Step Up Klickbrett
Step Up Klickbrett
Overview
Das Step Up Click Board™ ist ein DC-DC-Aufwärtsregler (Boost-Regler) mit fester Frequenz, der von jedem Niederspannungseingang bezogen werden kann – wie NiCd-, NiMH- oder einzelligen Li-Po/Li-Ion-Akkus. Dieses Click bietet einen sehr hohen Wirkungsgrad, geringes Rauschen und eine Anti-Ringing-Spannungsausgabe sowie eine Einschaltstrombegrenzung mit internem Softstart sowie eine echte Trennoption für minimalen Stromverbrauch im Abschaltmodus. Diese Funktionen ermöglichen die Verwendung dieses Geräts als Stromquelle für verschiedene batteriebetriebene Geräte wie Mikrocontroller, verschiedene tragbare eingebettete elektronische Geräte, Handgeräte, GPS-Module oder verschiedene batteriebetriebene USB-Notfall-Backup-Ladegeräte. Ein sehr guter Schaltwirkungsgrad sorgt für eine verlängerte Batterielebensdauer für jede Anwendung, in der dieses Gerät verwendet wird.
Das Step Up Click Board™ wird von einer mikroSDK-kompatiblen Bibliothek unterstützt, die Funktionen enthält, die die Softwareentwicklung vereinfachen. Dieses Click Board™ wird als vollständig getestetes Produkt geliefert und ist bereit für den Einsatz auf einem System, das mit der mikroBUS™-Buchse ausgestattet ist.
The Step Up Click Board™ carries the MCP1665, a high-voltage, 3.6A, integrated switch PFM/PWM boost regulator, available in a 2mm x 2mm VQFN® package, from Microchip. Boost click provides an adjustable output voltage through the onboard DAC that drives the FB pin of the MCP1665 to set desired output voltage. The input voltage can be in range from 2.9V to 5V V from an external DC source connected to VIN screw terminal. The output voltage can be set up to 32V.
How Does The Step Up Click Board™ Work?
The Step Up Click Board™ utilizes the MCP1665, a 500 kHz, compact, high-efficiency, fixed-frequency, nonsynchronous step-up DC-DC converter that integrates a 36V, 100 mΩ NMOS switch, from Microchip. This IC is targeted towards boosting the voltage from NiCd, NiMH, Li-Po/Li-Ion batteries and as such it has a great efficiency factor, that allows for prolonged battery life. The MCP1665 IC uses the fixed switching frequency of 500 kHz and has the overvoltage protection to ensure safe operation.
Thanks to the under-voltage lockout feature, the voltage step-up process starts with the input voltage as low as 2.7V. MCP1665 features an UVLO that prevents fault operation below 2.7V, which corresponds to the value of three discharged primary Ni-Cd cells. The device starts its normal operation at 2.85V (typical) input. For the optimal efficiency, the device should be powered with at least 2.85V at the input terminal. Output current depends on the input and desired output voltage. For example, when powered with 4V at the input, Step Up click will be able to deliver about 1A @ 12V to the connected load. As with the most step-up regulators, the input voltage should always be less than the voltage at the output to maintain the proper regulation. On the diagram below, the dependence of the maximum output current (Iout) on the input and typical output voltages is given.
The MCP1665 step-up regulator actively damps the oscillations typically found at the switch node of a boost converter. This removes the high-frequency radiated noise, ensuring low noise operation.
Besides the MCP1665, Step Up 2 click also contains the D/A converter (DAC) labelled as MCP4921, 12-Bit DACs with the SPI Interface by Microchip, which is used in feedback loop. The DACs is connected to the feedback loop of the boost converter and therefore, the DAC signal which commonly ranges from 0 to +VREF, influences the voltage on the feedback midpoint. That way, the output voltage can be set to a desired value, up to 30V. The mentioned DAC uses SPI communication so the SDI, SDO, SCK, and CS pin of the mikroBUS™ are used for communication with the main MCU.
The device also features the mode pin, labelled as MOD, which is constructed as the open-drain output, that is pulled HIGH by the onboard 10K resistor. This allows an easy interfacing with the MCU and a simple solution to have the control over the switching mode. When the MOD pin is set to logic high level, the device is switching in PFM for light load. The MOD pin is routed to the mikroBUS™ RST pin
Besides the mode pin, the EN pin used to enable the device is routed to the mikroBUS™ CS pin. When pulled LOW, this pin will engage the true disconnect of the output load option, resulting in very low quintessential currents, suitable for the battery-operated devices. This pin is also pulled HIGH by the onboard resistor.
