Datasheet

CAT3637
http://onsemi.com
9
Table 5. PIN DESCRIPTION
Pin # Name Function
1 LED6 LED6 cathode terminal
2 LED5 LED5 cathode terminal
3 LED4 LED4 cathode terminal
4 LED3 LED3 cathode terminal
5 LED2 LED2 cathode terminal
6 LED1 LED1 cathode terminal
7 VOUT Charge pump output, connect to LED anodes
8 VIN Charge pump input, connect to battery or supply
9 C1+ Bucket capacitor 1, positive terminal
10 C1− Bucket capacitor 1, negative terminal
11 C2+ Bucket capacitor 2, positive terminal
12 C2− Bucket capacitor 2, negative terminal
13/14 NC No connect
15 GND Ground reference
16 EN/SET Device enable (active high) and 1 wire control input
TAB TAB Connect to GND on the PCB
Pin Function
VIN is the supply pin for the charge pump. A small 1 mF
ceramic bypass capacitor is required between the VIN pin
and ground near the device. The operating input voltage
range is from 2.5 V to 5.5 V. Whenever the input supply falls
below the under−voltage threshold (2 V) all the LED
channels will be automatically disabled and the device
register are reset to default values.
EN/SET is the enable and one wire addressable control logic
input for all LED channels. Guaranteed levels of logic high
and logic low are set at 1.3 V and 0.4 V respectively. When
EN/SET is initially taken high, the device becomes enabled
and all LED currents remain at 0 mA. To place the device
into zero current mode, the EN/SET pin must be held low for
more than 1.5 ms.
VOUT is the charge pump output that is connected to the
LED anodes. A small 1 mF ceramic bypass capacitor is
required between the VOUT pin and ground near the device.
GND is the ground reference for the charge pump. The pin
must be connected to the ground plane on the PCB.
C1+, C1− are connected to each side of the ceramic bucket
capacitor C1.
C2+, C2− are connected to each side of the ceramic bucket
capacitor C2.
LED1 to LED6 provide the internal regulated current for
each of the LED cathodes. These pins enter high−impedance
zero current state whenever the device is placed in shutdown
mode.
TAB is the exposed pad underneath the package. For best
thermal performance, the tab should be soldered to the PCB
and connected to the ground plane.