L6235QTR STMicroelectronics, L6235QTR Datasheet - Page 12

• Manufacturer Part Number: L6235QTR
• Description: Motor / Motion / Ignition Controllers & Drivers DMOS 3-Phase Brushless DC Motor
• Manufacturer: STMicroelectronics

Specifications of L6235QTR

• Product Category: Motor / Motion / Ignition Controllers & Drivers
• Rohs: yes

Circuit description
12/33
Figure 10. Output current regulation waveforms
Figure 11
be approximately calculated from the equations:
where R
dead time with:
therefore:
These values allow a sufficient range of t
The capacitor value chosen for C
pin R
before the next time the monostable is triggered. Therefore, the ON time t
depends on motors and supply parameters, must be bigger than t
current regulation by the PWM stage. Furthermore, the ON time t
the minimum ON time t
t
t
20 kΩ ≤ R
0.47 nF ≤ C
t
t
t
COFF
RCFALL
OFF
DT
OFF(MIN)
OFF(MAX)
R
V
OFF
= 1 µs (typical value)
V
SENSE
SENSE
I
OUT
= t
V
REF
. The rise time t
2.5V
OFF
V
shows the magnitude of the OFF time t
ON
5V
REF
0
RC
= 0.6 · R
RCFALL
and C
= 6.6 µs
OFF
= 6 ms
SYNCHRONOUS RECTIFICATION
D02IN1351
OFF
OFF
≤ 100 kΩ
+ t
OFF
≤ 100 nF
DT
are the external component values and t
ON(MIN)
· C
= 0.6 · R
RCRISE
OFF
Doc ID 018997 Rev 2
.
is only an issue if the capacitor is not completely charged
OFF
OFF
also affects the rise time t
B
· C
Slow Decay
t
OFF
RCFALL
OFF
1μs t
t
1μs t
t
RCRISE
OFF
C
to implement the drive circuit for most motors.
+ t
BLANK
DT
DT
OFF
D
versus C
t
ON
A
B
OFF
DT
Slow Decay
RCRISE
t
RCFALL
ON
1μs t
t
1μs t
t
is the internally generated
RCRISE
RCRISE
OFF
C
and R
can not be smaller than
BLANK
DT
of the voltage at the
OFF
D
to allow a good
ON
, which
values. It can
L6235Q