SPECIFICATIONS
Type | Boost |
Applications | Power source for various battery-operated devices, such as microcontrollers, various portable embedded electronic devices, handheld instruments, GPS modules, or various battery-operated USB emergency backup chargers |
On-board modules | MCP1665, a high-voltage, 3.6A, integrated switch PFM/PWM boost regulator |
Key Features | Compact, high-efficiency, fixed-frequency, nonsynchronous step-up DC-DC converter that integrates a 36V, 100 mΩ NMOS switch |
Interface | SPI |
Compatibility | mikroBUS |
Click board size | M (42.9 x 25.4 mm) |
Input Voltage | 5V |
PINOUT DIAGRAM
This table shows how the pinout of the Step Up Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).
Notes | Pin | Pin | Notes | ||||
---|---|---|---|---|---|---|---|
NC | 1 | AN | PWM | 16 | EN | Enable Input | |
Mode input | MOD | 2 | RST | INT | 15 | NC | |
SPI Chip Select | CS | 3 | CS | RX | 14 | NC | |
SPI Clock | SCK | 4 | SCK | TX | 13 | NC | |
SPI Data Out | SDO | 5 | MISO | SCL | 12 | NC | |
SPI Data In | SDI | 6 | MOSI | SDA | 11 | NC | |
NC | 7 | 3.3V | 5V | 10 | 5V | Power Supply | |
Ground | GND | 8 | GND | GND | 9 | GND | Ground |
ONBOARD SETTINGS AND INDICATORS
Label | Name | Default | Description |
---|---|---|---|
LD1 | PWR | - | Power LED Indicator |
TB1 | VIN | - | Input voltage terminal |
TB2 | VOUT | - | Output voltage terminal |
Software Support
We provide a library for the Step Up Click Board™ 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 contains functions for setting states of RST and PWM pins Library contains function for setting configuration word Library contains function for setting output value Library contains function for calculating output value expressed in percent Library contains function for device initialization.
Key Functions
uint8_t stepup_setConfig( uint16_t config )
- sets first 4 bits in command word.uint8_t stepup_setOut( uint16_t out_value )
- sets output value.void stepup_init(void)
- initializes the device.
Example Description
The application is composed of three sections :
- System Initialization - Initializes SPI, LOG, RST, CS and PWM pins
- Application Initialization - Initializes SPI driver, sets config word, initializes the device, sets and log output value
- Application Task - Checks for user input in UART terminal, if user enters + or - output value is increased or decreased respectively
void applicationTask( ) { if (UART_Data_Ready( ) == 1) { uart_char = UART_Read( ); switch ( uart_char ) { case '-' : { if (out_value < 4095) { out_value++; } stepup_setOut( out_value ); stepup_logPercent( out_value ); break; } case '+' : { if (out_value > 0) { out_value--; } stepup_setOut( out_value ); stepup_logPercent( out_value ); break; } default : { mikrobus_logWrite( "error : invalid command", _LOG_LINE ); break; } } } }
Additional Functions :
- stepup_logPercent() - calls 'stepup_getPercent()' function to get output value in expressed as percentage and logs that value
The full application code, and ready to use projects can be found on our LibStock page.
Other mikroE Libraries used in the example:
- SPI
- UART
- Conversions
Additional Notes and Information
Depending on the development board you are using, you may need a 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
Te Step Up Click Board™ is supported with 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.
Software Support
We provide a library for the Step Up Click Board™ 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 contains functions for setting states of RST and PWM pins Library contains function for setting configuration word Library contains function for setting output value Library contains function for calculating output value expressed in percent Library contains function for device initialization.
Key Functions
uint8_t stepup_setConfig( uint16_t config )
- sets first 4 bits in command word.uint8_t stepup_setOut( uint16_t out_value )
- sets output value.void stepup_init(void)
- initializes the device.
Example Description
The application is composed of three sections :
- System Initialization - Initializes SPI, LOG, RST, CS and PWM pins
- Application Initialization - Initializes SPI driver, sets config word, initializes the device, sets and log output value
- Application Task - Checks for user input in UART terminal, if user enters + or - output value is increased or decreased respectively
void applicationTask( ) { if (UART_Data_Ready( ) == 1) { uart_char = UART_Read( ); switch ( uart_char ) { case '-' : { if (out_value < 4095) { out_value++; } stepup_setOut( out_value ); stepup_logPercent( out_value ); break; } case '+' : { if (out_value > 0) { out_value--; } stepup_setOut( out_value ); stepup_logPercent( out_value ); break; } default : { mikrobus_logWrite( "error : invalid command", _LOG_LINE ); break; } } } }
Additional Functions :
- stepup_logPercent() - calls 'stepup_getPercent()' function to get output value in expressed as percentage and logs that value
The full application code, and ready to use projects can be found on our LibStock page.
Other mikroE Libraries used in the example:
- SPI
- UART
- Conversions
Additional Notes and Information
Depending on the development board you are using, you may need a 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
Te Step Up Click Board™ is supported with 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.
Frequently Asked Questions
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