Posts tagged ‘AD/DA’

Extending DAC Resolution Using Digital Potentiometer

One way to extend the resolution of a digital-to-analog converter (DAC) is by employing a sigma-delta converter in software. The main disadvantage of such approach is the slow speed. Alternatively, we can use some extra hardware to extend the usable resolution of a DAC. In this post, I will illustrate one such method to extend an 8-bit DAC to 16 bits using a digital potentiometer. Continue reading ‘Extending DAC Resolution Using Digital Potentiometer’ »

Interfacing ADS1224 With Arduino

ADS1224 is a 24-bit delta-sigma analog-to-digital converter with 4-channel differential inputs multiplexer. This ADC chip offers a 20-bit effective resolution (6 to 7 digits of resolution in full scale), which makes it ideal in high-resolution voltage measurement applications. Continue reading ‘Interfacing ADS1224 With Arduino’ »

Arduino Library For MCP342X

Last time, I discussed how to interface TI’s ADS1112 16-bit delta-sigma A/D converter with Arduino. Today I am going to introduce you to a set of easy-to-program A/D chips from Microchip. MCP3246/7/8 are a family of 16-bit Delta-Sigma A/D converters with an I2C interface. MCP3426 and MCP3427 both have two differential input channels, while MCP3429 has four differential input channels. The programming for all three devices are essentially the same, except for the number of available channels. Continue reading ‘Arduino Library For MCP342X’ »

Interfacing ADS1112 With Arduino

ADS1112 is a 16-bit delta-sigma A/D converter. This A/D chip has an I2C interface, a 2.048V internal voltage reference and performs a self-calibration on each conversion. These characteristics make it very easy to work with an MCU such as ATmega328p. Continue reading ‘Interfacing ADS1112 With Arduino’ »

AD7705/AD7706 Library Revisited

About a year ago, I wrote a simple library for interfacing AD7705/AD7706 with Arduino. The library works, but it requires some decent knowledge of the underlying chip, which had made it somewhat difficult to use. Most issues users reported can be resolved by adjusting the timing in user code, but I admit that it is somewhat difficult for users who are not familiar with the chip. For a library, I should have made it easier to use to begin with. So, I decided to add a few long-awaited features and hopefully these tweaks will make the library easier to use. Continue reading ‘AD7705/AD7706 Library Revisited’ »

AD7705/AD7706 Library

AD7705 and AD7706 are two 16-bit Sigma Delta ADCs. Equipped with on-chip digital filters and programmable gain front ends, these chips are ideal for low frequency multi-channel signal measurements. The main difference between AD7705 and AD7706 is that AD7705 has two fully differential input channels while AD7706 has three pseudo differential input channels. Continue reading ‘AD7705/AD7706 Library’ »

A Library for LTC1665/LTC1660

ATmega328p does not provide any Digital/Analog conversion channels (although the D/A conversion can be simulated by means of measuring the PWM output). We can easily add up to eight D/A channels using either a LTC1665 (8 bit) or LTC1660 (10 bit) from Linear Technology. Continue reading ‘A Library for LTC1665/LTC1660’ »