ADS8481IBRGZR - 18-Bit 1MSPS SAR ADC w/Ref | Texas Instruments
MPN: ADS8481IBRGZR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.85 | $168.50 |
| 100 | $14.95 | $1,495.00 |
| 500 | $13.2 | $6,600.00 |
| 1,000 | $11.75 | $11,750.00 |
ADS8481IBRGZR Overview
What is a SAR ADC? A successive-approximation-register analog-to-digital converter is a precision data-acquisition IC that resolves an analog input one bit at a time using a comparator, a DAC, and a binary search register, completing a full conversion in N clock cycles. SAR ADCs sit in the broader hierarchy of precision converters (SAR -> ADC -> data converter -> signal chain IC -> semiconductor), offering the best trade-off of speed, resolution, and power for many industrial and instrumentation applications, since they require no pipeline latency.
Key features of the ADS8481IBRGZR include ±0.6 LSB typical INL/DNL, 87 dB SNR, no missing codes over the full industrial -40 °C to +85 °C range, internal 4.096 V low-drift reference, and a true 18-bit parallel data bus. The wide 1 MSPS sampling rate makes it suitable for high-throughput multichannel systems through external multiplexer switching.
Architecturally, the part uses a charge-redistribution DAC array, an inherent sample-and-hold, and an internal clock. The pseudo-differential input structure simplifies front-end signal conditioning while preserving good common-mode rejection; it also simplifies PCB layout by reducing the number of true differential traces required.
Typical applications include industrial process control, medical instrumentation, vibration analysis, optical encoders, and high-speed data acquisition systems. The part also fits next-generation logic-instrumentation designs where low noise and high DC accuracy are required.
When designing with this device, place the decoupling capacitors (10 µF tantalum + 0.1 µF ceramic) within a few millimeters of the supply pins and provide a solid ground plane under the exposed pad. To preserve 18-bit accuracy, the reference decoupling capacitor and the input common-mode bypass must be low-ESR ceramic parts placed near the relevant pins.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for ADS8481IBRGZR — 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 ADS8481IBRGZR (same form factor and footprint) — differing in Package, Architecture, Resolution, Input Type, Data Interface.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS8481IBRGZT
✅ Drop-In📋 Reference alternative (not in catalog)
ADS8481IRGZRG4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS8481IRGZRQ1Q1
✅ Drop-In📋 Reference alternative (not in catalog)
ADS8482IBRGZR
✅ Drop-In✓ In Stock
$14.45 / Unit
View Datasheet →ADS8472IRGZR
✅ Drop-In✓ In Stock
$8.5 / Unit
View Datasheet →AD7983BCPZ-R2
✅ Drop-In✓ In Stock
$6.35 / Unit
View Datasheet →ADS8481IBRGZR Maximum Ratings & Electrical Characteristics
| Resolution | 18 bits |
| Sample Rate | 1 MSPS |
| Number of Channels | 1 |
| Architecture | SAR (Successive Approximation Register) |
| Input Type | Pseudo-Differential Unipolar Single-Ended |
| Data Interface | Parallel (18-bit, 16-bit, or 8-bit bus modes) |
| Analog Supply Voltage | 4.75 V to 5.25 V |
| Digital I/O Supply | 2.7 V to 5.25 V |
| Internal Reference Voltage | 4.096 V |
| Offset Error | ±0.1 mV (over temperature) |
| INL (Max) | ±1.5 LSB |
| DNL (Max) | ±1 LSB (no missing codes) |
| SNR | 87 dB (typical) |
| Operating Temperature | -40 °C to +85 °C |
| Package | 48-VQFN (RGZ) 7x7 mm with exposed thermal pad |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ADS8481IBRGZR 48-vqfn (rgz) 7x7 mm with exposed thermal pad Pin Configuration Guide
Pin configuration for ADS8481IBRGZR (48-vqfn (rgz) 7x7 mm with exposed thermal pad package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for ADS8481IBRGZR.
Refer to the datasheet for full pin configuration.
Typical Applications
ADS8481IBRGZR is suitable for 6 applications: Industrial Process Control & Data Acquisition, Medical Instrumentation Front-End, Vibration & Condition Monitoring, Optical Encoder & Position Sensing, Portable Test & Measurement, Next-Generation Logic Instrumentation & Bench DMMs.
Industrial Process Control & Data Acquisition
The ADS8481IBRGZR's 18-bit resolution, 1 MSPS throughput, and ±0.1 mV offset error over -40 °C to +85 °C make it well suited to industrial process-control front-ends reading 4-20 mA or ±10 V signals through a front-end instrumentation amp. Its internal 4.096 V reference eliminates the need for a precision external reference, simplifying BOM cost, while the 48-VQFN (RGZ) footprint allows dense multi-channel layouts when paired with external analog multiplexers for 8-/16-channel systems.
Recommended
Medical Instrumentation Front-End
The ADS8481IBRGZR's 18-bit resolution and 87 dB SNR deliver the dynamic range required by medical instrumentation such as patient-monitoring DSP chains, infusion-pump dosing feedback, and bedside-monitoring analog front ends. The integrated 4.096 V reference reduces analog complexity and PCB area, while the parallel interface minimizes conversion latency in real-time signal-processing loops. Operating from a single +5 V analog supply simplifies medical-grade isolation design.
