ONE SHOT CLICK
PID: MIKROE-3877
Weight: 19 g
One Shot Click is equipped with the monostable multivibrator (also known as a “oneshot” pulse generator) with a programmable pulse width of 1μs to 33.6 seconds. The
used LTC6993-2 is part of the TimerBlox® family of versatile silicon timing devices, from
Analog Devices. In addition to this, One Shot Click also offers configurability for either
positive or negative output pulse, fast recovery time, 70μA supply current, CMOS output
driver 20mA sources/sinks and many more useful features, which makes this Click
board™ an ideal choice for applications such as watchdog timers, frequency
discriminators, missing pulse detection, envelope detection and more.
One Shot Click board™ is supported by a mikroSDK compliant library, which includes
functions that simplify software development. This Click board™ comes as a fully tested
product, ready to be used on a system equipped with the mikroBUS™ socket.
HOW DOES IT WORK?
One Shot click is equipped with the LTC6993-2, a monostable multivibrator (also known
as a “one-shot” pulse generator) with a programmable pulse width of 1μs to 33.6
seconds, from Analog Devices. The LTC6993-2 is part of the TimerBlox® family of
versatile silicon timing devices. A single resistor, RSET, programs an internal master
oscillator frequency, setting the LTC6993’s time base. The output pulse width is
determined by this master oscillator and an internal clock divider, NDIV, programmable
to eight settings from 1 to 221.
The output pulse is initiated by a transition on the trigger input (TRIG). Each part can be
configured to generate positive or negative output pulses. The LTC6993-2 is available in
four versions to provide different trigger signal polarity and retrigger capability. Besides
that, LTC6993-2 also offers the ability to dynamically adjust the width of the output pulse
via a separate control voltage, brought to the SET pin of the IC. Simple trimmer or
potentiometer could be used, however due to reliability reasons, on One Shot
Click, AD5241 digital potentiometer is used for that purpose. The word is about a 256position digital potentiometer with low temperature coefficient (30 ppm/°C), also from
Analog Devices. The AD5241 communicates with the microcontroller over the standard
I2C interface, so that user can easily control and precisely calculate the output pulse
width just with simple setting the wiper value in the AD5241 registers.
One Shot Click also contains the multi-turn trimmer wired as a a resistor divider
between V+ and GND and brought to the DIV pin of the LTC6993-2. The DIV pin is the
programmable divider and polarity input. The polarity input which pin voltage is
internally converted into a 4-bit result (DIVCODE). The MSB of DIVCODE (POL)
determines the polarity of the OUT pins. When POL = 0 the output produces a positive
pulse. When POL = 1 the output produces a negative pulse. That way, user can easily
set the output pulse width range and polarity, just by setting the desired voltage on the
mentioned trimmer (VR1). This click board also contains test points in order to ease the
access to the referent voltage to the user. One can simply separate the trimmer from
the rest of the circuit using the separation switch (SW1), then precisely set and measure
the desired voltage and then turn the switch back in the ON position.
One Shot Click is equipped with on-board SMD jumper labeled as the VCC SEL, which
is used to select the operating voltage level, consequently limiting the amplitude of the
output signal in respect to the selected voltage. That enables a selection between 3.3V
and 5V operation, with the onboard SMD jumper, labeled as VCC SEL. This allows both
3.3V and 5V MCUs to be interfaced with this Click board™.
SPECIFICATIONS
Type
Signal generator,Clock generator
Applications
Ideal choice for applications such as watchdog timers, frequency
discriminators, missing pulse detection, Envelope Detection and more.
On-board
modules
LTC®6993 - a monostable multivibrator (also known as a “one-shot”
pulse generator) with a programmable pulse width from analog devices
AD5241 - 256-Position Digital Potentiometer
Key Features
Configurability for positive or negative output pulse, fast recovery time,
70μA supply current, CMOS output driver 20mA sources/sinks and many
more
Interface
GPIO,I2C
Compatibility
mikroBUS
Click board
size
M (42.9 x 25.4 mm)
Input Voltage
3.3V or 5V
PINOUT DIAGRAM
This table shows how the pinout on One Shot 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
Output signal
OUT
2
RST
INT
15
NC
Trigger input
TRG
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
Ground
GND
8
GND
GND
9
GND
Power supply
Ground
ONBOARD SETTINGS AND INDICATORS
Label
Name
Default
LD1
PWR
-
JP1
VCC SEL
Left
SW1
SEPARATION
Right
Description
Power LED Indicator
Power supply voltage selection: left position
3V3, right position 5V
VDIV voltage separation switch
SOFTWARE SUPPORT
We provide a library for the One Shot 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 covers all the necessary functions to control One Shot Click. User can use
functions to set or check state of AD5241, set or clear trigger pin and check output pin.
Key functions:
void oneshot_setTrig( uint8_t state ) - Changes the state of trigger pin.
uint8_t oneshot_checkOut() - Checks the state of output pin.
float oneshot_getR() - Calculates resistance of AD5241.
Examples description
The application is composed of three sections :
System Initialization - Initializes I2C and LOG structures, sets CS pin as output and RST pin as
input.
Application Initialization - Initialization driver enables I2C and also starts write log.
Application Task - (code snippet) This example demonstrates the use of One Shot click. When value
0x18 is applied on AD5241, trigger pin is cleared and ressistance between TP1 i TP2 is set to 27
kohm, One Shot click produces one 0.5s pulse.
void applicationTask()
{
oneshot_setTrig( 0 );
}
The full application code, and ready to use projects can be found on our LibStock page.
Other Mikroe Libraries used in the example:
I2C
UART
Conversions
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. 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 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.
For more information about mikroSDK, visit the official page.
https://www.mikroe.com/one‐shot‐click/1‐28‐20