ATA6824-DK Atmel, ATA6824-DK Datasheet - Page 12

• Manufacturer Part Number: ATA6824-DK
• Description: BOARD EVALUATION FOR ATA6824
• Manufacturer: Atmel

Specifications of ATA6824-DK

• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6824
• Primary Attributes: Brush DC Motors, 5V, Watchdog, Voltage Regulator
• Secondary Attributes: Short-Circuit, Thermal & Undervoltage Protection
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

5.10
12
Short Circuit Detection
Atmel ATA6824
Figure 5-6.
The delays t
To detect a short in H-bridge circuitry, internal comparators detect the voltage difference
between source and drain of the external power NMOS. If the transistors are switched ON and
the source-drain voltage difference is higher than the value V
nosis pin DG1 will be set to ‘H’ and the drivers will be switched off. All gate driver outputs (Hx
and Lx) will be set to ‘L’. Releasing the gate driver outputs will set DG1 back to ‘L’. With the
next transition on the pin PWM, the corresponding drivers, depending on the DIR pin, will be
switched on again.
There is a PBAT supervision block implemented to detect the possible voltage drop on PBAT
during a short circuit. If the voltage at PBAT falls under V
off and DG1 will be set to “H”. It will be cleared as soon as the PBAT undervoltage condition
disappears.
The detection of drain source voltage exceedances is activated after the short circuit blanking
time t
PWM or
DIR
Lx
Hx
SC
, the short circuit detection of PBAT failures operates immediately.
HxLH
Timing of the Drivers
and t
t
LxHL
LxLH
t
CC
t
HxLH
include the cross conduction time t
t
Lxf
50%
t
Hxr
80%
20%
80%
20%
t
t
CC
HxHL
t
LxLH
PBAT_OK
t
Hxf
CC
SC
.
(4V with tolerances) the diag-
the drivers will be switched
t
Lxr
4931L–AUTO–02/11
t
t
t