Samsung S5PC100 User Manual page 616

S5PC100 USER'S MANUAL (REV1.0)
9 32.768KHZ X-TAL CONNECTION EXAMPLE
The Figure 7.4-2 shows a circuit of the RTC unit oscillation at 32.768kHz.
Note. The external components commonly used for the above circuit are a resonator, two capacitors(15~22 pF)
and a resistor(>5MΩ) between XrtcXTI and XrtcXTO.
10 DRIVE STRENGTH CONTROL
For more information, refer to ETC4DRV(0xE030_056C) in Pad Control.doc
SFR Name
ETC4DRV
11 RTC START
To start RTC, set RTCCON[0] as 1.
12 I/O DESCRIPTION
Function Signal
RTC_XTI
RTC_XXTO
NOTE: Type field indicates whether pads are dedicated to the signal or pads are connected to the multiplexed signals.
15~ 22pF
Figure 7.4-2 Main Oscillator Circuit Example
Field Value
1
0(default)
I/O
Input 32.768 KHz RTC Oscillator Clock Input
Output 32.768 KHz RTC Oscillator Clock output
XrtcXTI
32768 Hz
XrtcXTO
Min Type
1.7 1.8
2.3 2.5~3.3
Description
REAL TIME CLOCK
Max Unit
1.9 V
3.6 V
Pad Type
XrtcXTI Dedicated
XrtcXTO Dedicated
7.4-5