E981.03 Datasheet, PDF (18/51 Pages) ELMOS Semiconductor AG – Autonomous MAC and individual physical address

KNX/ EIB TRANSCEIVER
PRODUCTION DATA - JAN 15, 2015
E981.03
f_XTAL,sync
e.g. from host
processor
CLK source
E981.03
XTAL _Q1
XTAL
EXTAL
crystal
CXTAL
CEXTAL
OSC_Q
1
divider
D_Q
0
OSC_RC
sync
PLL
CLKin
CLKUART
CLKSPI
CLKKNX
CLKMemory
ACLK
Figure 7. Clock Generation
5.9 Clock System
The main clock is generated by an internal RC oscilla-
tor. An external clock reference / crystal can be used to
achieve a system clock accuracy of approx 0.05%.
Two different synchronization clocks are useable:
The sync - signal source could be a crystal oscilla-
tor (OSCQ) or an external VIO related digital clock on
XTAL(remark: absolute maximum rating “V”). The IC au-
tomatically detects the used mode and selects the cor-
rect internal signal path.
1) Crystal at f_Q = 7.3728 MHz
• default configuration
• foot point capacitors are incl
In Analog Mode no crystal and no external clock are re-
quired. To increase the robustness to EMI the input XTAL
shall be connected to GND if not used.
2) Clock reference at f = _XTAL,sync 126.562 Hz
• the crystal oscillator should be switched off
- EXT_Q to 1 in CLK_CTRL Register
6 Mode Depending Device Functions
V_33I not ok
Hard
reset
V_33I ok
Soft
start
Reset
condition
Soft start
finished
Save
Voltage
VST
not ok
Voltage
VST ok
Communication
Mode
Met alarm
condition
Receive Trigger
Telegram
End of alarm
telegram transmition
No condition
Trigger
1)
Alarm
2)
Figure 8. Device Modes
1) Trigger mode only available from Normal Mode
2) Alarm mode not available in Analog Mode see chapter 6.5 Analog Mode
Elmos Semiconductor AG reserves the right to change the detail specifications as may be required to permit improvements in the design of its products.
Elmos Semiconductor AG
Data Sheet
QM-No.: 25DS0046E.03
18/51