ATMEGA8HVD-4MX Atmel, ATMEGA8HVD-4MX Datasheet - Page 104

• Manufacturer Part Number: ATMEGA8HVD-4MX
• Description: MCU AVR 8K FLASH 2.1-8V 4MHZ QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8HVD-4MX

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 2.4 V
• Data Converters: A/D 1x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 18-MLF® Exposed Pad (Staggered Leads), DFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Connectivity: -

20. Battery Protection
20.1
20.2
Table 20-1.
104
Battery Protection Type
Short-circuit Protection
Discharge Over-current
Protection
Charge Over-current
Protection
External Protection Input
Features
Overview
ATmega4HVD/8HVD
Effect of Battery Protection Types
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•
•
•
•
•
The Current Battery Protection circuitry (CBP) monitors the charge and discharge current and
disables C-FET and D-FET if a Short-circuit, Over-current or High-current condition is
detected. There are three different programmable detection levels: Short-circuit Detection
Level, Discharge Over-current Detection Level, and Charge Over-current Detection Level.
There are two different programmable delays for activating Current Battery Protection: Short-
circuit Reaction Time and Over-current Reaction Time. After Current Battery Protection has
been activated, the application software must re-enable the FETs. The Battery Protection
hardware provides a hold-off time of 1 second nominally before software can re-enable the
discharge FET. This provides safety in case the application software should unintentionally re-
enable the discharge FET too early.
The activation of a protection also issues an interrupt to the CPU. The battery protection inter-
rupts can be individually enabled and disabled by the CPU.
In addition, the module offers an External Protection Input. The activation of the External Pro-
tection Input operates independently of the rest of the battery protection mechanisms. The
activation/deactivation of this protection is instantaneously controlled from the External Protec-
tion Input port, and will not deactivate or affect the other battery protection mechanisms.
The effect of the various battery protection types is given in
In order to reduce power consumption, Short-circuit and Discharge Over-current Protection
are automatically deactivated when the D-FET is disabled. The Charge Over-current is dis-
abled when the C-FET is disabled. Note that Charge Over-current Protection is never
automatically disabled when the chip is operated in DUVR mode. Also note that none of the
current protections are deactivated by External Protection Input. To save power during an
External Protection event, DFE and CFE should be cleared in the FCSR register. Make also
sure that the chip is not operated in DUVR mode.
Short-circuit Protection
Discharge Over-current Protection
Charge Over-current Protection
External Protection Input
Programmable and Lockable Detection Levels and Reaction Times
Autonomous Operation Independent of CPU
Interrupt Requests
Entry and/or Exit
Entry
Entry
Entry
Disabled
Disabled
Disabled
Disabled
C-FET
Disabled
Disabled
Disabled
Disabled
D-FET
Table
20-1.
Operational
Operational
Operational
Operational
MCU
8052B–AVR–09/08