L6208
5.2
Circuit description
Logic inputs
Pins CONTROL, HALF/FULL, CLOCK, RESET and CW/CCW are TTL/CMOS compatible
logic inputs. The internal structure is shown in Figure 9. Typical value for turn-on and turn-off
thresholds are respectively Vth(ON) = 1.8 V and Vth(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 REN and a capacitor CEN are connected as shown in
Figure 10. If the driver is a standard Push-Pull structure the resistor REN and the capacitor
CEN are connected as shown in Figure 11. The resistor REN should be chosen in the range
from 2.2 K to 180 K. Recommended values for REN and CEN are respectively 100 K and
5.6 nF. More information on selecting the values is found in Section 7.5: Non-dissipative
overcurrent protection on page 21.
Figure 9. Logic inputs internal structure
9
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Figure 10. EN pin open collector driving
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Figure 11. EN pin push-pull driving
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