MIC24055 click
PID: MIKROE-2835
Weight: 35 g
MIC24055 click is the buck regulator that can deliver continuous output current up to 8A and
can step down voltages from up to 19V which makes this click board easy to use with many
power sources commonly available. The amount of current it can deliver and the steady, ripplefree regulated voltage, make this click board a perfect choice for powering up devices which
require high current, regulated power supply, such as servers and workstations, routers, telecom
equipment and every other electronic device with similar power demands.
MIC24055 click is equipped with the MIC24055, high-efficiency buck regulator from
Microchip. This IC can work with the wide range of input voltages, from 4.5V up to 19V. The
regulated voltage at the output can be set from 1V to 4.8V by the means of the feedback (FB) pin
and the second chip on board - MCP4921, a single channel 12-bit DAC by Microchip, equipped
with the SPI interface. By programming the output of this DAC through the SPI interface routed
to the mikroBUS socket pins, it is possible to easily set up the output voltage of the buck
regulator. MikroElektronika libraries make it possible to perform this task easily, as seen in the
example application.
How does the MIC24055 click work?
The MIC24055 IC is used on this click board as the main buck regulating element. It is a
synchronous buck regulator from Microchip, which works with the fixed switching frequency of
600kHz, featuring a unique adaptive on-time control architecture. This buck regulator accepts
input voltages from 4.5V to 19V and outputs voltage from 1V to 4.8V. The buck regulator IC
provides a full suite of safekeeping features to ensure the protection of the IC during fault
conditions, such as the under-voltage lockout, internal soft-start to reduce inrush current, shortcircuit protection and thermal shutdown. MIC24055 click is capable of delivering up to 8A of
continuous output current on its output connector.
To set the desired output voltage, the MIC24055 relies on the feedback voltage of the FB pin.
For that purpose, the FB pin of the MIC24055 is connected to the MCP4921 DAC converter
VOUT pin. The MCP4921 DAC uses the SPI interface and it can be programmed to output a
specific voltage level to the FB pin of the buck regulator. That way, the output voltage of the
buck regulator can be adjusted to the desired level. The buck regulator output voltage is also fed
back to the AN pin of the click board, through the voltage divider. This allows for checking the
output voltage of the regulator, so the software can additionally adjust the level of the DAC
output if needed. For the proper operation of the device, the input voltage needs to be greater
than the set output voltage.
Besides the AN pin, the click board uses the SPI interface pins, EN pin - which is used to enable
the buck regulator chip and the INT pin, which is routed to the PG pin of the MIC24055 buck
regulator. This pin is an open drain output pin, used to signalize the Power Good condition,
which occurs when the output voltage level (VOUT) reaches 92% of its steady state voltage
level. This pin is supplied with the pull-up resistor, connected to the 3.3V rail.
The click board is also equipped with the two 18A connectors, for an easy and secure connection
of the input and output lines.
Specifications
Type
Buck
The MIC24055 click can be used for powering up devices which require regulated power
Applications source with sufficient current, such as servers and work stations, routers, telecom
equipment and every other electronic device with similar power demands.
On‐board
modules
Microchip's MIC24055 constant‐frequency synchronous buck regulator. Microchip's
MCP4921 single channel, 12‐bit DAC with the SPI interface.
Key Features
Continuous output current up to 8A, wide input range from 4.5V to 19V, power good
(PG) output, short circuit protection, under‐voltage protection, fast transient response.
Interface
Analog,GPIO,SPI
Input Voltage 3.3V
Click board
size
L (57.15 x 25.4 mm)
Pinout diagram
This table shows how the pinout on MIC24055 click corresponds to the pinout on the
mikroBUS™ socket (the latter shown in the two middle columns).
Notes
Pin
Pin
Notes
Analog In
AN
1
AN
PWM
16
NC
MIC24055 Enable
EN
2
RST
INT
15
INT
DAC Chip Select
CS
3
CS
RX
14
NC
Power Good Out
SPI Clock
SCK
4
SCK
TX
13
NC
NC
5
MISO
SCL
12
NC
SPI SDI
MOSI
6
MOSI
SDA
11
NC
Power Supply
+3.3V
7
3.3V
5V
10
NC
Ground
GND
8
GND
GND
9
GND
Ground
MIC24055 click electrical specifications
Description
Min Typ Max Unit
VIN
4.5
19
V
4.8
V
8
A
VOUT
1
Continuous output current
Onboard settings and indicators
Label
Name
Default
Description
PWR Power LED
‐
Power LED indicator
TB1
VIN
‐
Connector for connecting external VIN
TB2
VOUT
‐
Connector for connecting the load
Software support
We provide a library for MIC24055 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
The library contains functions for basic control of the onboard DAC.
Key functions:
void mic24055_dacOutput(uint16_t valueDAC)- Directly sets the DAC output voltage
void mic24055_setVout(uint16_t voltage)- Sets the output voltage
Examples Description
The application is composed of three sections :
System Initialization ‐ Initializes pin and peripherals
Application Initialization ‐ Initializes the click driver
Application Task ‐ Slowly alternates the click output between two values
mic24055_setVout(500);
mikrobus_logWrite("Setting Vout to 500mV",_LOG_LINE);
Delay_ms(3000);
mic24055_setVout(2300);
mikrobus_logWrite("Setting Vout to 2300mV",_LOG_LINE);
Delay_ms(3000);
The full application code, and ready to use projects can be found on our LibStock page.
Other MikroElektronika libraries used in the example:
UART
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.
https://www.mikroe.com/mic24055‐click 12‐20‐17