Overview
The ADS8685IPWR, produced by Texas Instruments, is a high-performance, 16-bit successive approximation register (SAR) analog-to-digital converter (ADC) with an integrated analog front-end. This device is part of the ADS868x family, which includes the ADS8681 and ADS8689, each offering different conversion speeds. The ADS8685IPWR operates at a conversion rate of 500 kSPS, making it suitable for a variety of high-speed data acquisition applications.
The device features software-programmable input ranges, both bipolar and unipolar, and operates on a single 5-V analog supply with a 1.65-V to 5-V I/O supply. It includes an on-chip 4.096-V reference with low drift and offers excellent performance metrics such as differential nonlinearity (DNL) and integral nonlinearity (INL) of ±0.4 LSB and ±0.5 LSB, respectively. The ADS8685IPWR also includes input overvoltage protection up to ±20 V and a high resistive input impedance of ≥ 1 MΩ.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Resolution | 16 Bits | - |
| Conversion Rate | 500 kSPS | - |
| Input Ranges (Bipolar) | ±12.288 V, ±10.24 V, ±6.144 V, ±5.12 V, ±2.56 V | V |
| Input Ranges (Unipolar) | 0 V–12.288 V, 0 V–10.24 V, 0 V–6.144 V, 0 V–5.12 V | V |
| Analog Supply Voltage | 4.75–5.25 V | V |
| Digital Supply Voltage | 1.65–3.3 V | V |
| Input Impedance | ≥ 1 MΩ | Ω |
| Signal-to-Noise Ratio (SNR) | 90.5 dB | dB |
| Total Harmonic Distortion (THD) | –112 dB | dB |
| Operating Temperature Range | –40°C to +125°C | °C |
Key Features
- High-speed SAR ADC with 500 kSPS conversion rate
- Software-programmable bipolar and unipolar input ranges
- On-chip 4.096-V reference with low drift
- Input overvoltage protection up to ±20 V
- High resistive input impedance (≥ 1 MΩ)
- MultiSPI digital interface compatible with traditional SPI protocol
- Extended industrial temperature range: –40°C to +125°C
- Excellent performance metrics: DNL ±0.4 LSB, INL ±0.5 LSB, SNR 90.5 dB, THD –112 dB
Applications
- Analog input modules
- Semiconductor test equipment
- Servo drive control modules
- High-speed data acquisition systems
Q & A
- What is the conversion rate of the ADS8685IPWR?
The ADS8685IPWR operates at a conversion rate of 500 kSPS.
- What are the available input ranges for the ADS8685IPWR?
The device offers both bipolar and unipolar input ranges, including ±12.288 V, ±10.24 V, ±6.144 V, ±5.12 V, ±2.56 V, and 0 V–12.288 V, 0 V–10.24 V, 0 V–6.144 V, 0 V–5.12 V.
- What is the analog supply voltage range for the ADS8685IPWR?
The analog supply voltage range is 4.75–5.25 V.
- Does the ADS8685IPWR have input overvoltage protection?
- What is the operating temperature range of the ADS8685IPWR?
The operating temperature range is –40°C to +125°C.
- What is the signal-to-noise ratio (SNR) of the ADS8685IPWR?
The SNR is 90.5 dB.
- What is the total harmonic distortion (THD) of the ADS8685IPWR?
The THD is –112 dB.
- Does the ADS8685IPWR support SPI-compatible serial interface?
- What are some typical applications of the ADS8685IPWR?
Typical applications include analog input modules, semiconductor test equipment, and servo drive control modules.
- What is the input impedance of the ADS8685IPWR?
The input impedance is ≥ 1 MΩ.
