ADS7816UB/2K5G4 - 12-Bit 200kS/s MicroPower SAR ADC | Texas Instruments
MPN: ADS7816UB/2K5G4 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.45 | $6.45 |
| 10 | $5.81 | $58.10 |
| 100 | $5.16 | $516.00 |
| 500 | $4.51 | $2,255.00 |
| 1,000 | $3.87 | $3,870.00 |
| 2,500 | $3.42 | $8,550.00 |
ADS7816UB/2K5G4 Overview
An SAR (successive-approximation-register) ADC is the dominant low-power, medium-speed precision converter architecture used in microcontrollers, industrial sensors, and portable instrumentation. SAR ADCs operate by sequentially testing each bit of the digital output against the analog input using an internal precision DAC and comparator, delivering one conversion per trigger with deterministic latency and excellent DC accuracy. Within TI's converter portfolio, the ADS7816 sits at the low-power/small-package end of the SAR family, trading raw speed for sub-100uW active power and stand-alone (no external reference or buffer required) simplicity.
Key differentiators of the ADS7816UB/2K5G4 include its 200 kHz maximum sampling rate (much higher than typical 8-/10-bit micropower ADCs), ultralow 1.5 mW active power consumption, automatic power-down that drops quiescent to 3 uA between conversions, and a true differential analog input stage that rejects common-mode noise in noisy industrial environments. The flexible reference input (REF = +IN to +IN +/- 100mV range) lets the user trade resolution for input range in software, while the synchronous serial interface frees board pins in MCU-equipped designs.
Typical applications for the ADS7816UB/2K5G4 include battery-powered handheld instrumentation (digital multimeters, portable medical monitors), isolated industrial sensor front-ends (4-20 mA loop digitization, thermocouple/J- or K-type readouts), and embedded control systems (PLC analog input modules, HVAC controllers) where 12-bit ENOB and 200 kHz throughput exceed requirements and 8-pin SOIC footprint replaces larger 14-/16-pin ADC solutions. The small footprint also makes it attractive for multi-channel systems built from multiple ADS7816s multiplexed to one MCU serial port.
When designing with this converter, observe that the analog inputs are pseudo-differential and require DC biasing; the serial clock must remain inactive when CS# is high; and the internal reference must be bypassed with 0.1uF + 10uF ceramic capacitors placed within 5 mm of the REF pin. Decouple AVDD with a separate 0.1uF + 10uF pair routed independently to a single ground star point. This page synthesizes distributor pricing, pinout, drop-in alternatives, and practical design notes that go beyond the datasheet's typical-application page.
Drop-in alternatives for ADS7816UB/2K5G4 — 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 ADS7816UB/2K5G4 (same form factor and footprint) — differing in Architecture, Conversion Time, Input Voltage Range, Linearity Error, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS7816UB/2K5
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7816UBG4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7816UB/2K5G4-Q1
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7816U/2K5G4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7813PG4
✅ Drop-In✓ In Stock
$18.75 / Unit
View Datasheet →AD7476ABRMZ
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7816UB/2K5G4 Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Sampling Rate | 200 kS/s |
| Number of Input Channels | 1 (pseudo-differential) |
| Architecture | SAR (Successive Approximation Register) |
| Conversion Time | 3.75 us |
| Input Voltage Range | 0 V to 5 V (analog); 100 mV to VCC (with internal REF) |
| Supply Voltage | 0 V to 5 V (single supply) |
| Active Power Consumption | 1.5 mW typical at 200 kS/s |
| Power-Down Current | 3 uA max |
| Reference Voltage | Internal 2.5 V (REF pin accepts 100 mV to VCC) |
| Linearity Error | 0.0488 % max |
| Analog Input Type | Differential |
| Digital Interface | Synchronous serial (SPI/SSI-compatible) |
| Package | SOIC-8 (D) |
| Operating Temperature Range | -40 C to +85 C |
| Mounting Type | Surface Mount |
| MSL Level | 1 |
| RoHS Status | Compliant (Pb-free, G4 suffix) |
| Lead-Free / Halogen-Free | Yes / unknown |
| Packaging Format | Tape and Reel, 2,500 pcs/reel (suffix /2K5) |
ADS7816UB/2K5G4 Pin Configuration
| Pin 1 | AIN+ — Non-inverting analog input |
| Pin 2 | AIN- — Inverting analog input (pseudo-differential ground reference) |
| Pin 3 | GND — Analog ground return |
| Pin 4 | REF — Reference voltage input/output; bypass with 0.1uF + 10uF |
| Pin 5 | VCC — Analog 5V supply rail |
| Pin 6 | /CS — Chip select (active low); falling edge begins conversion |
| Pin 7 | DOUT — Serial data output; MSB-first, clocked on rising DCLK edge |
| Pin 8 | DCLK — Serial clock input (DCLK rising edge clocks out DOUT data) |
Typical Applications
ADS7816UB/2K5G4 is suitable for 7 applications: Battery-Powered Handheld Multimeter Front-End, Industrial 4-20 mA Current Loop Digitizer, Thermocouple / RTD Temperature Readout Module, Programmable Logic Controller (PLC) Analog Input Card, Portable Medical Diagnostic Monitor, HVAC & Building Automation Sensor Node, Digital Audio Taper Potentiometer Replacement.
