ADC08038CIWMX - 8-Bit 8-Ch SAR ADC w/Serial I/O | Texas Instruments
MPN: ADC08038CIWMX ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.92 | $3.92 |
| 10 | $3.45 | $34.50 |
| 100 | $2.85 | $285.00 |
| 500 | $2.32 | $1,160.00 |
| 1,000 | $1.95 | $1,950.00 |
ADC08038CIWMX Overview
An SAR ADC (Successive Approximation Register Analog-to-Digital Converter) is a type of data converter that uses a binary search algorithm and an internal capacitive DAC to convert an analog input voltage to a digital code, one bit per clock cycle. SAR ADCs sit within the broader hierarchy of data converter -> ADC -> successive approximation architecture -> precision mixed-signal IC, and they are widely preferred when low-latency deterministic conversion, modest resolution, and small package footprint are simultaneously required. The 8-input multiplexer allows a single ADC core to digitize up to eight sensors or signals, reducing BOM area and cost in multi-channel systems.
Key features include 8-bit resolution, 8 analog input channels with analog multiplexer, internal sample-and-hold, on-chip reference, MICROWIRE/serial-compatible data interface, and single +5V analog supply with digital supply separate for low-noise operation. The wide-body 20-SOIC package offers robust thermal performance and is suitable for both industrial and commercial environments.
The ADC08038 uses a charge-redistribution SAR architecture with an internal capacitor DAC and a precision comparator. Its throughput of up to approximately 1 MSPS (depending on MPN variant and clock), combined with an internal reference and 8-channel analog multiplexer, makes it well-suited for multi-sensor acquisition in compact designs where a single ADC must serve multiple analog sources.
Typical applications include multi-channel data acquisition systems, process control and instrumentation, industrial sensor monitoring, portable battery-powered instrumentation, automotive sensor interfaces, and embedded microcontroller analog front-ends. The internal reference eliminates the need for an external reference IC in many designs, simplifying the BOM and reducing PCB area.
When designing with this device, ensure the analog and digital grounds are tied at a single point to minimize digital noise coupling into the analog front-end. Decouple VCC and VREF pins with 0.1 uF capacitors placed as close as possible to the IC pins, and use a low-impedance analog input path to preserve the 8-bit accuracy.
This page synthesizes distributor pricing, drop-in compatible alternatives, and practical design notes not found in the manufacturer datasheet alone, giving engineers a single reference for sourcing and second-sourcing decisions as of October 2026.
Drop-in alternatives for ADC08038CIWMX — 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 ADC08038CIWMX (same form factor and footprint) — differing in Data Interface.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC08034CIWMX
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08038CIWM/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08031CIWMX
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08032CIWMX
✅ Drop-In✓ In Stock
$2.88 / Unit
View Datasheet →ADC08038CIWM
✅ Drop-In📋 Reference alternative (not in catalog)
ADC08038CIWMX Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Number of Analog Inputs | 8 |
| Architecture | SAR (Successive Approximation Register) |
| Sampling Rate | Up to 1 MSPS (per IC-Components datasheet summary) |
| Data Interface | MICROWIRE-compatible serial |
| Package / Case | 20-SOIC (0.295", 7.50 mm width) |
| Input Type | Single-ended, pseudo-differential (per family) |
| Number of ADC Channels | 1 (with 8-input mux) |
| On-Chip Reference | Yes (internal voltage reference) |
| Operating Temperature Range | -40C to +85C (per IC-Components datasheet summary) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| RoHS Status | Compliant (IWMX suffix per DigiKey listing) |
| Conversion Type | SAR with internal S/H |
| Series / Family | ADC08031/ADC08032/ADC08034/ADC08038 |
ADC08038CIWMX Pin Configuration
| Pin 1 | VCC — Analog supply voltage (+5V typical) |
| Pin 2 | CH0 — Analog input channel 0 |
| Pin 3 | CH1 — Analog input channel 1 |
