LTR-578ALS-WA

6. Functional Block Diagram
LTR-578ALS-01 contains 2 photodiodes (Visible and IR diode) for respective photocurrent measurement. The photodiode
currents are converted to digital values by ADCs. The sensor also included an emitter LED, as well as some peripheral circuits
such as an internal oscillator, a current source, voltage reference, and internal fuses to store trimming information.
Note: It is a must that VDD and VLED to be separated.
I/O Pins Configuration Table
Pin  I/O Type  Symbol  Description
1  IN/OUT  SDA  I 2 C serial data
2  OUT  INT  Interrupt
3  OUT  LDR  Connect to LED Cathode
4  OUT  LEDK  LED Cathode. Connect to LDR pin if internal LED driver circuit is used
5  IN  LEDA  LED Anode.
6  Ground  GND  Ground
7  IN  SCL  I 2 C serial clock
8  Supply  VDD  Power Supply Voltage
Recommended Application Circuit Components
Component  Recommended Value
Rp1, Rp2, Rp3 [1]  1 k? to 10 k?
C1, C3
1uF ?20%, X7R / X5R Ceramic
C2 0.1uF