ATMEGA163L-4AC Atmel, ATMEGA163L-4AC Datasheet - Page 29

• Manufacturer Part Number: ATMEGA163L-4AC
• Description: IC AVR MCU 16K A/D 2.7V 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA163L-4AC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Internal Voltage Reference
Voltage Reference Enable
Signals and Start-up Time
Interrupt Handling
1142E–AVR–02/03
• Bit 2 – BORF: Brown-out Reset Flag
This bit is set if a Brown-out Reset occurs. The bit is reset by a Power-on Reset, or by
writing a logic zero to the Flag.
• Bit 1 – EXTRF: External Reset Flag
This bit is set if an External Reset occurs. The bit is reset by a Power-on Reset, or by
writing a logic zero to the flag.
• Bit 0 – PORF: Power-on Reset Flag
This bit is set if a Power-on Reset occurs. The bit is reset only by writing a logic zero to
the flag.
To make use of the Reset Flags to identify a reset condition, the user should read and
then reset the MCUSR as early as possible in the program. If the register is cleared
before another reset occurs, the source of the reset can be found by examining the
Reset Flags.
ATmega163 features an internal bandgap reference with a nominal voltage of 1.22V.
This reference is used for Brown-out Detection, and it can be used as an input to the
Analog Comparator and ADC. The 2.56V reference to the ADC is also generated from
the internal bandgap reference.
To save power, the reference is not always turned on. The reference is on during the fol-
lowing situations:
1. When the BOD is enabled (by programming the BODEN Fuse)
2. When the bandgap reference is connected to the Analog Comparator (by setting
3. When the ADC is enabled.
Thus, when the BOD is not enabled, after setting the ACBG bit, the user must always
allow the reference to start up before the output from the Analog Comparator is used.
The bandgap reference uses typically 10 µA, and to reduce power consumption in
Power-down mode, the user can avoid the three conditions above to ensure that the ref-
erence is turned off before entering Power-down mode.
The ATmega163 has two 8-bit Interrupt Mask Control Registers: GIMSK – General
Interrupt Mask Register and TIMSK – Timer/Counter Interrupt Mask Register.
When an interrupt occurs, the Global Interrupt Enable I-bit is cleared (zero) and all inter-
rupts are disabled. The user software must set (one) the I-bit to enable nested
interrupts. The I-bit is set (one) when a Return from Interrupt instruction – RETI – is
executed.
When the Program Counter is vectored to the actual Interrupt Vector in order to execute
the interrupt handling routine, hardware clears the corresponding flag that generated the
interrupt. Some of the interrupt flags can also be cleared by writing a logic one to the flag
bit position(s) to be cleared.
If an interrupt condition occurs when the corresponding interrupt enable bit is cleared
(zero), the Interrupt Flag will be set and remembered until the interrupt is enabled, or the
flag is cleared by software.
the ACBG bit in ACSR).
ATmega163(L)
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