Fan 5 Click

How does it work?

Fan 5 Click is based on the TC654, a fan speed controller from Microchip that allows you to control and monitor the speed of two DC brushless fans. The TC654 is based on the FanSense™ technology, which protects your application against fan failure and eliminates the need for 3-wire fans. With the TC654, the fan speed can be controlled by its input voltage or the serial interface, allowing for high flexibility. The input voltage of the TC654 represents temperature, typically provided by a chosen internal or external thermistor (selected through an NTC SEL jumper). The TC654 controls fan speed according to the system temperature by pulse-width modulating the voltage across the fan. This method reduces the fan’s acoustic noise and extends the fan’s working life.

An external N-channel MOSFET, one per channel, controls the fans. Modulating the voltage applied to the gate of the MOSFETs also modulates the voltage applied to the fan. The PWM output can be adjusted between 30% and 100%, based on the TC654’s input voltage, or programmed, as mentioned, via the I2C interface to allow fan speed control without needing an external thermistor. The standard I2C 2-Wire interface reads data and configures settings with a maximum frequency of 100kHz.

The TC654 also measures and monitors fan revolutions per minute (RPM), representing a measure of its health. As a fan’s bearings wear out, the fan slows down and eventually stops (locked rotor). The TC654 can detect open, shorted, unconnected, and locked rotor fan conditions by monitoring the fan’s RPM level. Apart from the availability of this information on the FLT pin of the mikroBUS™ socket, this condition can also be visually detected through the red LED marked with FAULT. The fan RPM data and threshold registers are available over the I2C interface, allowing complete system control.

In addition to the two terminals for fan connections, there is another terminal, VFAN, for an external 12V power supply for FAN1. FAN2 uses the necessary supply from the 5V mikroBUS™ power rail.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

Specifications

Pinout diagram

This table shows how the pinout on Fan 5 Click 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	NC
	NC	2	RST	INT	15	FLT	Fault Indicator
	NC	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	SCL	I2C Clock
	NC	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Fan 5 Click electrical specifications

Software Support

We provide a library for the Fan 5 Click as well as a demo application (example), developed using Mikroe compilers. The demo can run on all the main Mikroe development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Fan 5 Click driver.

Key functions

• fan5_get_rpm1 Fan 5 get speed of FAN1.

• fan5_set_duty_cycle Fan 5 set duty cycle.

• fan5_turn_on_fans Fan 5 turn on fans.

Example Description

This example demonstrates the use of FAN 5 Click board™ by controlling and regulating the fan motors speed.

void application_task ( void )  
 { 
 #if defined FAN_CONTROL_MODE 
     uint16_t speed; 
     uint8_t flag_data; 

     fan5_get_rpm1( &fan5, &speed); 
     log_printf( &logger, " SPEED: %d RPM rn", speed ); 

     if ( FAN5_FAULT == fan5_get_fault_state( &fan5 ) ) 
     { 
         fan5_get_status_flags ( &fan5, &flag_data ); 
         log_printf( &logger, " FLAG: %d rn", flag_data ); 
         if ( FAN5_F1F_FLAG & flag_data ) 
         { 
             log_printf( &logger, " FAN SPEED DROPED !!! rn" ); 
             log_printf( &logger, " OUTPUT IS DISABLED rn" ); 
             fan5_turn_off_fans( &fan5 ); 
             for( ; ; ); 
         } 
     } 

     Delay_ms( 2000 ); 
 #else 
     uint16_t speed; 
     uint8_t duty_value; 

     for ( duty_value = FAN5_30_PER_DUTY; duty_value <= FAN5_100_PER_DUTY; duty_value++ ) 
     { 
         fan5_set_duty_cycle( &fan5, duty_value ); 
         log_printf( &logger, " Duty value: %d rn", ( uint16_t ) duty_value ); 
         Delay_ms( 5000 ); 
         fan5_get_rpm1( &fan5, &speed); 
         log_printf( &logger, " SPEED: %d RPM rn", speed ); 
         Delay_ms( 500 ); 
     } 
 #endif 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Fan5

Additional notes and informations

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. UART terminal is available in all Mikroe compilers.

mikroSDK

This Click board™ is supported with mikroSDK – Mikroe 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.