An ESP32 and VEML7700 lux sensor example using the Arduino IDE

In this article we look at the VEML7700  which is an ambient light digital 16-bit resolution sensor – we will take a look at some of the technical info on the sensor, show you the layout and a code example using the Arduino IDE

This is the sensor that I bought for this example

Lets look at some information regarding the sensor from the manufacturer

The VEML7700 is a high accuracy ambient light digital 16-bit resolution sensor. It includes a high sensitive photo diode, a low noise amplifier, a 16-bit A/D converter and supports an easy to use I2C bus communication interface.
The ambient light result is as digital value available

FEATURES

Integrated modules: ambient light sensor (ALS)
Supply voltage range VDD: 2.5 V to 3.6 V
Communication via I2C interface
Floor life: 72 h, MSL 4, according to J-STD-020
Low shut down current consumption: typ. 0.5 μA

AMBIENT LIGHT FUNCTION

Filtron TM technology adaption: close to real human eye response
O-Trim TM technology adoption: ALS output tolerance≤ 10 %
16-bit dynamic range for ambient light detection from 0 lx to about 120 klx with resolution down to 0.0036 lx/ct,supports low transmittance (dark) lens design
100 Hz and 120 Hz flicker noise rejection
Excellent temperature compensation
High dynamic detection resolution
Software shutdown mode control

Parts Required

Here are the parts required

Name	Link
ESP32		Aliexpress link Amazon Ebay
VEML7700		Aliexpress link Ebay link Amazon Link
Connecting cables		Aliexpress link Amazon Ebay

Schematic/Connection

This is an easy sensor to connect – simply connect SDA and SCL from the ESP32 board and then connect the power pins.

You can see this in the layout below.

esp32 and veml7700 layout

Code Example

This uses the library from https://github.com/DFRobot/DFRobot_VEML7700

I tried an Adafruit one – could not get the library to work, various errors. The one above worked out of the box

[codesyntax lang=”cpp”]

#include <Wire.h>
#include "DFRobot_VEML7700.h"

DFRobot_VEML7700 als;

void setup()
{
  Serial.begin(9600);
  als.begin();
}

void loop()
{
  float lux;
  
  als.getALSLux(lux);
  Serial.print("Lux:");
  Serial.print(lux);
  Serial.println(" lx");
  
  delay(200);
}

[/codesyntax]

Output

Open the serial monitor and you should see something like this, shine light, cover the sensor to change the lux values

Lux:108.22 lx
Lux:177.54 lx
Lux:192.98 lx
Lux:203.96 lx
Lux:62.78 lx
Lux:25.92 lx
Lux:20.70 lx
Lux:19.08 lx
Lux:18.68 lx
Lux:20.24 lx
Lux:19.57 lx
Lux:20.21 lx
Lux:37.35 lx
Lux:44.85 lx

Links

https://www.vishay.com/docs/84286/veml7700.pdf