L6229QTR STMicroelectronics, L6229QTR Datasheet - Page 18

• Manufacturer Part Number: L6229QTR
• Description: IC DRIVER DMOS DC MOTOR 32VFQFPN
• Manufacturer: STMicroelectronics
• Type: 3 Phase Brushless DC Motor Driverr

Specifications of L6229QTR

• Applications: DC Motor Driver, Brushless (BLDC), 3 Phase
• Number Of Outputs: 1
• Current - Output: 2.8A
• Voltage - Supply: 12 V ~ 52 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN, 32-VFQFPN
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-8495-2

Circuit description
5.6
18/28
Tacho
A tachometer function consists of a monostable, with constant off time (t
is one hall effect signal (H
external op amp, as shown in
Information section.
The monostable output drives an open drain output pin (TACHO). At each rising edge of the
hall effect sensors H
TACHO is turned off for a constant time t
set using the external RC network (R
gives the relation between t
t
where C
20 kΩ … 100 kΩ.
By connecting the tachometer pin to an external pull-up resistor, the output signal average
value V
speed. This realizes a simple frequency-to-voltage converter. An op amp, configured as an
integrator, filters the signal and compares it with a reference voltage V
speed of the motor.
Figure 16. Tacho operation waveforms
PULSE
= 0.6 · R
M
PUL
is proportional to the frequency of the hall effect signal and, therefore, to the motor
should be chosen in the range 1 nF … 100 nF and R
PUL
V
· C
1
TACHO
, the monostable is triggered and the MOSFET connected to pin
V
H
H
H
PUL
M
1
2
3
1
). It allows developing an easy speed control loop by using an
PULSE
Figure
Doc ID 15209 Rev 3
and C
t
PULSE
V
17. For component values refer to Application
PUL
M
PUL
PULSE
, C
=
t
----------------- - V
PUL
PULSE
, R
V
T
DD
T
PUL
) connected to the pin RCPULSE.
(see
⋅
. We have approximately:
DD
Figure
16). The off time t
PUL
in the range
REF
PULSE
, which sets the
PULSE
), whose input
Figure 18
L6229Q
can be