Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Building ADC for Raspberry Pi

Raspberry Pi lacks ADC functionality that is really necessary when building real world applications. The standard way-out of this situation is to attach external ADC chip that talks to RasPi via SPI or I2C interface. But if you need something that is closer to native peripheral, then take a look at Hussam solution where he builds ADC with comparator circuit. This solution isn’t something new and was used in recent microcontroller circuits where ADC were needed. Anyway this circuit is useful in many ways – first of all it performs ADC. Second is more educational – it simply reminds (or teaches) how ADC work. Functionality of the circuit is rather simple – it utilized two Raspberry Pi pins where one generates PWM and along with RC filter it gives some… Continue reading