Nano Power 2 click
PID: MIKROE‐3036
Weight: 26 g
Nano Power 2 click is a very low power voltage comparator, aimed at portable and batterypowered applications. It allows detecting a difference of two voltage potentials, applied on two
input pins. The device can detect differences very precisely, avoiding oscillations that can occur
when both input voltages are equal by employing an internal hysteresis. Nano Power 2 click
offers a choice to select one of the input voltages from the internal fixed reference of 1.2V, or by
setting both input voltages by the onboard potentiometers.
The current consumption of the Nano Power 2 click ensures that there is no significant
load to the measured inputs, and compared to other similar devices, it is several
magnitudes lower. It produces clean output signals, which are used to indicate the result
of the comparison. Both the logic level and the power supply levels can be selected
between 3.3V and 5V, allowing a wide range of MCUs to be used with this Click board™.
With its two high-quality potentiometers, this Click board™ represents a unique testing
platform for the integrated nanoPower comparator IC used on the Nano Power 2 click.
How does it work?
The Click board™ is equipped with an integrated comparator IC, labeled
as MAX40000AUT12+, a nanoPower comparator with built-in reference, produced
by Maxim Integrated. This company offers several variants of the same IC, of which the
used IC variant offers reference voltage of 1.2V on one of its pins. This reference voltage
can be used at the comparator input, providing an accurate reference voltage
throughout the fully operational temperature range, if required by the custom
application.
The IC itself requires a very low number of external components. It has two input pins,
used as the comparator inputs. Each of these inputs can use -0.2V up to VCC + 0.2V. The
VCC is the power supply voltage, and it can be selected via the SMD jumper labeled as
LOGIC, between the 3.3V and 5V rails from the mikroBUS™. One of the comparator
inputs, labeled as IM on the MAX40000 IC, is routable to either the onboard
potentiometer (P1) or the REF pin of the IC, which provides the referent voltage of 1.2V.
The routing can be done by another SMD jumper, labeled as REF SEL. The second
comparator input (labeled as IP on the MAX40000 IC) is routed to the second onboard
potentiometer (P2). Both potentiometers can be used to set any voltage between the
GND and VCC, which is selected by the LOGIC jumper, as described above.
As mentioned before, the comparator has two inputs. One of them it is the inverting
input and it is labeled as IM. The other input is a non-inverting input, labeled as IP.
When the IP voltage becomes higher than the IM voltage, the output state becomes
logic HIGH; otherwise, the output is set to a LOW state. A special case is when both
voltages are very close, or at the same level, at any given moment. This would result in
an appearance of oscillation at the output due to noise or parasitic feedback. To cope
with this problem, an internal hysteresis of ±2.5mV is applied.
The output of the MAX40000 IC is routed to the mikroBUS™ INT pin, labeled as OUT on
the Click board™. The output stage employs a unique break-before-make topology,
capable of rail-to-rail operation with up to ±2mA loads. The output stage also uses a
unique design, which minimizes supply current surges when the switching occurs,
resulting in very clean output and low EM radiation. The MAX40000 has a push-pull
output stage topology, which can both sink and source the current.
Working with the Nano Power 2 click is very easy and straightforward. Only a single pin
is used, which can be used to either trigger an interrupt (therefore it is routed to the INT
pin), or its status can be read via the input pin of the host MCU. However,
MikroElektronika provides a library that contains a function which can be used for
simplified control of the Nano Power 2 click. The library also contains an example
application, which demonstrates the use of the function. This example application can
be used as a reference for custom designs.
Specifications
Type
Linear
It can be used for a voltage level comparison between two
Applications
comparator pins, selectable by a potentiometer, or from the internal
reference voltage pin.
On-board
MAX40000, a nanoPower comparator with built-in reference,
modules
produced by Maxim Integrated
Key Features
Two high quality potentiometers for selecting the voltage at the
comparator pins, an accurate reference voltage of 1.2V, hysteresis
which prevents erratic behavior when the input voltages are close
to each other.
Interface
GPIO
Input Voltage
3.3V,5V
Click board
size
M (42.9 x 25.4 mm)
Pinout diagram
This table shows how the pinout on Nano Power 2 click corresponds to the pinout on
the mikroBUS™ socket (the latter shown in the two middle columns).
Notes
Pin
Pin
NC
1
AN
PWM
16
NC
NC
2
RST
INT
15
OUT
NC
3
CS
RX
14
NC
NC
4
SCK
TX
13
NC
NC
5
MISO
SCL
12
NC
NC
6
MOSI
SDA
11
NC
NC
7
3.3V
5V
10
+5V
Notes
Comparator OUT
Power supply
Ground
8
GND
GND
GND
9
GND
Ground
Nano Power 2 click electrical specifications
Description
Input reference voltage
Min
Typ
Max
Unit
-
1.2
-
V
Onboard settings and indicators
Label
Name
Default
Description
LD1
PWR
-
JP1
REF SEL
Right
Reference voltage source selection: left position internal
reference voltage, right position P1 voltage
JP2
LOGIC
Right
Power supply / logic voltage level selection: left position
3.3V, right position 5V
Power LED indicator
Software support
We provide a demo application for Nano Power 2 click on our Libstock page, as well as a
demo application (example), developed using MikroElektronika compilers. The demo
can run on all the main MikroElektronika development boards.
Library Description
Library initializes and defines GPIO driver and performs control of device voltage.
For more details check the documentation.
Key functions:
NANOPW2_RETVAL_T nanopw2_checkOutput( void ) - TFunction gets output voltage from
comparator.
Example description
The application is composed of three sections:
System Initialization - Initializes OUT (INT) pin as an input.
Application Initialization - Initializes GPIO driver.
Application Task - (code snippet) - Checks the comparator's output and logs output value on
USB UART. The hysteresis in a comparator creates two trip points: one for upper threshold
(VTRIP+) and one for lower threshold (VTRIP-) for voltage transitions on the input signal. When
the comparator’s input voltages are equal, the hysteresis effectively causes one comparator
input to move quickly past the other, thus taking the input out of the region where oscillation
occurs. The output voltage is high (1) when noninverted input voltage rises above the hysteresis
and stays high until noninverted input voltage falls below the hysteresis. Then the output goes
low and stays low until noninverted input voltage rises above the hysteresis. This is an example
where the inverted input voltage is fixed and the noninverted input voltage is varied. If the inputs
were reversed, the example would be the same, except with an inverted output.
void applicationTask()
{
outCheck = nanopw2_checkOutput();
if (outCheck != outCheckPrev)
{
WordToStr( outCheck, text );
mikrobus_logWrite( "OUT is: ", _LOG_TEXT );
mikrobus_logWrite( text, _LOG_LINE );
outCheckPrev = outCheck;
}
}
The full application code, and ready to use projects can be found on our Libstock page.
Additional notes and information
Depending on the development board you are using, you may need USB UART
click, USB UART 2 click or RS232 click to connect to your PC, for development systems
with no UART to USB interface available on the board. The terminal available in all
MikroElektronika compilers, or any other terminal application of your choice, can be
used to read the message.
mikroSDK
This click board is supported by mikroSDK - MikroElektronika Software Development Kit.
To ensure proper operation of mikroSDK compliant click board demo applications,
mikroSDK should be downloaded from the LibStock and installed for the compiler you
are using.
For more information about mikroSDK, visit the official page.
https://www.mikroe.com/nano‐power‐2‐click 6‐15‐18