ADS7808UB/1K - 12-Bit 100kHz Serial SAR ADC | Texas Instruments
MPN: ADS7808UB/1K ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $21.5 | $21.50 |
| 10 | $19.4 | $194.00 |
| 100 | $17.25 | $1,725.00 |
| 500 | $15.1 | $7,550.00 |
| 1,000 | $13.85 | $13,850.00 |
ADS7808UB/1K Overview
An SAR ADC is a successive-approximation-register analog-to-digital converter: it compares the sampled input against a binary-weighted internal DAC bit-by-bit in N clock cycles (here N = 12), producing a deterministic, low-latency conversion ideal for multiplexed data-acquisition, motor control feedback loops, and DSP front-ends. Within the broader taxonomy, the ADS7808UB sits at: ADC -> data converter -> signal-chain IC -> semiconductor. The 72 dB SINAD and ±½ LSB INL/DNL specifications confirm true 12-bit performance with no missing codes.
Key features include 100 kHz throughput, 72 dB SINAD at 45 kHz input, ±½ LSB integral and differential nonlinearity, six factory-trimmed input ranges (0–5 V, 0–10 V, ±5 V, ±10 V, etc.), serial data output that can be clocked from the internal oscillator or an external DSP clock, and a hardware SYNC pulse that simplifies frame alignment to standard serial ports. The reference is internal by default but may be overdriven externally for multi-channel ratio-metric systems.
Typical applications include industrial process-control front-ends, multi-channel data-acquisition boards, DSP-based vibration and motor-control signal chains, portable instrumentation, and any pin-compatible upgrade path from the older ADS7808. When designing, note that the device is pin-compatible with the 16-bit ADS7809, providing an upgrade route without PCB rework, and that the internal reference settling time influences acquisition timing at higher throughput rates.
Drop-in alternatives for ADS7808UB/1K — 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 ADS7808UB/1K (same form factor and footprint) — differing in Architecture, Package, Sampling Rate, Operating Temperature, Data Interface.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS7808UB
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7808U
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7809U
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7813UB/1K
✅ Drop-In✓ In Stock
$9.85 / Unit
View Datasheet →ADS7808UB/1K Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Architecture | SAR (Successive Approximation Register) |
| Sampling Rate | 100 kHz (10 µs conversion) |
| Number of Input Channels | 1 (single-ended, 6 software-selectable ranges) |
| SINAD | 72 dB at 45 kHz input |
| INL (Integral Nonlinearity) | ±1/2 LSB (max) |
| DNL (Differential Nonlinearity) | ±1/2 LSB (max) |
| Supply Voltage | +5 V (single supply) |
| Power Dissipation | 100 mW (max) |
| Data Interface | Serial (SPI / DSP-compatible, internal or external clock) |
| Reference | Internal 2.5 V (external overdrive supported) |
| Input Ranges | 0-5 V, 0-10 V, ±5 V, ±10 V (six factory-trimmed ranges) |
| Package | 20-pin SOIC (DW) |
| Operating Temperature | -40 °C to +85 °C (industrial) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
ADS7808UB/1K Pin Configuration
| Pin 1 | VIN — Analog input |
| Pin 2 | AGND — Analog ground |
| Pin 3 | REF — Reference input/output (internal 2.5 V) |
| Pin 4 | VANA — +5 V analog supply |
| Pin 5 | GND — Digital ground |
| Pin 6 | VDIG — +5 V digital supply |
| Pin 7 | RANGE — Input range select |
| Pin 8 | CS — Chip select (active low) |
| Pin 9 | SYNC — Frame synchronization output |
| Pin 10 | NC — Not connected (per datasheet) |
| Pin 11 | DCLOCK — Data clock input/output |
| Pin 12 | DOUT — Serial data output |
| Pin 13 | BUSY — Conversion in progress (active high) |
| Pin 14 | TAG — Tag input for channel identification |
| Pin 15 | R1IN — Range select bit 1 input |
| Pin 16 | R0IN — Range select bit 0 input |
| Pin 17 | BIP — Bipolar / unipolar select |
| Pin 18 | NC — Not connected (per datasheet) |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
Typical Applications
ADS7808UB/1K is suitable for 6 applications: Industrial Process Control Data Acquisition, DSP-Based Motor Control Feedback, Portable Test & Measurement Instrumentation, Multi-Channel Data Acquisition Systems (DAS), Medical Patient Monitoring Front-Ends, Renewable Energy / Power Inverter Telemetry.
Industrial Process Control Data Acquisition
The ADS7808UB/1K fits 4-20 mA-derived and high-level industrial signal acquisition because its six factory-trimmed input ranges (0-5 V, 0-10 V, ±5 V, ±10 V) accept standard industrial signal levels directly. Placed between a sensor front-end and an MCU/DSP, its 72 dB SINAD at 45 kHz input and ±½ LSB INL/DNL guarantee 12-bit accurate readings on multiplexed temperature, pressure, and flow channels; compared with a 16-bit ADC like ADS7809, designers save cost and code complexity while keeping pin-compatibility for future upgrades.
