Analog Devices │
8
MAX22005PMB#
Evaluates: MAX22005
The analog input pin numbering in this document and
their corresponding J2 and J3 analog input connector and
IC pin names are summarized in
The Munich GUI provides an intuitive way to easily ana
-
lyze four single-ended “universal” analog inputs, i.e.,
an input that can measure Voltage or Current. These
four universal inputs are Pin 1 (CH1), Pin 4 (CH2), Pin
7 (CH3), and Pin 10 (CH4). The additional inputs Pin 2
(AI3), Pin 5 (AI6), Pin 8 (AI9), and Pin 11 (AI12) should
be grounded when using the GUI to ensure accurate
measurements of the universal Channel inputs. This can
be achieved by connecting a wire between these pins
and their adjacent GND pins (Pin 3, Pin 6, Pin 9, and
Pin 12). The GUI measures the single-ended channel
inputs using the MAX22005’s multifunctional differential
measurement modes. Using Triplet 1 (AI1, AI2, AI3) as an
example, the voltage is measured differentially from AI1
to AI3. Grounding AI3 is recommended to avoid floating
connections and ensure a more accurate measurement.
After closing SW0, the current is measured by the volt
-
age across the sense resistor from AI1 to AI2. Since the
GUI measures differentially, a differential voltage source
from AI1 to AI3 can also be measured. In all cases, inac
-
curacies due to (potentially long) input wire voltage drops
should be taken into consideration.
When using the MAX22005PMB# with your own soft
-
ware, Pins 2, 5, 8, and 11 (AI3, AI6, AI9, and AI12) can
be used to accommodate other input configurations, for
example to measure a single-ended voltage like the volt
-
age drop across a wire to ground. Refer to Application Note
7413-MAX22005 Universal Analog Input Enables Flexible
Industrial Control Systems for possible example configura
-
tions, in particular the Multifunction Configuration section.
LEDs
The DS1 LED is used to confirm that the Pmod DVDD
is being supplied to the MAX22005PMB# through the J1
connector (pins 6 and 12). The USB2PMB2# DVDD is
3.3V. The DS2 through DS5 are used to indicate if GPIO0
through GPIO3, respectively, are high (LED on) or low
(LED off). The GPIO0 through GPIO3 control switches
SW0 through SW3 which switch in the 49.9Ω precision
sense resistors for the current measurements. Refer to
for a summary of the LED states.
Surge Protection
No external surge suppression is needed as all the
MAX22005 IC analog inputs are protected against up to
±1.5kV surge pulses as per IEC61000-4-5 using series
4.75kΩ 0.4000W resistors.
Table 2. Input Pin Names
Table 3. LED Description
J2 AND J3
CONNECTOR - PIN
PIN
NAME
IC PIN
TRIPLET
J2 - 1
1 (CH1)
AI1
1
J2 - 2
2
AI3
J2 - 3
3
GND
J2 - 4
4 (CH2)
AI4
2
J2 - 5
5
AI6
J2 - 6
6
GND
J3 - 1
7 (CH3)
AI7
3
J3 - 2
8
AI9
J3 - 3
9
GND
J3 - 4
10 (CH4)
AI10
4
J3 - 5
11
AI12
J3 - 6
12
GND
LED
ON
OFF
DS1
DVDD Connected
DVDD Disconnected
DS2
SW0 Closed (CH 1 Current Mode)
SW0 Open (CH1 Voltage Mode)
DS3
SW1 Closed (CH 2 Current Mode)
SW1 Open (CH2 Voltage Mode)
DS4
SW2 Closed (CH 3 Current Mode)
SW2 Open (CH3 Voltage Mode)
DS5
SW3 Closed (CH 4 Current Mode)
SW3 Open (CH4 Voltage Mode)
