ADS8345NB/1KG4 - 16-Bit 8-Ch 100kSPS SAR ADC | Texas Instruments
MPN: ADS8345NB/1KG4 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.92 | $8.92 |
| 10 | $7.96 | $79.60 |
| 100 | $6.85 | $685.00 |
| 500 | $5.78 | $2,890.00 |
| 1,000 | $4.92 | $4,920.00 |
ADS8345NB/1KG4 Overview
A SAR ADC is a successive-approximation register analog-to-digital converter that performs a binary search through an internal capacitive DAC to resolve each conversion cycle in a fixed number of clock cycles. SAR ADCs combine low-latency (no pipeline delay), low power, and excellent DC accuracy, which places them in the hierarchy of: ADC -> SAR ADC -> data converter -> signal chain IC -> semiconductor. This makes the ADS8345 ideally suited for multiplexed multi-channel data acquisition where fast channel switching and deterministic latency are required.
Key features of the ADS8345NB/1KG4 include a wide 2.7 V to 5.25 V single supply range, a bipolar input range with reference voltage (VREF) variable from 500 mV to VCC/2, a low-power shutdown mode (typical 0.5 uA), and pin-for-pin compatibility with the ADS7844 and ADS8344. The 20-SSOP package provides a compact footprint suitable for high-density PCB designs, and the operating temperature range of -40C to +85C supports industrial environments.
Architecturally, the ADS8345NB integrates an 8-channel analog input multiplexer, a high-performance SAR core with internal clock, a programmable reference input, and an SPI-compatible serial interface. The reference input supports ratiometric measurements when paired with an external reference and ADC excitation source, simplifying bridge-sensor and thermistor designs.
Typical applications of the ADS8345NB/1KG4 include data acquisition systems, test and measurement equipment, industrial process control, personal digital assistants, and battery-operated portable multi-channel data loggers. The low 8 mW typical power and 0.5 uA shutdown current also make it well-suited for handheld instrumentation.
When designing with this ADC, ensure the analog and digital grounds are tied at a single point near the ADC and that VREF is decoupled with both a 10 uF bulk and a 0.1 uF ceramic capacitor. For ratiometric measurements, use a low-impedance reference to avoid gain errors at full throughput.
This page synthesizes distributor pricing, drop-in-compatible pin-to-pin alternatives, and practical design guidance not available on the manufacturer datasheet, giving engineers a single reference for selecting, sourcing, and laying out the ADS8345NB/1KG4.
Drop-in alternatives for ADS8345NB/1KG4 — 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 ADS8345NB/1KG4 (same form factor and footprint) — differing in Input Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS8344NB/1KG4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS8345NB/1K
✅ Drop-In✓ In Stock
$7.85 / Unit
View Datasheet →ADS8345NB
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ADS8345
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ADS8344NB
✅ Drop-In📋 Reference alternative (not in catalog)
ADS8345NB/1KG4 Maximum Ratings & Electrical Characteristics
| Resolution | 16 bits |
| Number of Input Channels | 8 single-ended / 4 differential |
| Architecture | SAR (Successive Approximation) |
| Sampling Rate | 100 kSPS (max) |
| Input Type | Single-ended, differential, bipolar |
| Supply Voltage | 2.7 V to 5.25 V (single) |
| Reference Voltage | 500 mV to VCC/2 |
| SINAD | 85 dB |
| Power Dissipation (typ) | 8 mW at 100 kHz, +5 V |
| Shutdown Current (typ) | 0.5 uA |
| Conversion Time | 6.66 us typical |
| Linearity Error | 0.0092 % (max) |
| Interface | Serial (SPI/QSPI/MICROWIRE compatible) |
| Package | 20-SSOP |
| Operating Temperature | -40C to +85C |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ADS8345NB/1KG4 Pin Configuration
