NXP Semiconductors PXN2020 - 3.4.14 Clock Synthesizer Signals; 3.4.14.1 Crystal Oscillator Input; External Clock Input EXTAL; 3.4.14.2 Crystal Oscillator Output XTAL; 3.4.14.3 System Clock Output CLKOUT

Signal Description
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor 3-41
3.4.14 Clock Synthesizer Signals
3.4.14.1 Crystal Oscillator Input / External Clock Input
EXTAL
EXTAL is the input pin for an external crystal oscillator or an external clock source.
3.4.14.2 Crystal Oscillator Output
XTAL
XTAL is the output pin for an external crystal oscillator.
3.4.14.3 System Clock Output
CLKOUT
CLKOUT is the device system clock output. This signal is multiplexed with PK9 (user mode) and PK0
(test mode).
3.4.15 Power / Ground Signals
3.4.15.1 Internal Logic Supply Input
V
DD
V
DD
is the 1.2 V (nominal) internal logic supply input.
3.4.15.2 Fixed 3.3V Internal Supply Input
V
DD33
V
DD33
is the 3.3V (nominal) internal supply input.
3.4.15.3 Analog Supply
V
DDA
V
DDA
is the 3.3 or 5.0 V (nominal) analog supply input pin for the ADC.
3.4.15.4 External I/O Supply Input
V
DDEn
V
DDEn
is the 3.3 or 5.0 V (nominal) external I/O supply input. Four separate inputs are provided.
3.4.15.5 Media Local Bus Supply Input
V
DDEMLB
V
DDEMLB
is the 2.5 – 3.3 V supply input for the Media Local Bus interface.