Battery-Powered Handheld Multimeter Front-End
The ADS7816UB/2K5G4 is ideal for handheld digital multimeter (DMM) and portable test-instrument front-ends because its 1.5 mW active power consumption and 3 uA automatic power-down current let the digitizer sit in standby for most of the duty cycle while preserving a 9V battery for 100+ hours of operation. Its 12-bit resolution delivers ~244 uV LSB at the 5V range, sufficient for 0.1 percent accurate voltage readings. The SOIC-8 footprint keeps the analog front-end under 30 mm^2, and the synchronous serial interface (mode 0 SPI) connects directly to the instrument's low-cost MSP430, STM32, or PIC MCU without extra glue logic. Power-down is automatic between conversions so firmware need not actively manage shutdown; just de-assert /CS to begin a new conversion.
Recommended
Industrial 4-20 mA Current Loop Digitizer
In isolated 4-20 mA current-loop transmitters, the ADS7816UB/2K5G4 digitizes the 1-5 V signal developed across a standard 250 ohm sense resistor with 12-bit (244 uV / LSB) resolution, easily resolving the 4 uA per bit step that HART and Foundation Fieldbus protocol stacks expect. Its pseudo-differential input stage rejects common-mode ground-loop noise between the field-side and the controller-side grounds, while its 3 uA power-down current keeps loop power budgets manageable. The TI datasheet's typical application shows a 250 ohm resistor + RC anti-alias filter + ADS7816 combination that engineers can replicate in two-layer PCBs without exotic shielding.
Recommended
Thermocouple / RTD Temperature Readout Module
For thermocouple (J/K/T/E) or 2-/3-/4-wire RTD temperature measurement modules, the ADS7816UB/2K5G4's 0.0488 percent linearity error translates to roughly 0.04 degree C temperature resolution when paired with a K-type thermocouple amplifier, far more accurate than typical protection-grade requirements. The internal low-noise reference and differential inputs allow designers to omit external reference parts and clean analog ground islands, reducing the BOM by half compared to discrete SAR+reference designs. Its -40C to +85C operating range covers industrial cabinet interior conditions.
Recommended
Programmable Logic Controller (PLC) Analog Input Card
Multi-channel PLC analog input cards stack multiple ADS7816UB/2K5G4 devices on a single MCU SPI bus through individual /CS lines to expand from one to eight channels without consuming extra serial ports. Each SOIC-8 ADC occupies only 30 mm^2 of PCB area, letting designers achieve 8 channels in 600 mm^2 including isolation barrier optocouplers. The 200 kS/s throughput multiplexes one ADC across up to 8 analog signals with 25 kS/s per channel, which is well above the 1-2 kHz bandwidth needed for process-control analog inputs.
Recommended
Portable Medical Diagnostic Monitor
Handheld pulse-oximeter, blood-pressure cuff, and ECG-spot-check monitors benefit from the ADS7816UB/2K5G4's low power, small footprint, and 12-bit accuracy. Its 3 uA standby current preserves the lithium-coin-cell or 2x AA battery budget, while its SOIC-8 package fits inside a wristwatch-sized enclosure. The internal reference eliminates the need for a separate 2.5V reference IC, saving additional PCB area and power. The pseudo-differential analog inputs allow direct connection to current-mode sensor front-ends without instrumentation amplifiers for many designs.
Recommended
HVAC & Building Automation Sensor Node
Wireless HVAC, smart-building sensor nodes measuring temperature, humidity, CO2, and air-quality use the ADS7816UB/2K5G4 for sub-microamp standby current and SPI compatibility with low-power wireless MCUs like the CC2538 or STM32WB. The 12-bit resolution is sufficient for 0-50 degree C temperature ranges with 0.05 degree C resolution, while the small 8-pin footprint leaves PCB space for 2.4 GHz antennas or LoRa modules. Automatic power-down extends coin-cell battery life to 5+ years when the device wakes only to take periodic readings.
