Microchip Technology ATtiny3217 Xplained Pro, Руководство пользователя

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• Reference clock : Reference clock for the XAM.
3.2.3 Sample Rate
The raw sampling rate of the XAM is up to 250 kHz, and with the default averaging configuration (average of 16
samples), the actual output of the XAM is 16.67 ksps.
Info: The XAM output sample rate is not an integer fraction of the raw sampling.
3.2.4 Measurement Ranges and Accuracy
The XAM has four measurement ranges. These are defined by two shunt resistors and two gain stages.
Table 3-2. XAM Measurement Ranges and Accuracy
Measurement
Range Hardware Resolution Accuracy Comments
Range 1 Low current shunt and high
gain stage 20 nA 1 LSB ±1% Accuracy will decrease below 1
μA. The typical accuracy for 300
nA is 1 LSB ±10%.
Range 2 Low current shunt and low
gain stage 150 nA 1 LSB ±1%
Range 3 High current shunt and high
gain stage 10 μA 1 LSB ±1%
Range 4 High current shunt and low
gain stage 100 μA 1 LSB ±1% Accuracy will decrease above 100
mA. Typical accuracy is 1 LSB
±5% at 400 mA. The maximum
current is 400 mA.
The ranges are automatically switched by the XAM to achieve the best measurement results, and the currently active
range is visualized in the
Data Visualizer front-end tool. The maximum voltage drop over the shunt resistor is 100 mV,
and the XAM switches the range automatically before reaching this limit.
3.3 Hardware Identification System
All Xplained Pro extension boards come with an identification chip (ATSHA204A CryptoAuthentication
™
chip) to
uniquely identify the boards that are connected to the Xplained Pro Evaluation Kit. This chip contains information that
identifies the extension with its name and some extra data. When an Xplained Pro extension is connected to an
Xplained Pro Evaluation Kit, the information is read and sent to the Atmel Studio/MPLAB
®
X. The following table
shows the data fields stored in the ID chip with example content.
Table 3-3. Xplained Pro ID Chip Content
Data Field Data Type Example Content
Manufacturer ASCII string Microchip'\0'
Product name ASCII string Segment LCD1 Xplained Pro'\0'
Product revision ASCII string 02'\0'
Product serial number ASCII string 1774020200000010’\0’
Minimum voltage [mV] uint16_t 3000
ATtiny3217 Xplained Pro
Xplained Pro
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2020 Microchip Technology Inc.
User Guide
DS50002765B-page 9