Datasheet

ADuC7033
Rev. B | Page 18 of 140
Pin No. Mnemonic Type
1
Description
31 GPIO_4/ECLK I/O
General-Purpose Digital Input/Output 4, Clock. This is a multifunction pin. By default and after
power-on reset, this pin is configured as an input. The pin has an internal weak pull-up resistor.
This pin remains unconnected when not in use. This multifunction pin can be configured in
one of two states, namely
General-Purpose Digital I/O 4.
Output a 2.56 MHz clock.
33 REG_DVDD S Nominal 2.6 V Output from On-Chip Regulator.
36 XTAL1 O Crystal Oscillator Output. If an external crystal is not used, this pin is left unconnected.
37 XTAL2 I
Crystal Oscillator Input. If an external crystal is not used, connect this pin to the DGND system
ground.
41 WU I/O
High Voltage Wake-Up Pin. This high voltage I/O pin has an internal 10 kΩ pull-down resistor
and a high-side driver to VDD. If this pin is not used, do not externally connect it.
42 VDD S Battery Power Supply to On-Chip Regulator.
44 VSS S Ground Reference. This is the ground reference for the internal voltage regulators.
46 STI I/O
High Voltage Serial Test Interface Output Pin. If this pin is not used, externally connect it to the
IO_VSS ground reference.
47 IO_VSS S Ground Reference for High Voltage I/O Pins.
48 LIN/BSD I/O LIN Serial Interface Input/Output Pin. This is a high voltage pin.
1
I = input, O = output, S = supply.