ra8803 RAIO Technology Inc., ra8803 Datasheet - Page 30

• Manufacturer Part Number: ra8803
• Description: Two Layers Character/graphic Lcd Controller Specification
• Manufacturer: RAIO Technology Inc.

Version 2.5
RAiO
6-8 DAC
6-9 ADC
TECHNOLOGY INC.
6-7-2 External Clock
The RA8803/8822 built-in one 5-bit fixed current type Digital-to-Analog Converter (D/A). This DAC will
generate different current output through the setting of register. So users can use it to control the
external booster and adjust the LCD voltage to control the brightness of LCD panel. The DAC out put
“IOUT” is tri-state when DAC disable.
The RA8803/8822 built in a 10-Bit ADC and some control circuits to easily interface to 4-wries analog
resistive touch screens. The users only need to connect the touch panel signals -- XL, XR, YU, and YD
to RA8803/8822. The RA8803/8822 will continuous to monitor the screen and waiting for a touch. When
the screen was being touched, the RA8803/8822 will performs analog to digital conversion to determine
the location of the touch, stores the X and Y locations in the registers, and can issues an interrupt for
MPU.
Figure 6-4 is the PLL & OSC application circuit.
RA8803/8822 can accept external CLK for system clock source. Directly connecting to XA, and
keep XB, LPF floating.
0.022µ
2.4KΩ
Clock Use X’tal/PLL Mode: SYS_FQ Pull-Low
Figure 6-4: PLL Application Circuit
0.22 µ
20P
20P
30/48
32768Hz
Two Layers Character/Graphical LCD Controller
XA
XB
LPF
RA8803
RA8803/8822
www.raio.com.tw