EVAL-ADUC7060QSPZ Analog Devices Inc, EVAL-ADUC7060QSPZ Datasheet - Page 49

• Manufacturer Part Number: EVAL-ADUC7060QSPZ
• Description: Quick Start Development System
• Manufacturer: Analog Devices Inc
• Series: QuickStart™ PLUS Kitr
• Type: MCU, ARM7r

Specifications of EVAL-ADUC7060QSPZ

• Contents: Evaluation Board, Power Supply, Cable, Software, Emulator and Documentation
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: ADuC7060
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: Q5189809

Excitation Current Sources Control Register
Name:
Address:
Default value:
Access:
Function:
Table 60. IEXCON MMR Bit Designations
Bits
7
6
5
4
3:1
0
EXAMPLE APPLICATION CIRCUITS
Figure 17 shows a simple bridge sensor interface to the ADuC7060,
including the RC filters on the analog input channels. Notice
that the sense lines from the bridge (connecting to the reference
inputs) are wired separately from the excitation lines (going to
DVDD/AVDD and ground). This results in a total of six wires
going to the bridge. This 6-wire connection scheme is a feature
of most off-the-shelf bridge transducers (such as load cells) that
helps to minimize errors that would otherwise result from wire
impedances.
Name
IEXC1_EN
IEXC0_EN
IEXC1_DIR
IEXC0_DIR
IOUT[3:1]
IOUT[0]
IEXCON
0xFFFF0570
0x00
Read and write
This 8-bit MMR controls the two excitation current sources, IEXC0 and IEXC1.
These bits control the excitation current level for each source.
Set this bit = 1 to enable 10 μA diagnostic current source.
Description
Enable bit for IEXC1 current source.
Set this bit = 1 to enable Excitation Current Source 1.
Clear this bit to disable Excitation Current Source 1.
Enable bit for IEXC0 current source.
Set this bit = 1 to enable Excitation Current Source 0.
Clear this bit to disable Excitation Current Source 0.
Set this bit = 1 to direct Excitation Current Source 1 to the IEXC0 pin.
Set this bit = 0 to direct Excitation Current Source 1 to the IEXC1 pin.
Set this bit = 1 to direct Excitation Current Source 0 to the IEXC1 pin.
Set this bit = 0 to direct Excitation Current Source 0 to the IEXC0 pin.
IOUT[3:1] = 000, excitation current = 0 μA + (IOUT[0] × 10 μA).
IOUT[3:1] = 001, excitation current = 200 μA + (IOUT[0] × 10 μA).
IOUT[3:1] = 010, excitation current = 400 μA+ (IOUT[0] × 10 μA).
IOUT[3:1] = 011, excitation current = 600 μA+ (IOUT[0] × 10 μA).
IOUT[3:1] = 100, excitation current = 800 μA+ (IOUT[0] × 10 μA).
IOUT[3:1] = 101, excitation current = 1 mA + (IOUT[0] × 10 μA).
All other values are undefined.
Clear this bit = 0 to disable 10 μA diagnostic current source.
Rev. 0 | Page 49 of 100
In Figure 18, AD592 is an external temperature sensor used to
measure the thermocouple cold junction, and its output is con-
nected to the auxiliary channel. ADR280 is an external 1.2 V
reference part—alternatively, the internal reference can be used.
Here, the thermocouple is connected to the primary ADC as
a differential input to ADC0/ADC1. Note the resistor between
VREF+ and ADC1 to bias the ADC inputs above 100 mV.
Figure 19 shows a simple 4-wire RTD interface circuit. As with
the bridge transducer implementation in Figure 17, if a power
supply and a serial connection to the outside world are added,
then Figure 19 represents a complete system.
ADuC7060