Recommended
Vibration & Condition Monitoring
With 1 MSPS sampling and 87 dB SNR, the ADS8481IBRGZR captures the harmonic content of vibration sensors in motor-control and rotating-machinery condition-monitoring applications. The pseudo-differential input pairs cleanly with IEPE piezoelectric accelerometers through a simple bias network, and the 18-bit no-missing-codes performance preserves measurement fidelity for FFT-based spectral analysis across the industrial temperature range.
Recommended
Optical Encoder & Position Sensing
The ADS8481IBRGZR's 18-bit resolution enables precise absolute-encoder readout in servo drives, CNC machine tools, and robotic position sensors. Its 1 MSPS throughput supports high-velocity tracking, while the parallel bus minimizes read latency for closed-loop control loops. The wide industrial temperature range and ±0.1 mV offset stability keep encoder accuracy consistent across warm-up drift and shop-floor thermal swings.
Recommended
Portable Test & Measurement
The ADS8481IBRGZR's micropower sampling architecture and internal reference make it a fit for portable test-and-measurement instruments such as handheld oscilloscope daughter-boards, multimeter analog boards, and field-service diagnostics. The 48-VQFN (RGZ, 7x7 mm) footprint allows compact PCB designs, while the parallel interface supports direct connection to an FPGA or DSP for real-time waveform analysis without the latency of a serial ADC.
Recommended
Next-Generation Logic Instrumentation & Bench DMMs
The ADS8481IBRGZR's 18-bit 1 MSPS performance suits next-generation logic-instrumentation designs where a precision SAR ADC is paired with a host FPGA or microcontroller for digital readouts. The parallel 18/16/8-bit bus modes ease integration with legacy 8-bit microcontrollers and modern 32-bit processors alike, while the exposed thermal pad simplifies thermal management in high-density bench-instrument chassis.
Recommended
Recommended Products Summary
Engineering reference data for ADS8481IBRGZR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS8481IBRGZT | ADS8481IRGZRG4 | ADS8481IRGZRQ1Q1 | ADS8482IBRGZR | ADS8472IRGZR | AD7983BCPZ-R2 |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Package | 48-VQFN (RGZ) 7x7 mm | 48-VQFN (RGZ) 7x7 mm - same | 48-VQFN (RGZ) 7x7 mm - same | 48-VQFN (RGZ) 7x7 mm - same | 48-VQFN (RGZ) 7x7 mm - same | 48-VQFN (RGZ) 7x7 mm - same | 48-LFCSP (QFN-class) - same footprint family |
| Resolution | 18 bits | 18 bits | 18 bits | 18 bits | 18 bits | 16 bits | 18 bits |
| Sample Rate | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS | 2 MSPS | 1 MSPS | 1 MSPS |
| Channels | 1 (single) | 1 | 1 | 1 | 1 | 2 (dual simultaneous) | 1 |
| Internal Reference | 4.096 V | 4.096 V | 4.096 V | 4.096 V | 4.096 V | External (no internal) | External (no internal) |
| Data Interface | Parallel (18/16/8-bit) | Parallel | Parallel | Parallel | Parallel | Parallel | Serial SPI/QSPI/MICROWIRE |
| Automotive Grade (AEC-Q100) | No (industrial) | No | No | Yes (AEC-Q100) | No | No | No |
Key Differentiators
- Internal 4.096 V low-drift reference (vs AD7983BCPZ-R2)
- Parallel interface supports legacy 8-bit microcontrollers (vs AD7983BCPZ-R2)
- Automotive grade variant available in same package (vs ADS8472IRGZR)
- Higher-precision 18-bit resolution in dual-channel footprint class (vs ADS8472IRGZR)
Design Notes
Place a 10 µF tantalum and a 0.1 µF ceramic decoupling capacitor within 5 mm of the analog supply pin (AVDD) and the digital supply pin (DVDD); this keeps the charge-redistribution DAC's high-frequency switching transients away from the input front end. Solder the exposed thermal pad (EP) to a continuous ground plane with at least 8 thermal vias to the inner ground layer - this also reduces ground bounce on the parallel data bus at 1 MSPS. Keep the REF decoupling capacitor (1 µF to 10 µF low-ESR ceramic) within 3 mm of the REFIN/REFOUT pin.
Route the 18-bit parallel data bus (DB0-DB17) as matched-length groups (LSB nibble, MSB nibble, byte-2) so that bus skew stays within the tDLY timing margin at 1 MSPS. Place a ground guard trace between the analog input traces (IN+, IN-) and the digital bus to reduce digital-to-analog crosstalk. Keep the analog input traces short and symmetric - the pseudo-differential input still benefits from matched trace impedance.
Do not exceed the maximum analog supply of 5.25 V or drop below 4.75 V - the internal reference and charge-redistribution DAC are calibrated at 5 V and accuracy degrades outside this range. Avoid switching the BUSY line mid-conversion; the host must wait for the BUSY rising edge before clocking the next CONVST pulse. For high-precision designs, add a software self-calibration cycle at power-up and after any supply-voltage change of more than 2%.
Estimated: at 1 MSPS with an 18-bit bus, the switching-induced digital current on DVDD reaches ~10 mA peak; using a ferrite bead between AVDD and DVDD or a separate LDO for the digital supply reduces digital-to-analog noise coupling. Place a small RC snubber (10 Ω + 100 pF) on the CONVST pin at the source if long CONVST traces cause ringing into the SAR comparator.
Compliance Information
RoHS compliant per TI product page; the ADS8481IBRGZR is industrial (-40 °C to +85 °C), not automotive qualified. For AEC-Q100 applications use the ADS8481IRGZRQ1Q1 which is pin-compatible. REACH and conflict-minerals statements available on TI's compliance portal.
