CAT3606HV4-T2 Datasheet, PDF (9/12 Pages) ON Semiconductor – 6-Channel Low Noise Charge Pump White LED Driver

CAT3606
TYPICAL CHARACTERISTICS
VIN = 3.6V, EN = VIN, E¯N¯M¯ = E¯N¯¯S = GND, C_IN = C_OUT = 1µF, T_AMB = 25ºC, unless otherwise specified.
Foldback Current Limiting
5
RSET Pin Voltage vs. Temperature
1.24
4
1x mode
3
2
1
1.22
1.20
1.18
0
0
100 200 300 400 500
OUTPUT CURRENT [mA]
1.16
-50 -25
0
25 50 75 100 125
TEMPERATURE [ºC]
PWM Dimming at 1kHz on ENM and ENS
RECOMMENDED LAYOUT
When the driver is in the 1.5x charge pump mode, the
1MHz switching frequency operation requires to
minimize trace length and impedance to ground on all 4
capacitors. A ground plane should cover the area on
the bottom side of the PCB opposite to the IC and the
bypass capacitors. Capacitors Cin and Cout require
short connection to ground which can be done with
multiple vias as shown on Figure 2. A square copper
area matches the QFN16 exposed pad (GND) and
must be connected to the ground plane underneath.
The use of multiple via will improve the heat dissipation.
© 2008 SCILLC. All rights reserved.
9
Characteristics subject to change without notice
Figure 2. PCB Layout
Doc. No. MD-5009 Rev. D