ATA6613-EK Atmel, ATA6613-EK Datasheet - Page 18

• Manufacturer Part Number: ATA6613-EK
• Description: BOARD DEMO LIN-MCM FOR ATA6613
• Manufacturer: Atmel

Specifications of ATA6613-EK

• Main Purpose: Interface, LIN + MCU
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6613
• Primary Attributes: LIN-SBC (System-Basis-Chip) Transceiver, LIN 2.0, Voltage Regulator, Window Watchdog
• Secondary Attributes: 16 kB Flash, 4 Power Modes: Pre-Normal, Normal, Sleep, Silent, 48-QFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6. Boosting Up the Voltage Regulator
For some applications there is a requirement for a higher current than the internal voltage reg-
ulator can deliver (50 mA). In order to meet this requirement, it is possible to boost up the
maximum current by using an external NPN transistor. A transistor, MJD31C in a D-PAK pack-
age, is already mounted on the development board, and in addition to the transistor there are
two more components placed on the development board, the resistor R9 (3.3 ) and the elec-
trolytic capacitor C3 (2.2 µF). In addition, the jumper boost has to be removed when using the
external transistor.
Note that the output voltage is no longer short-circuit protected when boosting up the output
current with an external NPN transistor.
The limiting parameter for the currently available output current is the maximum power dissi-
pation of the external NPN transistor. In the version at this stage, the thermal resistance of the
MJD31C soldered on the minimum pad size is 80 K/W. This means that the possible maxi-
mum output current in the case of V
= 12V is approximately 230 mA at room temperature. It
S
is not recommended to exceed this limit as the transistor could be damaged as a result of
overtemperature. If a higher output current is required, additional cooling of the external tran-
sistor has to be ensured.
ATA6612/ATA6613
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9127A–AUTO–05/08