| Pin 1 | VREF — Reference voltage input (500 mV to VCC/2) |
| Pin 2 | +VCC — Power supply (2.7 V to 5.25 V) |
| Pin 3 | CH0 — Analog input channel 0 |
| Pin 4 | CH1 — Analog input channel 1 |
| Pin 5 | CH2 — Analog input channel 2 |
| Pin 6 | CH3 — Analog input channel 3 |
| Pin 7 | CH4 — Analog input channel 4 |
| Pin 8 | CH5 — Analog input channel 5 |
| Pin 9 | CH6 — Analog input channel 6 |
| Pin 10 | CH7 — Analog input channel 7 |
| Pin 11 | COM — Common analog input reference |
| Pin 12 | GND — Ground |
| Pin 13 | SHDN — Shutdown control input (active low) |
| Pin 14 | DOUT — Serial data output |
| Pin 15 | DIN — Serial data input |
| Pin 16 | CS — Chip select (active low) |
| Pin 17 | DCLK — Serial data clock |
| Pin 18 | BUSY — ADC busy output |
| Pin 19 | GND — Digital ground |
| Pin 20 | NC — Not connected (per datasheet) |
Typical Applications
ADS8345NB/1KG4 is suitable for 6 applications: Industrial Data Acquisition Systems, Test and Measurement Equipment, Personal Digital Assistants and Portable Instruments, Industrial Process Control Systems, Battery-Operated Multi-Channel Data Loggers, Medical and Instrumentation Front-Ends.
Industrial Data Acquisition Systems
The ADS8345NB/1KG4 fits industrial data acquisition (DAQ) systems because its 16-bit resolution, 85 dB SINAD, and 8 single-ended / 4 differential input channels allow direct connection of thermocouples, RTDs, and 4-20 mA current loops through simple front-end conditioning. The 100 kSPS throughput multiplexes 8 channels at 12.5 kSPS each, sufficient for closed-loop process control and SCADA monitoring. With a single 2.7-5.25 V supply, the ADC is compatible with both 3.3 V MCU-based designs and 5 V PLC analog input cards. Pin-for-pin compatibility with the ADS7844/ADS8344 also enables easy upgrade from 12-bit legacy systems.
Recommended
Test and Measurement Equipment
In test and measurement equipment such as benchtop multimeters, oscilloscope auxiliary ADCs, and data loggers, the ADS8345NB/1KG4 provides 16-bit resolution and 85 dB SINAD for accurate capture of wide-dynamic-range signals. The 100 kSPS sampling rate is sufficient for audio-bandwidth and slow-transient measurements. The 2.7-5.25 V single supply is ideal for portable handheld instruments, where 0.5 uA shutdown current extends battery life during standby. The synchronous serial interface is compatible with most microcontrollers and DSPs, simplifying integration into PCIe-based digitizer cards.
Recommended
Personal Digital Assistants and Portable Instruments
The ADS8345NB/1KG4 is recommended for personal digital assistants (PDAs) and portable instruments because of its 8 mW typical power dissipation at 100 kHz throughput with +5 V supply, plus a 0.5 uA shutdown mode for idle periods. Per the TI datasheet, this combination makes the part especially attractive for battery-operated systems. The 8-channel input MUX allows direct connection of multiple sensor types (temperature, pressure, position) without an external analog switch. The SSOP-20 footprint fits compact handheld enclosures, and the 2.7 V minimum supply supports single-cell Li-ion operation.
Recommended
Industrial Process Control Systems
Process control applications such as PLC analog input modules, distributed control system (DCS) I/O, and valve actuators benefit from the ADS8345NB/1KG4's 85 dB SINAD and 0.0092% maximum linearity error per the TI datasheet. The wide 2.7-5.25 V supply tolerance handles industrial 24 V->5 V post-regulation rails with significant ripple. The -40C to +85C operating range meets industrial temperature specifications for outdoor cabinets and factory-floor installations. The 8-channel MUX reduces PCB area compared to discrete ADC-per-channel designs, lowering BOM cost and improving reliability.
