# L6258

Manufacturer Part NumberL6258
ManufacturerSTMicroelectronics
L6258 datasheet

## Specifications of L6258

Operating Current15mAMotor Controller TypePWM Motor Controller
Package TypePowerSOOperating Supply Voltage (min)12V
Operating Supply Voltage (typ)34VOperating Supply Voltage (max)5.25V
Lead Free Status / Rohs StatusNot Compliant
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PWM current control loop
Moreover, having the two references Tri_0 and Tri_180 a triangular shape it is clear that the
transfer function of this block is a linear constant gain without poles and zeros.
3.3
The load block is composed by the equivalent circuit of the motor winding (resistance and
inductance) plus the sense resistor.
We will considered the effect of the Bemf voltage of the motor in the next chapter.
The input of this block is the PWM voltage of the power amplifier and as output we have the
voltage across the sense resistor produced by the current flowing into the motor winding.
The relation between the two variable is:
so the gain of this block is:
where:
R
= equivalent resistance of the motor winding
L
R
= sense resistor
S
Because of the inductance of the motor L
18/32
2 24
ACpw
20
log
------------- -
=
dB
1.6
V out
---------------------- R
V sense
=
S
R
R
+
L
S
V sense
=
-------------------- -
=
----------------------
v
R
out
R S
20
log
----------------------
=
R L
0.33
----------------------- -
=
20
log
12
+
0.33
, the load has a pole at the frequency:
L
1
Fpole
=
-------------------------------- -
L
L
-------------------- -
R
R
+
L
1
Fpole
=
---------------------------------------- -
=
3
12 10
----------------------- -
6.28
12
+
0.33
29.5dB
=
R S
+
R
L
S
+
R S
=
31.4dB
S
163Hz
L6258