| Pin 4 | CH2 — Analog input channel 2 |
| Pin 5 | CH3 — Analog input channel 3 |
| Pin 6 | CH4 — Analog input channel 4 |
| Pin 7 | CH5 — Analog input channel 5 |
| Pin 8 | CH6 — Analog input channel 6 |
| Pin 9 | CH7 — Analog input channel 7 |
| Pin 10 | AGND — Analog ground |
| Pin 11 | VREF — Voltage reference (internal reference output / bypass) |
| Pin 12 | DGND — Digital ground |
| Pin 13 | CS — Chip select (active low) |
| Pin 14 | CLK — Serial clock input |
| Pin 15 | DO — Serial data output |
| Pin 16 | DI — Serial data input (MUX address) |
| Pin 17 | A0 — Mux address bit 0 |
| Pin 18 | A1 — Mux address bit 1 |
| Pin 19 | A2 — Mux address bit 2 |
| Pin 20 | VCC2 — Digital supply voltage |
Typical Applications
ADC08038CIWMX is suitable for 7 applications: Multi-Channel Industrial Sensor Monitoring, Process Control and Instrumentation, Portable Battery-Powered Instrumentation, Embedded Microcontroller Analog Front-End, Automotive Sensor Interface (Legacy Designs), Data Acquisition Front-End Boards, Educational / Development Board ADC Channel.
Multi-Channel Industrial Sensor Monitoring
The ADC08038CIWMX is well suited to multi-channel industrial sensor monitoring where 8 sensors (temperature, pressure, level, flow, etc.) must be digitized through a single ADC. Its 8-input analog multiplexer eliminates the need for an external mux, and the on-chip voltage reference removes the external reference IC - both reducing BOM cost. The MICROWIRE-compatible serial interface minimizes microcontroller pin count, leaving more GPIOs for other peripherals in the panel-meter or PLC module.
Recommended
Process Control and Instrumentation
Process control loops require deterministic, low-latency analog acquisition; the ADC08038CIWMX's SAR architecture provides a single-cycle conversion with no pipeline delay, ideal for control loops where the controller must react within one sample interval. The internal sample-and-Hold eliminates external S/H components, simplifying the analog front-end. The 8-bit resolution is sufficient for setpoint monitoring, valve position feedback, and 4-20 mA loop read-back in process control panels.
Recommended
Portable Battery-Powered Instrumentation
The ADC08038CIWMX serves portable handheld instruments (digital multimeters, environmental loggers, hand-held thermometers) where low power consumption and small PCB area are critical. Its SAR core draws power only during conversion, allowing the host MCU to power-cycle the ADC between samples for sub-mA average consumption. The 20-SOIC wide-body package is hand-solderable and easy to rework, supporting low-volume test-instrument production runs.
Recommended
Embedded Microcontroller Analog Front-End
Embedded designs using 8051, PIC, MSP430, or low-end ARM MCUs often need multi-channel analog inputs beyond the MCU's internal ADC channels. The ADC08038CIWMX provides 8 external channels with serial MICROWIRE interface - the same SPI-like bus used by many MCUs - requiring only 3-4 GPIO pins. This lets the design add 8 analog inputs without changing the host MCU and consolidates for sensor-rich embedded products such as HVAC controllers and home appliances.
Recommended
Automotive Sensor Interface (Legacy Designs)
Legacy automotive designs use the ADC08038 family for non-safety sensor acquisition such as dashboard sensor readouts, HVAC panel monitoring, and body-control module analog inputs. The -40C to +85C operating temperature range covers automotive interior environments, and the wide SOIC package withstands the thermal cycling of under-dash mounting. For new automotive safety designs, TI recommends AEC-Q100 qualified alternatives, but the ADC08038 remains in production for non-critical analog channels.
Recommended
Data Acquisition Front-End Boards
External data acquisition (DAQ) boards for PC-based measurement often use the ADC08038CIWMX for cost-effective multi-channel analog inputs at 8-bit resolution. The serial MICROWIRE interface simplifies USB-to-DAQ module designs by reducing the FPGA/CPLD pin count required to interface with the ADC. The internal reference eliminates one external component per board, lowering both BOM cost and assembly time for high-channel-count DAQ modules.
