Datasheet

Circuit description L6229Q
12/28 Doc ID 15209 Rev 3
5.2 Logic inputs
Pins FWD/REV, BRAKE, EN, H1, H2 and H3 are TTL/CMOS and microcontroller compatible
logic inputs. The internal structure is shown in Figure 6. Typical value for turn-on and turn-off
thresholds are respectively V
th(ON)
= 1.8 V and V
th(OFF)
= 1.3 V.
Pin EN (Enable) has identical input structure with the exception that the drain of the
Overcurrent and thermal protection MOSFET is also connected to this pin. Due to this
connection some care needs to be taken in driving this pin. The EN input may be driven in
one of two configurations as shown in Figure 10 or Figure 11. If driven by an open drain
(collector) structure, a pull-up resistor R
EN
and a capacitor C
EN
are connected as shown in
Figure 10. If the driver is a standard Push-Pull structure the resistor R
EN
and the capacitor
C
EN
are connected as shown in Figure 11. The resistor R
EN
should be chosen in the range
from 2.2 kΩ to 180 kΩ. Recommended values for R
EN
and C
EN
are respectively 10 kΩ and
5.6 nF. More information on selecting the values is found in the overcurrent protection
section.
Figure 6. Logic inputs internal structure
Figure 7. Pin EN open collector driving
Figure 8. Pin EN push-pull driving
5V
D01IN1329
ESD
PROTECTION
5V
5V
OPEN
COLLECTOR
OUTPUT
R
EN
C
EN
EN
DIAG
D02IN137
8
ESD
PROTECTION
5V
PUSH-PULL
OUTPUT
R
EN
C
EN
EN
D02IN137
9
DIAG
ESD
PROTECTION