MCP3008 IC: Datasheet, Pinout, Specifications

Symbol

Footprint

3D Model

The Microchip Technology Inc. MCP3008 device is a successive approximation of 10-bit analogue-to-digital (A/D) converters with onboard samples and holds circuitry. The MCP3008 is programmable to provide four pseudo-differential input pairs or eight single-ended inputs. The device is capable of conversion rates of up to 200 ksps.

Microchip Technology MCP3008-I/P technical specifications, attributes, parameters and parts with similar specifications to Microchip Technology MCP3008-I/P.

• 10-bit resolution

• ± 1 LSB max DNL

• ± 1 LSB max INL

• 4 (MCP3004) or 8 (MCP3008) input channels

• Analog inputs programmable as single-ended or pseudo-differential pairs

• On-chip sample and hold

• SPI serial interface (modes 0,0 and 1,1)

• Single supply operation: 2.7V - 5.5V

• 200 ksps max. sampling rate at VDD = 5V

• 75 ksps max. sampling rate at VDD = 2.7V

• Low power CMOS technology

• 5 nA typical standby current, 2 µA max.

• 500 µA max. active current at 5V

• Industrial temp range: -40°C to +85°C

• Available in PDIP, SOIC and TSSOP packages

• Sensor Interface

• Process Control

• Data Acquisition

• Battery Operated Systems

The MCP3008 is an 8-Channel 10-bit ADC IC, so it can measure 8 different analogue voltages with a resolution of 10-bit. It measures the value of analogue voltage from 0-1023 and sends the value to a microcontroller or microprocessor through SPI communication. It can operate on both 3.3V and 5V and hence it can be used with a 5V microcontroller as well as with 3.3V systems like the Raspberry Pi. It uses the SAR method to convert the Analog voltage to digital value; it might not be the fastest and precise ADC in the market but is the cheapest and easy to use one.

The MCP3008 is popular because of its user-friendly nature and can be made to work with a minimum number of components. A sample application circuit for MCP3008 is shown below.

In this simple diagram, I have set the operating voltage to be 5V, but it can be anywhere between 2.7V to 5V. The ADC works using the SAR method, so it requires a reference voltage to calculate the unknown voltage. This reference voltage should always be less than the operating voltage; normally it will be as same as the operating voltage. In our case, I have tied the reference voltage to 5V along with Vcc pin.

The channel pin CH0 to CH7 can be used to feed in the analogue voltage which has to be measured. The maximum voltage that can be measured with each is pin will be equal to the reference voltage. In our case it is 5V. Each pin measures the voltage with a resolution of 10-bit meaning the input voltage of 0-5V is converted to 0-1023 digital data. The formulae to convert this digital data back into voltage is:

In the above circuit diagram, the system voltage is 5V and the resolution of ADC is 1024. Once the Analog voltage is measured by the IC, its value can be obtained by the microcontroller or microprocessor through SPI communication. To do this the CS, Din, Dout and Clock pin of the IC is connected to the microcontroller or microprocessors SPI pins. Then using SPI communication protocol we have to send the control bit data for selecting the channel number from which the ADC value has to be obtained and the IC will reply to us back with the value.

Microchip Technology Incorporated is a leading provider of smart, connected and secure embedded control solutions. Its easy-to-use development tools and comprehensive product portfolio enable customers to create optimal designs, which reduce risk while lowering total system cost and time to market.

Download datasheets and manufacturer documentation for Microchip Technology MCP3008-I/P.