datasheet →AD7993BRU-0REEL
✅ Drop-In✓ In Stock
$3.4 / Unit
View Datasheet →ADC08134CIWMX Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Number of Input Channels | 4 |
| Conversion Architecture | SAR (Successive Approximation) |
| Data Interface | NSC MICROWIRE / Serial |
| Input Type | Single-ended, multiplexed |
| On-Chip Voltage Reference | Yes |
| Track/Hold Amplifier | On-chip |
| Operating Temperature Range | Industrial grade (-40C to +85C typical, per part marking) |
| Package / Case | 14-SOIC (0.295-inch / 7.50 mm width) |
| Terminal Form | Gull Wing |
| Pin Count | 14 |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| RoHS Status | Compliant (per TI product page) |
| AEC-Q100 Qualification | Not qualified |
ADC08134CIWMX Pin Configuration
| Pin 1 | V+ — Positive supply voltage |
| Pin 2 | GND — Ground |
| Pin 3 | VIN0 — Analog input channel 0 (MUX input) |
| Pin 4 | VIN1 — Analog input channel 1 (MUX input) |
| Pin 5 | VIN2 — Analog input channel 2 (MUX input) |
| Pin 6 | VIN3 — Analog input channel 3 (MUX input) |
| Pin 7 | VREF — Voltage reference input / output pin |
| Pin 8 | REFGND — Reference ground (low-noise return) |
| Pin 9 | CS — Chip select input (active low, for serial interface) |
| Pin 10 | DOUT — Serial data output (MICROWIRE-compatible) |
| Pin 11 | SCLK — Serial clock input |
| Pin 12 | MUX_ADDR — Multiplexer channel address selection |
| Pin 13 | NC — Not connected (per datasheet) |
| Pin 14 | NC — Not connected (per datasheet) |
Typical Applications
ADC08134CIWMX is suitable for 6 applications: Industrial Process-Control Analog Front End, Multi-Sensor Data Acquisition Board, Battery Pack Cell-Voltage Monitor, Remote Transducer Digitizer Module, HMI Panel Multi-Knob Input Reader, Legacy Replacement / Industrial Repair Channel.
Industrial Process-Control Analog Front End
The ADC08134CIWMX fits industrial process-control analog front ends because its 4-input multiplexer plus 8-bit SAR core plus on-chip voltage reference lets a single IC digitize four transducer channels (such as temperature, pressure, flow, level) without external analog switches or reference parts. The on-chip track/hold amplifier provides simultaneous-acquisition behavior that prevents MUX channel-to-channel crosstalk during multiplexed scanning. The wide-body 14-SOIC lands on the same reflow profile as legacy industrial PLC analog input cards, and the NSC MICROWIRE-compatible serial interface reduces opto-isolator channel count in 4-20 mA loop-powered isolator designs. Maximum throughput is set by the serial clock and conversion time, typically adequate for process loops with 100 ms to 1 s update periods. Designers use it where 1% accuracy from the 8-bit converter is sufficient, e.g. conditioning telemetry signals for offloading to a microcontroller's SPI port.
Recommended
Multi-Sensor Data Acquisition Board
Battery-monitoring and sensor-aggregation boards benefit from the ADC08134CIWMX because the 4-channel MUX lets one converter scan four cell voltages, thermistor taps, or transducer outputs sequentially, keeping the bill of materials to one data converter plus a microcontroller. The SAR architecture delivers a single conversion in a deterministic number of clock cycles, simplifying the software timing budget in firmware compared to sigma-delta converters that require digital filtering. The wide SOIC-14 body and 0.295-inch width match the standard land pattern reused across countless legacy data-acquisition daughterboards. Combined with the on-chip voltage reference, the ADC08134CIWMX holds total unadjusted error consistent with industrial-grade data logging. The serial MICROWIRE interface parks cleanly on a single SPI peripheral of any 8/16/32-bit MCU and uses only 3 to 4 microcontroller pins, freeing GPIOs for relays or UART links.
Recommended
Battery Pack Cell-Voltage Monitor
Inside a battery-management module, the ADC08134CIWMX digitizes up to four series-stacked cell voltages through resistive dividers per channel, with the on-chip reference and track/hold keeping the SAR conversion stable across the 8-bit quantisation. The 4-channel input MUX is the natural fit for 4-cell Li-ion or 4-cell lead-acid stacks, and the SOIC-14 wide-body survives the thermal stress of reflow on automotive-style BMS PCBs (not AEC-Q100 qualified, so use only in non-automotive battery packs). The serial interface consumes only one SPI bus of the host battery-management MCU, leaving the I2C bus free for SMBus / smart-battery comms to a system charger. Throughput is bounded by serial clock and conversion cycles, but for cell-balancing-decision sampling at sub-1 kHz, it is sufficient. The NRND status pushes designers of new battery packs to also evaluate the AD7994BRU-0REEL I2C 12-bit upgrade or the ADC084S021 SAR series for higher resolution.
Recommended
Remote Transducer Digitizer Module
For remote transducer digitizer modules where the analog signal must cross an isolation barrier to a host controller, the ADC08134CIWMX's MICROWIRE serial interface minimises the number of digital lines crossing the isolator, reducing BOM cost of optocouplers or digital isolators. The 4-channel MUX lets one module scan up to four sensor types (RTD, thermocouple, strain gauge, pressure) at a remote station. The on-chip voltage reference eliminates the need to span an extra analog reference wire across the isolation barrier. Industrial operating temperature range suits outdo or factory-floor enclosures. Throughput is set by serial SCLK and SAR conversion time, typically tens of microseconds per conversion, well matched to the latency budget of supervisory telemetry loops.
