L6208QTR STMicroelectronics, L6208QTR Datasheet - Page 18

• Manufacturer Part Number: L6208QTR
• Description: Motor / Motion / Ignition Controllers & Drivers DMOS Dual Full Bridge Driver 5.6A
• Manufacturer: STMicroelectronics

Specifications of L6208QTR

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

Circuit description
4.9
18/33
Figure 18. Half step mode
Figure 19. Normal drive mode
Figure 20. Wave drive mode
Non-dissipative overcurrent detection and protection
The L6208 integrates an overcurrent detection circuit (OCD). With this internal overcurrent
detection, the external current sense resistor normally used and its associated power
dissipation are eliminated.
detection circuit.
To implement overcurrent detection, a sensing element that delivers a small but precise
fraction of the output current is implemented with each high-side power MOSFET. Since this
current is a small fraction of the output current, there is very little additional power
dissipation. This current is compared with an internal reference current I
output current reaches the detection threshold (typically 5.6 A), the OCD comparator signals
a fault condition. When a fault condition is detected, the EN pin is pulled below the turn-off
threshold (1.3 V typical) by an internal open drain MOSFET with a pull-down capability of 4
mA. By using an external R-C on the EN pin, the OFF time before recovering normal
operation can be easily programmed by means of the accurate thresholds of the logic
inputs.
Start Up or Reset
Start Up or Reset
Start Up or Reset
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Figure 21
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Doc ID 018710 Rev 2
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D01IN1320
D01IN1321
D01IN1322
shows a simplified schematic of the overcurrent
CLOCK
CLOCK
CLOCK
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I
OUTA
OUTB
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I
I
I
OUTA
OUTB
OUTA
OUTB
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REF
. When the
L6208Q