ATA6834-DK Atmel, ATA6834-DK Datasheet - Page 9

• Manufacturer Part Number: ATA6834-DK
• Description: BOARD BLDC MOTOR CTRL ATA6833/34
• Manufacturer: Atmel
• Type: MOSFET & Power Driverr

Specifications of ATA6834-DK

• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6833 / ATA6834, ATmega32M1
• Primary Attributes: 3-Ph BLDC, IC with FET Driver, LIN Transceiver, Volt Regulator, Watchdog
• Secondary Attributes: LCD with Touch Screen on MCU Controller Board
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6. High Ambient Temperature
9143C–AUTO–03/10
The ATmega32M1 is available in automotive temperature range according to AEC-Q100 up to
grade 0. This allows operating temperature up to 150°C.
The maximum junction temperature of the ATA6834 is 200°C. Therefore for 150°C ambient
temperature applications a margin of 50K for power dissipation is available. Basically there are
three heat sources in the ATA6833: VCC voltage regulator, charge pump and all the rest of
internal operating circuitry.
Example: 100 nC gate charge capacity, 20 kHz PWM frequency, only one half bridge is
switched once, high side gate source voltage = low side gate source voltage = 15V
P
P
Total power dissipation is P
The SBC ATA6833 has enhanced temperature monitoring. A first temperature threshold 5K
lower than maximum specified junction temperature indicates at pin DG3 a temperature pre-
warning. If the junction temperature is increased by further 25K, the outputs, voltage regulator
and LIN transceiver are switched off. Maximum junction temperature of the ATA6833 is 150°C
and of the ATA6834 is 200°C. The maximum ambient temperature depends on the power dis-
sipation of the device; a better thermal contact allows a higher ambient temperature.
For exact behavior please see the ATA6833/ATA6834 datasheet on the Atmel website.
PBAT
CP
BLDC Motor Control Kit with ATA6833/ATA6834
1. The VCC voltage regulator is the main heating source on the device. Typical VCC
2. The current consumption of the internal operating circuitry is specified in the
3. The power dissipation of the charge pump depends on the dedicated n-channel out-
= 3
regulator parameters are 5V VCC output voltage, 30 mA VCC output current and 15V
VBAT supply voltage. Based on these parameters, the thermal energy to dissipate is
P
datasheet as maximum 7 mA. At VBAT = 15V the power dissipation is
P
put MOSFETs and the PWM frequency. Due to the design of the charge pump,
approximately the triple charge is needed into VBAT to charge the gates of the exter-
nal MOSFETs. The ATA6833 needs to dissipate the complete power absorbed
through PBAT - inside the charge pump, the on and off switches. The gates of the
external MOSFETs are considered as ideal capacitors.
= 3
VCC
INTERNAL
15V
= (U
U
GS
VBAT
= U
100 nC
I
VBAT
GATE
– U
VCC
= 3
I
VBAT
)
20 kHz = 3
TOTAL
I
U
VCC
= 15V
GS
= P
= (15V – 5V)
VCC
Q
GATE
7 mA = 105 mW.
+ P
15V
PBAT
f
PWM
2 mA = 90 mW
+ P
30 mA = 300 mW.
INTERNAL
= 495 mW
(3)
(4)
(1)
(2)
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