Recommended
HMI Panel Multi-Knob Input Reader
In a human-machine interface (HMI) panel, the ADC08134CIWMX reads up to four potentiometer or rotary-encoder-derived analog voltages through the MUX with 8-bit resolution, sufficient for joystick position, brightness level, mode selector, or trimmer feedback. The SOIC-14 Wide package fits alongside other surface-mount components on a compact HMI daughterboard. The on-chip reference simplifies the analog supply chain to one stable LDO feeding the ADC; no separate ref IC is required. The serial MICROWIRE interface reduces microcontroller pin count, freeing more GPIOs for buttons, LEDs, and display lines of the HMI. For higher-resolution HMI knobs (e.g. 10-bit or 12-bit fade control), designers escalate to the pin-compatible 10-bit AD7993BRU-0REEL or 12-bit AD7994BRU-0REEL while keeping the same SOIC-14 PCB footprint.
Recommended
Legacy Replacement / Industrial Repair Channel
Because the ADC08134CIWMX is now NRND on the TI product tree, it is most commonly sourced today for repair of industrial PLC analog-input cards, programmable logic controllers, and other legacy field devices that originally used this part in their 1990s/2000s designs. The wide 14-SOIC body and 'CI' industrial temperature grade align with IPC-A-610 Class 2/3 workmanship expectations for industrial replacement channels. Distributors such as DigiKey, Mouser, Octopart-aggregated channels, Zouser, Xecor, and PartLocator stock authorised reels of this part for field-service bench technicians. When repairing a legacy board, technicians should verify the date code and RoHS compliance on the shipment paperwork against the original BOM. For new designs, choose the pin-compatible ADC08131CIWMX (single channel), ADC08138CIWMX (11 channels), or cross-brand AD7994BRU-0REEL (12-bit upgrade) instead, all sharing the 14-SOIC Wide package.
Recommended
Recommended Products Summary
Engineering reference data for ADC08134CIWMX — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC08134CIWM | ADC08131CIWMX | ADC08138CIWMX | AD7994BRU-0REEL | AD7993BRU-0REEL |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Analog Devices |
| Package | 14-SOIC Wide (0.295 / 7.50 mm) | 14-SOIC Wide - same | 14-SOIC Wide - same | 14-SOIC Wide - same | 14-SOIC - same | 14-SOIC - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 12 bit | 10 bit |
| Analog Input Channels | 4 | 4 | 1 | 11 | 4 | 4 |
| Conversion Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
| Serial Interface | MICROWIRE (3-wire SPI-compatible) | MICROWIRE | MICROWIRE | MICROWIRE | I2C | I2C |
| On-Chip Voltage Reference | Yes | Yes | Yes (VREFIN/VREFOUT tied internally) | Yes | Yes | Yes |
| On-Chip Track/Hold | Yes | Yes | Yes | Yes | Yes (input T/H) | Yes (input T/H) |
| Lifecycle Status | NRND | NRND | NRND | NRND | Active | Active |
Key Differentiators
- On-chip reference and track/hold in a single SOIC-14 Wide IC (vs Discrete MUX + external reference + ADC chain)
- MICROWIRE-compatible serial interface preserves 8 MCU pins vs parallel ADC (vs ADC08832IWM/NOPB)
- Pin-compatible family alternatives share SOIC-14 footprint (vs ADC08131CIWMX / ADC08138CIWMX)
- 8-bit resolution is sufficient for many process-control loops, avoiding 12-bit ADC cost premium (vs AD7994BRU-0REEL (12-bit))
Design Notes
Estimated: Use a 4-layer PCB with a continuous ground plane beneath the 14-SOIC Wide ADC footprint. Connect analog ground (GND pin 2) and reference ground (REFGND pin 8) to a single star-point on the AGND plane, separated from the digital GND beneath the serial-interface pins. Bypass V+ (pin 1) with a 10uF tantalum + 100nF ceramic pair, placed within 3 mm of the supply pin to suppress SAR switching transients.
Estimated: The SAR architecture draws short, sharp current pulses from V+ at each bit decision. Keeping V+ bypass capacitors close to pins 1 and 2 is critical because supply ringing during the MSB decision directly appears as converter error. Route SCLK with a series resistor of 33 ohm near the source if the host microcontroller is more than 25 mm away, to dampen reflections on the serial bus. Keep analog inputs short and guard-traced if VIN lines exceed 50 mm.
Estimated: Multiplexer inputs VIN0-VIN3 should be routed symmetrically with matched trace lengths to avoid introducing channel-to-channel gain/offset mismatch beyond the 8-bit quantisation step. Place the reference bypass capacitor (typically 0.1uF) directly between the VREF pin 7 and REFGND pin 8. Route CS as a dedicated chip-select line; do not tie CS low permanently or the internal state machine may interpret noise glitches as spurious conversions.
Do not skip the VREF bypass capacitor. The on-chip reference requires a stable bypass to maintain specified accuracy; an unbypassed VREF couples SAR switching noise into subsequent conversions. Avoid driving VIN inputs outside the supply rail - the analog MUX input ESD diodes will forward-conduct and distort the conversion. After power-up, allow a 1 ms reference-settling time before issuing the first CS-low to start a conversion, per TI datasheet start-up timing.
Compliance Information
RoHS compliant per TI/FindIC product page. Not AEC-Q100 qualified - not for automotive under-hood use. Lead-free and halogen-free per TI datasheet marking.
