ST7FMC1K2B3 STMICROELECTRONICS [STMicroelectronics], ST7FMC1K2B3 Datasheet - Page 186

• Manufacturer Part Number: ST7FMC1K2B3
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ST7MC1xx/ST7MC2xx
MOTOR CONTROLLER (Cont’d)
10.6.8.2 Over Current Handling in Voltage
mode
When the current limitation interrupt is enabled by
setting the CLIM bit in the MIMR register (available
only in Voltage mode), the OCV bit in MCRB reg-
ister will determine the effect of this interrupt on
the MCOx outputs as shown in
Table 43. OCV bit effect
For safety purposes, it can be necessary to put all
MCOx outputs in reset state (high impedance,
high state or low state depending on the setting
made by the option byte) on a current limitation in-
terrupt. This is the purpose of the OCV bit. When a
current limitation interrupt occurs, if the OCV bit is
reset, the effect on the MCOx outputs is only to put
the PWM signal OFF on the concerned outputs. If
the OCV bit is set, when the current limitation inter-
rupt occurs, all the MCOx outputs are put in reset
state.
Note 1: Only this functionality (CLIM = CLI = OCV
= 1) is valid when the 3 PWM channels are ena-
bled (PCN bit =1 in the MDTG register). It can also
be used as an over-current protection for three-
phase PWM application (only if voltage mode is
selected)
10.6.8.3 Current Mode
In current mode, the PWM output signal is gener-
ated by a combination of the output of the meas-
urement window generator (see
the output of the current comparator, and is direct-
ed to the output channel manager as well
108).
The current reference is provided to the compara-
tor by Phase U, V or W of the PWM Generator (up
to 12-bit accuracy) the signal from the three com-
pare registers U, V or W can be output by setting
186/309
1
CLIM bit CLI bit OCV bit
0
0
1
1
1
0
1
0
1
1
0
1
x
x
x
All MCOx outputs
PWM is put OFF
PWM is put OFF
on Current loop
on Current loop
Normal running
Normal running
are put in reset
state (MOE re-
Output effect
mode
mode
effect
effect
set)
Table
1)
Figure
43.
107) and
Interrupt
(Figure
Yes
Yes
No
No
No
the PWMU, PWMV or PWMW bits in the MPWME
register. The PWM signal is filtered through an ex-
ternal RC filter on pin MCCREF.
The detected current input must be present on the
MCCFI pin.
10.6.8.4 Current Feedback Comparator
Two programmable filters are implemented:
– A blanking window ( Current Window Filter) after
– An event counter (Current Feedback Filter) to
Figure 105. Current Window and Feedback
Filters
PWM has been switched ON to avoid spurious
PWM OFF states caused by parasitic noise
prevent PWM being turned OFF when the first
comparator edge is detected.
Reset counter
No
No
No
Increment counter
Blanking Window
Set the CL bit
Yes
Current >
Counter=
PWM on
End of
Limit?
Limit
?
?
Yes
No
FEEDBACK
CURRENT
CURRENT
WINDOW
FILTER
FILTER
Yes
Yes
Limit=1?