Recommended
DSP-Based Motor Control Feedback
With 10 µs conversion time and a hardware SYNC pulse, the ADS7808UB/1K streams feedback values into TI C2000 DSPs and similar controllers for closed-loop motor control. The serial interface can be clocked by the DSP, eliminating external glue logic and timing jitter. Compared with parallel-output ADCs, the 20-pin SOIC serial interface saves board area and pins, and 100 kHz throughput is sufficient for field-oriented control (FOC) current-sense sampling at typical PWM frequencies.
Recommended
Portable Test & Measurement Instrumentation
The ADS7808UB/1K's +5 V single-supply operation and 100 mW maximum dissipation are well-matched to handheld oscilloscopes, bench DMMs, and portable data loggers where power budget is constrained. Six input ranges cover both bench-top signal levels (10 V) and low-level transducer outputs without external scaling. The internal reference eliminates a second supply rail, and the SOIC-20 package is easy to hand-prototype - the ADS7808UB is a long-standing workhorse for compact instruments.
Recommended
Multi-Channel Data Acquisition Systems (DAS)
Although single-channel, the ADS7808UB/1K's 100 kHz throughput lets a multiplexer front-end (e.g., 16:1 MUX) scan industrial DAS boards with >6 kHz per-channel sample rate - sufficient for vibration monitoring and process control loops. The 72 dB SINAD yields effective-number-of-bits (ENOB) ≈11.7 at 45 kHz, comparable to dedicated DAS ICs. Designers moving from a single-channel ADC to a 4-channel integrated ADC (ADS6424) can keep the ADS7808UB/1K on auxiliary or backup channels for cost.
Recommended
Medical Patient Monitoring Front-Ends
The ADS7808UB/1K's industrial -40 °C to +85 °C range and ±½ LSB linearity suit ECG, SpO2, and infusion-pump front-ends where 12-bit resolution at 100 kHz adequately oversamples physiological signals (typically <1 kHz bandwidth). The serial interface simplifies isolation barrier implementation - only a few digital lines need opto-couplers, easing IEC 60601-1 compliance. Compare with the ADS131A04 for higher-precision modern medical ADC replacement designs.
Recommended
Renewable Energy / Power Inverter Telemetry
Solar inverter and battery-monitoring telemetry boards use the ADS7808UB/1K for DC-bus voltage and current-sensor digitization at 100 kHz, providing margin above typical 10-20 kHz control loops. The internal reference reduces BOM, and pin-compatibility with the 16-bit ADS7809U supports product-line SKU splits between cost-optimized 12-bit and precision 16-bit variants using a single PCB layout - a common power-converter design pattern.
Recommended
Recommended Products Summary
Engineering reference data for ADS7808UB/1K — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS7808UB | ADS7808U | ADS7809U | ADS7813UB/1K |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-pin SOIC (DW) | 20-pin SOIC (DW) - same | 20-pin SOIC (DW) - same | 20-pin SOIC (DW) - same | 20-pin SOIC (DW) - same |
| Resolution | 12 bits | 12 bits | 12 bits | 16 bits | 12 bits |
| Sampling Rate | 100 kHz | 100 kHz | 100 kHz | 100 kHz | 28 kHz |
| SINAD | 72 dB at 45 kHz | 72 dB | 72 dB | 84 dB | 72 dB |
| Supply Voltage | +5 V | +5 V | +5 V | +5 V | +5 V |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | 0 °C to +70 °C | -40 °C to +85 °C | -40 °C to +85 °C |
| Interface | Serial (SPI/DSP) | Serial | Serial | Serial | Serial |
Key Differentiators
- Pin-compatible 16-bit upgrade path on the same footprint (vs ADS8508)
- Six factory-trimmed input ranges vs typical single-range ADCs (vs ADS7813UB/1K)
- Higher throughput at identical 12-bit accuracy (vs ADS7813UB/1K)
Design Notes
Estimated: separate analog and digital ground planes with a single-point stitch under the ADS7808UB/1K to avoid digital switching noise coupling into the analog input. Decouple VANA and VDIG with 10 µF tantalum + 0.1 µF ceramic close to the pins, and route the analog input trace as a guarded differential pair on a separate analog layer.
Use the ADS7808UB/1K's BUSY pin (active high) to gate the DSP serial port; reading DOUT while BUSY is high can corrupt the conversion. The SYNC output pulse simplifies frame alignment - tie it to the DSP frame-sync input rather than relying on software timing.
Do not exceed the absolute maximum analog input voltage (±25 V transients). When switching between input ranges, allow at least one full conversion (10 µs) for the internal capacitive DAC to settle - reading immediately after a RANGE change gives erroneous codes. The internal reference needs a 10 µF bypass cap at the REF pin to meet 72 dB SINAD at full throughput.
Compliance Information
RoHS/REACH compliance confirmed by TI product page and DigiKey listing. Not AEC-Q100 qualified - this is an industrial-grade part. Halogen-free status not stated in the verified data.
