3PEAK – TPC6240 Sigma-Delta ADC: 3PEAK is headquartered in Suzhou, China and Plano, Texas, USA. Europe is served by a dedicated team from Munich (Germany).
The development and supply of ICs for the complete signal chain is one of 3PEAK’s priorities. In addition to operational amplifiers, voltage references and other components, this also includes analog-to-digital converters (ADCs).
3PEAK offers a range of high-precision ADCs. The latest device in this range is a highly integrated 24-bit sigma-delta ADC with 8/16 channels – the TPC6240. In addition to an integrated PGA, voltage reference and digital filters, the TPC6240 has some interesting features for external (resistive) sensors such as RTDs, thermistors and thermocouples. These include adjustable current sources (for sensor excitation current and burn-out detection) and the option of generating a sensor bias voltage.
This makes the ADC ideal for various applications requiring precise measurement of analog signals with a low bandwidth. For example, in process monitoring or temperature and pressure measurement.
The TPC6240 offers 8 differential or 16 single-ended inputs. In addition, there is a low noise PGA to amplify weak signals with a gain of up to 128. The PGA can also be bypassed if required.
In addition to the amplification of the PGA, the selected sampling rate significantly determines the noise performance and the effective resolution of the ADC. The sampling rate can be set between 2.5sps and 8ksps. Depending on the setting, an effective resolution of 24bit or a noise-free resolution of 22bit can be achieved.
An internal voltage reference of 2.5V is available in the ADC. It has an accuracy of ±0.1% at a temperature drift of 20ppm/°C.
For other or more precise reference values, inputs for two external voltage references are available, which can also be found in the 3PEAK portfolio.
The TPC6240 can be operated with its integrated 4MHz oscillator (accuracy of ±2%) or an external clock source.
To optimize the noise performance, the TPC6240 includes digital filters. The FIR low-latency filter (LLF) is very useful if several channels need to be sampled in the shortest possible time. If latency is not a priority, a SincN filter enables significantly improved noise performance. Both filters also provide 50Hz and 60Hz noise rejection.
Despite the integrated PGA has a very low offset drift, it is possible that a small offset drift remains. To further reduce this offset and its drift, the TPC6240 offers a so-called “Global Chop Mode”. If activated, the ADC performs two sequential conversions with reversed polarity, eliminating the offset.
As briefly mentioned above, the TPC6240 contains two matched current sources that can provide an excitation current between 10µA and 2mA for external resistive sensors via the input multiplexer. This helps to reduce system complexity.
An adjustable bias voltage generator with two voltage levels is also available. This can be used, for example, for thermocouples that require a bias voltage.
The TPC6240 additionally integrates calibration functions for offset and gain. This calibration can also be performed automatically in “Calibration Mode”.
Several additional system monitoring functions are integrated in the TPC6240, which are measured via the multiplexer:
All details on the TPC6240 can be found in the data sheet referenced above. We would be happy to advise you on component selection for your next design with ADC. Get in contact with us directly or send us your inquiry here