CAT3606 Datasheet, PDF (9/11 Pages) Catalyst Semiconductor – 6-Channel Low Noise Charge Pump White LED Driver

CAT3606
TYPICAL CHARACTERISTICS
VIN = 3.6V, EN = VIN, ENM = ENS = GND, C_IN = C_OUT = 1µF, T_AMB = 25˚C, unless otherwise specified.
Foldback Current Limiting
5
4
1x mode
3
2
1
RSET Pin Voltage vs. Temperature
1.24
1.22
1.20
1.18
0
0 100 200 300 400 500
OUTPUT CURRENT [mA]
PWM Dimming at 1kHz on ENM and ENS
1.16
-50 -25 0
25 50 75 100 125
TEMPERATURE [°C]
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.
© 2005 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
9
Figure 2: PCB Layout
Doc. No. 5009, Rev. B