ST7FMC2R6T6 STMicroelectronics, ST7FMC2R6T6 Datasheet - Page 178

• Manufacturer Part Number: ST7FMC2R6T6
• Description: MCU 8BIT 32K FLASH 64TQFP
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST7FMC2R6T6

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: LINSCI, SPI
• Peripherals: LVD, Motor Control PWM, POR, PWM, WDT
• Number Of I /o: 44
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 3.8 V ~ 5.5 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Processor Series: ST7FMC2x
• Core: ST7
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 60
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: ST7MC-KIT/BLDC, ST7MDT50-EMU3, STX-RLINK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 16 Channel
• For Use With: 497-8402 - BOARD EVAL COMPLETE INVERTER497-8400 - KIT IGBT PWR MODULE CTRL ST7MC497-6408 - BOARD EVAL BLDC SENSORLESS MOTOR497-4734 - EVAL KIT 3KW POWER DRIVER BOARD497-4733 - EVAL KIT 1KW POWER DRIVER BOARD497-4732 - EVAL KIT 300W POWER DRIVER BOARD497-4731 - EVAL KIT PWR DRIVER CONTROL BRD
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 497-4868

ST7MC1xx/ST7MC2xx
MOTOR CONTROLLER (Cont’d)
The
(left axis) and the number of BEMF sampling dur-
ing one electrical step with the corresponding ac-
curacy on the measure (right axis) as a function of
the mechanical frequency.
For a given prescaler value (step ratio register) the
mechanical frequency can vary between two fixed
values shown on the graph as the segment ends.
In autoswitched mode, this register is automatical-
ly incremented/decremented when the step fre-
quency goes out of this segment.
Figure 98. Step Ratio Bits decoding and accuracy results and BEMF Sampling Rate
178/309
1
10
11
12
13
14
15
0
1
2
3
4
5
6
7
8
9
ST[3:0]
Step Ratio (Decimal)
Figure 98
avg Zn ~ FFh ± 0.4%
avg Zn ~ 7Fh ± 0.6%
gives the step ratio register value
avg Zn ~ 55h ± 1.2%
F
step
Fn
Fn+1 = 2.Fn
= 6.N.F
3.Fn
3.Fn+1 = 6.Fn
F
N: Pole pair number
step
rpm
: Electrical step frequency
= N.F / 10 ⇔ N.F = 10.F
200 Hz
At f
tio mechanism goes from 2.39 to 235000 (pole
pair x rpm) with a minimum accuracy of 1.2% on
the step period.
To read the number of samples for Zn within one
step (right Y axis), select the mechanical frequen-
cy on the X axis and the sampling frequency curve
used for BEMF detection (PWM frequency or
measurement window frequency). For example,
for N.Frpm = 15,000 and a sampling frequency of
15kHz, there are approximately 10 samples in one
step and there is a 10% error rate on the measure-
ment.
MTC
avg Zn ~ FFh ± 0.4%
avg Zn ~ 7Fh ± 0.6%
=4MHz, the range covered by the Step Ra-
step
avg Zn ~ 55h ± 1.2%
15 kHz
samples
BEMF
N.Frpm
10
4
2
1
ΔZn/Zn
100%
50%
10%
0%