# L6258EX STMicroelectronics, L6258EX Datasheet - Page 19

#### L6258EX

Manufacturer Part Number
L6258EX
Description
IC MOTOR DRIVER UNIV 36-PWRSOIC
Manufacturer
STMicroelectronics
Type
Driverr
Datasheet

#### Specifications of L6258EX

Applications
DC Motor Driver, Stepper Motor Driver
Number Of Outputs
2/1
Current - Output
1.5A
12 V ~ 40 V
Voltage - Supply
4.75 V ~ 5.25 V
Mounting Type
Surface Mount
Package / Case
Operating Supply Voltage
12 V to 40 V
Supply Current
15 mA
Mounting Style
SMD/SMT
Operating Temperature
150 C
Lead Free Status / RoHS Status
Operating Temperature
-
Lead Free Status / Rohs Status
Other names
497-3702-5
E-L6258EX

#### Available stocks

Company:
Bonase Electronics (HK) Co., Limited
Part Number:
L6258EX
Manufacturer:
WOLFSON
Quantity:
1 440
Price:
L6258EX
3.4
Before analysing the error amplifier block and the sense transconductance block, we have to
do this consideration:
Aloop
Ax|
and
Bx|
this means that Ax|dB is the sum of the power amplifier and load blocks;
Ax|
The BODE analysis of the transfer function of Ax is:
Figure 7.
The Bode plot of the Ax|dB function shows a DC gain of -1.9dB and a pole at 163Hz.
It is clear now that (because of the negative gain of the Ax function), Bx function must have
an high DC gain in order to increment the total open loop gain increasing the bandwidth too.
Error amplifier and sense amplifier
As explained before the gain of these two blocks is:
Bx
Being the voltage across the sense resistor the input of the Bx block and the error amplifier
voltage the output of the same, the voltage gain is given by:
dB
dB
dB
dB
= ACerr
dB
= ACpw|
= ACerr|
= (29,5) + (-31.4) = -1.9dB
= Ax
Ax bode plot
dB
dB
dB
dB
+ Bx
+ ACsense
+ ACsense|
dB
ib
dB
dB
dB
=
Vsense
Gs
=
Vsense
------- -
Rb
1
PWM current control loop
19/32