Recommended
Battery-Operated Multi-Channel Data Loggers
Battery-operated multi-channel data loggers for environmental monitoring, fleet telematics, and remote sensor telemetry use the ADS8345NB/1KG4 because of its 0.5 uA shutdown current and 8 mW active power per TI datasheet specifications. The 8-channel MUX captures multiple sensors (temperature, humidity, voltage, current) into a single ADC, reducing sleep-mode system current during slow sample intervals. The 100 kSPS burst mode supports fast-trigger event capture while preserving average power budget. An SPI-compatible interface allows direct DMA-driven readout to low-power MCUs like the MSP430.
Recommended
Medical and Instrumentation Front-Ends
Medical and instrumentation front-ends such as patient monitors, blood glucose meters, and benchtop analyzers leverage the ADS8345NB/1KG4's 16-bit resolution and 85 dB SINAD for accurate capture of low-amplitude biopotential and electrochemical signals. The 8-channel MUX supports multi-parameter monitors (ECG, SpO2, temperature, respiration) from a single ADC, simplifying medical device PCBs. The bipolar input range with external reference allows direct interfacing to bridge-type pressure sensors and strain gauges used in infusion pumps. The synchronous serial interface provides electrical isolation via digital isolators for patient-connected equipment.
Recommended
Recommended Products Summary
Engineering reference data for ADS8345NB/1KG4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS8344NB/1KG4 | ADS8345NB/1K | ADS8345NB | ADS8345 | ADS7828E/250 |
|---|---|---|---|---|---|---|
| Package | 20-SSOP | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same | 20-SSOP - same | 16-TSSOP - different |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 16 bits | 12 bits | 16 bits | 16 bits | 16 bits | 12 bits |
| Sampling Rate | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 200 kSPS |
| Number of Channels | 8 SE / 4 DIFF | 8 SE / 4 DIFF | 8 SE / 4 DIFF | 8 SE / 4 DIFF | 8 SE / 4 DIFF | 8 SE / 8 DIFF (I2C) |
| Supply Voltage | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V |
| Interface | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | I2C (different protocol) |
Key Differentiators
- Pin-for-pin compatible with 12-bit ADS7844/ADS8344 for easy 16-bit upgrades (vs ADS8344NB/1KG4)
- Tape-and-reel /1KG4 packaging supports high-volume automated assembly (vs ADS8345NB (bulk))
- Wide 2.7-5.25 V single supply supports 3.3 V and 5 V designs (vs ADS7828E/250)
Design Notes
Estimated: For best 16-bit accuracy, place a 10 uF bulk + 0.1 uF ceramic decoupling capacitor as close as possible to the +VCC pin (pin 2), and a separate 10 uF + 0.1 uF pair on the VREF pin (pin 1). Keep analog input traces (CH0-CH7, COM) away from digital lines (CS, DCLK, DOUT, DIN, BUSY) on the PCB layer stack-up to minimize digital crosstalk. Use a single-point ground connection between analog and digital ground planes near the ADC.
Do not allow the analog input voltage on any CHx pin to exceed VCC + 0.3 V or go below GND - 0.3 V, as the input protection diodes will forward-bias and corrupt the conversion. Per the TI datasheet, the reference voltage VREF must remain within 500 mV to VCC/2, with VREF less than VCC. For ratiometric measurements, drive VREF and the bridge excitation from the same low-impedance source to cancel reference drift errors.
Estimated: The DCLK clock should be driven from a clean CMOS source with minimal rise/fall times (under 10 ns) to avoid double-clocking the ADC. Add a 10-100 ohm series damping resistor near the DCLK pin if long PCB traces or cable connections introduce ringing. Keep DCLK routing short and adjacent ground-trace shielded to minimize reflections. The BUSY signal should be monitored to avoid starting a new conversion before the previous one completes.
Compliance Information
RoHS and lead-free compliant per Texas Instruments product page. Not AEC-Q100 qualified (industrial grade only); not automotive qualified. Reach compliance per TI environmental statement.
