VCNL4040

www.vishay.com

Vishay Semiconductors

Rev. 1.7, 04-Nov-2020

7

Document Number: 84274

For technical questions, contact: sensorstechsupport@vishay.com

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000

Fig. 10 - IRED Profile

APPLICATION INFORMATION

Pin Connection with the Host

VCNL4040 integrates proximity sensor, ambient light Sensor, and IRED all together with I2C interface. It is very easy for the

baseband (CPU) to access PS and ALS output data via I2C interface without extra software algorithms. The hardware schematic

is shown in the following diagram.

Two additional capacitors in the circuit can be used for the following purposes: (1) the 0.1 μF capacitor near the VDD pin is used

for power supply noise rejection, (2) the 2.2 μF capacitor - connected to the anode - is used to prevent the IRED voltage from

instantly dropping when the IRED is turned on, and (3) 2.2 k

Ω is suitable for the pull up resistor of I2C except for the 8.2 kΩ

applied on the INT pin.

Note

• Cathode (LED) and cathode (sensor): pins need to be connected together externally

Fig. 11 - Hardware Pin Connection Diagram

10

100

1000

10000

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

-90

-60

-30

0

30

60

90

Axis Title

2nd line

Angle (deg)

0°

20°

40°

60°

80°

0.6

0.7

0.8

0.9

1.0

0

0.1

0.2

0.3

0.4

0.5

INT

INT

SCLK

8

7

3

5

1

0.1 μF

GND

SDAT

SCK

SDA

6

2.2 k

Ω

2.2 k

Ω

V

DD_LED

2.2 μF

8.2 k

Ω

2

Cathode

(LED)

Anode

4

VCNL4040

Cathode

(sensor)

V

DD

V

Pull_up

Baseband