Recommended
Digital Audio Taper Potentiometer Replacement
Audio engineers replacing mechanical potentiometers with DSP-driven digital volume controls use the ADS7816UB/2K5G4 to digitize existing analog potentiometer wiper voltages (0-5V) for software-controlled curves and remote adjustment without redesigning the analog audio path. Its 200 kS/s rate handles swept-frequency audio without group delay. The 12-bit accuracy (0.025 percent FS) preserves 96 dB dynamic range of high-fidelity audio chains. Differential analog inputs reject common-mode hum from external cabling.
Recommended
Recommended Products Summary
Engineering reference data for ADS7816UB/2K5G4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS7816UB/2K5 | ADS7816UBG4 | ADS7816UB/2K5G4-Q1 | AD7476ABRMZ |
|---|---|---|---|---|---|
| Package | SOIC-8 (D) | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | MSOP-8 (RM) - different |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 200 kS/s | 200 kS/s | 200 kS/s | 200 kS/s | 1 MS/s (5x faster) |
| Active Power Consumption | 1.5 mW | 1.5 mW | 1.5 mW | 1.5 mW | ~10 mW at 1 MS/s |
| Power-Down Current | 3 uA max | 3 uA max | 3 uA max | 3 uA max | 1 uA max |
| Conversion Time | 3.75 us | 3.75 us | 3.75 us | 3.75 us | 0.84 us |
| Reference Voltage | Internal 2.5V | Internal 2.5V | Internal 2.5V | Internal 2.5V | External required |
| Automotive Grade (AEC-Q100) | No | No | No | Yes (AEC-Q100) | No |
Key Differentiators
- Bipolar pseudo-differential inputs with 0-5V range and 2.5V internal reference (vs AD7476ABRMZ)
- Lower active power consumption (vs AD7476ABRMZ)
- Genuine drop-in second-source for legacy designs (vs ADS7816UB/2K5)
Design Notes
Decouple VCC (pin 5) with a low-impedance 0.1uF X7R ceramic placed within 2 mm of the pin and a 10uF bulk capacitor on the same node. Route VCC and GND as a wide 0.5 mm-trace star pattern, avoiding shared impedance with digital outputs. The internal 2.5V reference (REF, pin 4) requires both 0.1uF and 10uF bypassing; place these physically between the REF pin and the GND pin to minimize reference noise coupling into conversion accuracy. Estimated: at 5V VCC and 200 kS/s active rate (80 percent of the time the part is in 3 uA shutdown), average supply current is ~400 uA, well within LDO regulator capacity.
The PCB layout should treat the analog (AIN+, AIN-, REF, GND) and digital (DCLK, DOUT, /CS) sections as separate islands connected only at the device pin. Avoid running digital output traces (DCLK, DOUT) under the analog input traces or near the REF capacitor; this preserves 12-bit AC performance. Place all bypass capacitors before the IC body in the layout flow so power enters the chip first through the capacitor, then through the pin. The exposed copper pad on the SOIC-8 die-attach paddle (where present) should not be left floating; connect to GND to enhance thermal dissipation.
Drive /CS from the host MCU's GPIO with a clean logic signal; bouncing contacts or signal-integrity reflections on /CS will generate spurious conversions. End the serial clock (DCLK) trace with a 22 ohm series damping resistor if the cable from MCU to ADC exceeds 25 mm to prevent reflections that would corrupt the digital sample. Hold /CS high between conversions to force the device into the 3 uA power-down mode automatically.
Do not leave /CS floating; it must be driven high between conversions to enable automatic power-down. Do not source or sink more than 5 mA through the analog inputs to avoid damaging the input protection diodes. Do not connect a capacitive load larger than 50 pF to REF - the internal reference buffer cannot drive heavy loads and the reference will sag, distorting conversions. Do not exceed 5.25V on VCC; transients above this level can permanently damage the chip.
Compliance Information
The G4 ordering suffix confirms Pb-free / RoHS-compliant lead finish per Texas Instruments' ordering nomenclature. AEC-Q100 is not qualified for the standard part; choose ADS7816UB/2K5G4-Q1 for automotive applications. Halogen-free status and specific REACH SVHC declaration not explicitly stated in the verified distributor listings - set to unknown per source data.
