TSL2562, TSL2563
LOW-VOLTAGE
LIGHT-TO-DIGITAL CONVERTER
TAOS066N − AUGUST 2010
29
The LUMENOLOGY r Company
r
r
Copyright E 2010, TAOS Inc.
www.taosinc.com
APPLICATION INFORMATION: HARDWARE
Power Supply Decoupling and Application Hardware Circuit
The power supply lines must be decoupled with a 0.1 μF capacitor placed as close to the device package as
possible (Figure 18). The bypass capacitor should have low effective series resistance (ESR) and low effective
series inductance (ESI), such as the common ceramic types, which provide a low impedance path to ground
at high frequencies to handle transient currents caused by internal logic switching.
TSL2562/
TSL2563
V
BUS
V
DD
0.1 F
R
P
R
P
SCL
SDA
R
PI
INT
Figure 18. Bus Pull-Up Resistors
Pull-up resistors (Rp) maintain the SDAH and SCLH lines at a high level when the bus is free and ensure the
signals are pulled up from a low to a high level within the required rise time. For a complete description of the
SMBus maximum and minimum Rp values, please review the SMBus Specification at
http://www.smbus.org/specs. For a complete description of I
2
C maximum and minimum Rp values, please
review the I
2
C Specification at http://www.semiconductors.philips.com.
A pull-up resistor (R
PI
) is also required for the interrupt (INT), which functions as a wired-AND signal in a similar
fashion to the SCL and SDA lines. A typical impedance value between 10 kΩ and 100 kΩ can be used. Please
note that while Figure 18 shows INT being pulled up to V
DD
, the interrupt can optionally be pulled up to V
BUS
.