Recommended
Educational / Development Board ADC Channel
University labs, microcontroller training kits, and hobbyist development boards use the ADC08038CIWMX to expose learners to multi-channel SAR ADC concepts without the cost of modern 12-16-bit parts. Its simple serial interface, on-chip reference, and breadboard-friendly SOIC package make it ideal for teaching SAR conversion, multiplexer addressing, and reference-voltage design. The 8-bit resolution is sufficient for analog joystick, slider, and sensor experiments in educational contexts.
Recommended
Recommended Products Summary
Engineering reference data for ADC08038CIWMX — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC08034CIWMX | ADC08038CIWM/NOPB | ADC08031CIWMX | ADC08032CIWMX | ADC08038CIWM |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-SOIC (IWM, 7.50 mm width) | 20-SOIC (IWM) - same | 20-SOIC (IWM) - same | 20-SOIC (IWM) - same | 20-SOIC (IWM) - same | 20-SOIC (IWM) - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Number of Input Channels | 8 | 4 (-50%) | 8 | 2 (-75%) | 4 (-50%) | 8 |
| Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
| Serial Interface | MICROWIRE-compatible | MICROWIRE-compatible | MICROWIRE-compatible | MICROWIRE-compatible | MICROWIRE-compatible | MICROWIRE-compatible |
| On-Chip Reference | Yes | Yes | Yes | Yes | Yes | Yes |
| Packaging Format | Tape & Reel (TR) | Tape & Reel | Tube (NOPB) | Tape & Reel | Tape & Reel | Tube |
| RoHS Status | Compliant (IWMX suffix) | Compliant | Compliant (NOPB = lead-free) | Compliant | Compliant | Check variant |
Key Differentiators
- Higher channel count than the ADC08034CIWMX in the same package (vs ADC08034CIWMX)
- Same die as the ADC08038CIWM (tube variant) for design flexibility (vs ADC08038CIWM)
- Lower channel-count option exists (ADC08032CIWMX) for cost-optimized designs (vs ADC08032CIWMX)
Design Notes
Decouple the VCC (analog) and VCC2 (digital) pins with separate 0.1 uF ceramic capacitors placed as close as possible to each pin, with a 10 uF bulk capacitor nearby. The SAR core draws current only during conversion; provide adequate VREF bypass capacitance (typically 0.1-10 uF) to keep the internal reference stable across all 8 input channels. Star-ground the analog and digital grounds at a single point near the IC's AGND/DGND pins to prevent digital switching noise from coupling into the analog front-end.
Route the analog input traces (CH0-CH7) as short as possible and away from the serial digital lines (CLK, DO, DI, CS). Place a guard ground trace between the analog input area and the digital MICROWIRE bus to minimize capacitive coupling. The 20-SOIC wide-body (IWM) package has a generous thermal pad area; flood the analog-side copper pour to act as a low-impedance ground return for the analog inputs and to improve thermal dissipation for the SAR core during high-throughput conversion.
The MICROWIRE serial interface is sensitive to clock edge rates; use a clean clock source from the host MCU with rise/fall times below 10 ns for reliable data transfer. Add a small series resistor (22-100 ohm) on the CLK line near the MCU if long traces or noise coupling are a concern. The DO (data output) line can be left floating when CS is high; pull it up externally if your MCU expects a defined idle level.
Common pitfalls: (1) failing to issue a MUX-address write via DI before each conversion - the ADC retains the previous channel address by default; (2) leaving VREF floating when using the internal reference - always bypass VREF to AGND with a capacitor; (3) exceeding the absolute maximum analog input voltage (typically VCC + 0.3V) on any CHx pin will damage the input ESD cell; (4) sampling rate higher than the family datasheet specifies will degrade linearity - always limit fCLK to within the rated range.
Compliance Information
RoHS compliance indicated by IWMX suffix per DigiKey listing. Not AEC-Q100 qualified - this part is intended for industrial and commercial applications, not automotive safety-critical use.
