![Performance Motion Devices Juno MC71112 Скачать руководство пользователя страница 79](http://html.mh-extra.com/html/performance-motion-devices/juno-mc71112/juno-mc71112_user-manual_1529620079.webp)
Juno Step Motor Control IC User Guide
79
13
13.Drive & DC Bus Safety
In This Chapter
Drive & DC Bus Safety
Current Foldback
Settable Parameters
Signal Processing
13.1 Drive & DC Bus Safety
The Juno step motor ICs provide sophisticated drive and DC Bus safety features. These features include
overtemperature monitoring, over and under voltage monitoring, overcurrent monitoring, and current foldback.
The following sections provide detailed information for these drive and DC Bus safety related features.
13.1.1 Overtemperature Protection
Juno supports a
Temperature
sensor input to continuously monitor the temperature of the power electronics or another
part of the motion system. Although various temperature sensors may be used, the most common type of sensor is a
thermistor.
The value of the temperature sensor and downstream analog conditioning circuitry determine the overall temperature
range that can be measured. The overall temperature sense range should be 15% to 25% above the highest expected
temperature.
The
Temperature
signal input expects a voltage in the range of 0V to 3.3V representing the sensed temperature. Both
temperature-voltage-increasing (voltage increases with increasing temperature) and temperature-voltage-decreasing
(voltage decreases with increasing temperature) thermistors are supported. For voltage increasing thermistors 0.0V
represents the lowest possible temperature, and for voltage decreasing thermistors 3.3V represents the lowest possible
temperature.
The overtemperature threshold is user programmable. The sign of the overtemperature threshold selects whether the
Temperature
input increases or decreases with rising temperature; positive thresholds indicate voltage increase while
negative thresholds indicate voltage decrease. The actual limit threshold utilized by Juno for the comparison is the
absolute value of the specified limit value. The magnitude of the numerical threshold value has a range of 0 to 32,767
with 0 being the lowest readable temperature and 32,767 the highest.
In addition to the settable overtemperature threshold Juno supports a settable temperature hysteresis. This function is
used to avoid spurious re-triggering of an overtemperature event.
Example
A temperature-voltage-increasing thermistor and associated analog processing circuitry generate a voltage of 2.9V when
the amplifier is at the hottest safely operable temperature. The overtemperature limit specified should thus be set to
32,768 * 2.9V/3.3V = 28,796. Later the design is changed so that a voltage decreasing thermistor is used. With a voltage
decreasing thermistor an overtemperature limit of -28,796 would be programmed.
Содержание Juno MC71112
Страница 12: ...The Juno IC Family 12 Juno Step Motor Control IC User Guide 1 This page intentionally left blank ...
Страница 18: ...Functional Characteristics 18 Juno Step Motor Control IC User Guide 2 This page intentionally left blank ...
Страница 22: ...Electrical Characteristics 22 Juno Step Motor Control IC User Guide 3 This page intentionally left blank ...
Страница 26: ...Timing Diagrams 26 Juno Step Motor Control IC User Guide 4 This page intentionally left blank ...
Страница 46: ...Operational Overview 46 Juno Step Motor Control IC User Guide 7 This page intentionally left blank ...
Страница 54: ...Microstep Waveform Generation 54 Juno Step Motor Control IC User Guide 8 This page intentionally left blank ...
Страница 70: ...Internal Profile Generation 70 Juno Step Motor Control IC User Guide 11 This page intentionally left blank ...
Страница 78: ...Motion Monitoring Control 78 Juno Step Motor Control IC User Guide 12 This page intentionally left blank ...
Страница 86: ...Drive DC Bus Safety 86 Juno Step Motor Control IC User Guide 13 This page intentionally left blank ...
Страница 100: ...Application Notes MC74113 MC75113 100 Juno Step Motor Control IC User Guide 15 Figure 15 3 Drive Safety and Monitoring ...
Страница 103: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 103 15 Figure 15 4 Leg Current Sensing ...
Страница 114: ...Application Notes MC74113 MC75113 114 MC58113 Electrical Specifications 15 This page intentionally left blank ...