E-L8150 STMICROELECTRONICS [STMicroelectronics], E-L8150 Datasheet - Page 23

• Manufacturer Part Number: E-L8150
• Description: Brushless motor predriver
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

L8150
5.3
Speed Control Circuitry
The rotation speed control signal (VSP) is an external signal, whose range is 2.1V÷5.4V.
This signal is amplified by an inverting amplifier which takes as reference a voltage derived
from VREG through a voltage divider.
The amplifier output is the input signal of an 8-bit ADC which generates the digital word
KVAL, used to determine the duty cycle value according to the following
Figure 13. Duty cycle
Speed control:
Intout 0-0.7V: duty =100% for smooth drive
(max duty is limited at about 95% for rectangular as shown in the following figure)
Intout 0.7-3.7V: duty control 100-0%
Intout 3.7-4.5: duty = 0 %
Intout 4.5V - 5V (VREG): all power off (all 6 output = GND)
(Each Vth depends linearly on VREG, being obtained by means of voltage dividers).
Operating description
Figure
13:
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