Datasheet

C1-
C2+
C2-
C1+
DM1
DM5
DS2
DS1
DM3DM 4 DM2GND
SDATSCLKVIN
C1
C2
1mF
C3
1mF
MainDisplay
C4
SubDisplay
I
2
CInterface
On/Off, DigitalDimming
VOUT
AuxiliaryPortforKeyPad
orFlashLight
4.7 Fm
4.7 Fm
LAYOUT GUIDELINES
TPS60250
TPS60252
www.ti.com ............................................................................................................................................................ SLVS769C – APRIL 2007 – REVISED APRIL 2008
Figure 21. The Typical Application Circuit for Sub, Main, and Keypad Backlight
Figure 21 shows the typical application circuit for sub, main, and keypad backlight. In this application, DM5 is
assigned as the auxiliary input for the keypad lighting application.
There are several points to consider when laying out a PCB for charge pump based solutions. In general, all
capacitors should be as close as possible to the device. This is especially important when placing the flying
capacitors (C2, C3 in Figure 20 and Figure 21 ). In cases where DM5 is assigned for torch/flash applications, with
a maximum 80 mA WLED current, this current path must be kept wide to reduce the trace resistance.
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