CAT4016W-T1 Datasheet, PDF (8/15 Pages) ON Semiconductor – 16-Channel Constant Current LED Driver

CAT4016
PIN DESCRIPTION
Name
GND
SIN
Function
Ground
Serial data input pin
CLK
Serial clock input pin
LATCH
LED1-LED16
Latch serial data to output registers
LED channel 1 to 16 cathode terminals
BLANK
Enable / disable all channels
SOUT
RSET
Serial data output pin.
LED current set pin
VDD
Positive supply Voltage
TAB (TQFN
package only)
Connect to GND on the PCB
PIN FUNCTION
GND is the ground reference pin for the device. This
pin must be connected to the ground plane on the
PCB.
SIN is the serial data input. Data is loaded into the
internal register on each rising edge of CLK.
CLK is the serial clock input. On each rising CLK
edge, data is transferred from SIN to the internal 16-
bit serial shift register.
LATCH is the latch data input. On the rising edge of
LATCH, data is loaded from the 16-bit serial shift
register into the output register latch. On the falling
edge, this data is latched in the output register and
isolated from the state of the serial shift register.
LED1 - LED16 are the LED current sink channels.
These pins are connected to the LED cathodes. The
current sinks drive the LEDs with a current equal to 50
times RSET pin current. For the LED sink to operate
correctly, the voltage on the LED pin must be above
0.4V.
BLANK is the LED channel enable and disable input
pin. When low, LEDs are enabled according to the
output latch register content. When high, all LEDs are
off, while preserving the data in the output latch
register.
SOUT is the serial data output of the 16-bit serial shift
register. This pin is used to cascade several devices
on the serial bus. The SOUT pin is then connected to
the SIN input of the next device on the serial bus to
cascade.
RSET is the LED current setting pin. A resistor is
connected between this pin and ground. Each LED
channel current is set to 50 times the current pulled
out of the pin. The RSET pin voltage is regulated to
1.2V.
VDD is the positive supply pin voltage for the entire
device. A small 1µF ceramic is recommended close
to pin.
Doc. No. MD-5028 Rev. D
8
© 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice.