Overview

3-pin JST PH-style cable connected to a Sharp analog distance sensor.

The Sharp distance sensors are a popular choice for many projects that require accurate distance measurements. This IR sensor is more economical than sonar rangefinders, yet it provides much better performance than other IR alternatives. Interfacing to most microcontrollers is straightforward: the single analog output can be connected to an analog-to-digital converter for taking distance measurements, or the output can be connected to a comparator for threshold detection. The detection range of this version is approximately 20 cm to 150 cm (8″ to 60″).

The GP2Y0A02 uses a 3-pin JST PH connector that works with our 3-pin JST PH cables for Sharp distance sensors (not included); the top picture on the right shows a shorter-range Sharp analog distance sensor with one of these cables. These cables have 3-pin JST connectors on one end and are available with pre-crimped male pins, pre-crimped female pins, and with unterminated wires on the other end. It is also possible to solder three wires to the sensor where the connector pins are mounted (see the lower picture to the right). When looking at the back, the three connections from left to right are power, ground, and the output signal.

We also carry an assortment of mounting brackets designed specifically for this sensor. The pictures below show these brackets being used with a shorter-range version of this sensor, which has the same width and height but a shorter depth:

Family of brackets for Sharp GP2Y0A02, GP2Y0A21, and GP2Y0A41 Distance Sensors.

Feature summary

Linearizing the output

The relationship between the sensor’s output voltage and the inverse of the measured distance is approximately linear over the sensor’s usable range. The GP2Y0A02YK datasheet (703k pdf) contains a plot of analog output voltage as a function of the inverse of distance to a reflective object. You can use this plot to convert the sensor output voltage to an approximate distance by constructing a best-fit line that relates the inverse of the output voltage (V) to distance (cm).

Alternative Sharp distance sensors

We have a variety of Sharp distance sensors to choose from. The closest alternative to this GP2Y0A02YK0F module is the newer Sharp GP2Y0A60SZ analog distance sensor (10 – 150 cm), which has the same maximum sensing distance but offers a lower minimum detection distance and more than twice the sampling rate in a much smaller package:

Sharp GP2Y0A02YK0F Sensor 20-150cm (left) next to Pololu Carrier with Sharp GP2Y0A60SZLF Sensor 10-150cm (right).

We also carry two shorter-range versions of this sensor: the Sharp GP2Y0A41SK0F analog distance sensor (4 – 30 cm) and the Sharp GP2Y0A21YK0F analog distance sensor (10 – 80 cm). These two analog distance sensors have identical packages and pin-outs, making it easy to swap one version for another should your application requirements change, and they have the same mounting hole locations and cable connector as this GP2Y0A02YK0F.

For very short-range detection applications, we carry a 2-15 cm analog Sharp distance sensor. We also carry three digital Sharp distance sensors that have low minimum detection distances and a high 400 Hz update rate. They are available with a 5 cm, 10 cm, or 15 cm range and simply tell you if something is in their detection range, not how far away it is. They are smaller than the analog Sharp distance sensors and draw less current.

A variety of Sharp distance sensors. From left to right: GP2Y0A02, GP2Y0A21 or GP2Y0A41, GP2Y0A51, and GP2Y0D8xx.