Evaluation Board Features - Analog Devices MICROCONVERTER ADUC7024 Reference Manual

ADuC7024 Evaluation Board Reference Guide

(2) Evaluation Board Features

(2) E B F
VALUATION OARD EATURES
Power Supply:
The user should connect the 9V power supply via the 2.1mm input power socket (J5). The input
connector is configured as 'CENTER NEGATIVE' i.e. GND on the center pin and +9V on the outer
shield.
This 9V supply is regulated via a linear voltage regulator (U5). The 3.3V regulator output is used to drive
the digital side of the board directly. The 3.3V supply is also filtered and then used to supply the analog
side of the board.
When on, the LED (D3) indicates that a valid 3.3V supply is being driven from the regulator circuit. All
active components are decoupled with 0.1uF at device supply pins to ground.
RS232 Interface:
The ADuC7024 (U1) P1.1 and P1.0 lines are connected to the RS232 Interface Cable via connector (J1).
The Interface Cable generates the required level shifting to allow direct connection to a PC serial port.
Ensure that the cable supplied is connected to the board correctly i.e. DVDD is connected to DVDD and
DGND is connected to DGND.
Emulation Interface:
Non-intrusive emulation and download are possible on the ADuC7024 via JTAG by connecting a JTAG
emulator to the J4 connector.
Crystal Circuit:
The board is fitted with a 32.768kHz crystal, from which the on-chip PLL circuit can generate a
41.78MHz clock.
External Reference (ADR291)
The external 2.5V reference chip (U2) has two functions. It is provided on the evaluation board to
demonstrate the external reference option of the ADuC7024 but its main purpose is to generate the V
OCM
voltage of the differential amplifier if required.
Reset/Download/IRQ0 Push Buttons:
A RESET push button is provided to allow the user to manually reset the part. When inserted the RESET
pin of the ADuC7024 will be pulled to DGND. Because the RESET pin on the ADuC7024 is Schmidt
triggered internally there is no need to use an external Schmidt trigger on this pin.
When inserted the IRQ0 push button switch drives P0.4/IRQ0 high. This can be used to initiate an
external interrupt 0.
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Rev. 1.0 Analog Devices Inc., MicroConverter
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