BECKHOFF ET1200 - Manual (Page 56)

Example Schematics
III-46 Slave Controller – ET1200 Hardware Description
25 MHz
OSC_OUT
OSC_IN
ET1200 Ethernet
PHY
CLK25
Figure 25: Oscillator clock source for ET1200 and Ethernet PHYs
9.2 Power supply
Optional external
V
CC I/O
supply
(e.g., V
CC I/O Ext
= Vcc)
Optional external core
supply
ET1200
V
CC_PLL
V
CC Core
V
CC I/O
V
CC I/O Ext
GND
PLL
GND
Core
GND
I/O
GND
PLL
GND
Core
GND
I/O
LDO
Vcc Core
V
CC Core Ext
V
CC
V
CC
GND
LDO
Vcc I/O
GND
GND
Core
220pF 100 nF 10µF
220pF 100 nF 10µF
220pF 100 nF 10µF
220pF 100 nF
Figure 26: ET1200 power supply
Recommendation for voltage stabilization capacitors: 220pF and 100nF ceramic capacitors for each power pin
pair, additional 10µF tantalum electrolytic capacitor for V
CC
, V
CC I/O
, and V
CC Core
/V
CC PLL
, i.e., a total of three 10µF
capacitors.
GND, GND
I/O
, GND
Core
, and GND
PLL
can be connected to a single GND potential.
The internal LDOs are self-deactivating if the actual V
CCI/O
or VCC
Core
/V
CC PLL
voltage is higher than the
respective nominal LDO output voltage.