ATMEGA32-16AU Atmel, ATMEGA32-16AU Datasheet - Page 42

• Manufacturer Part Number: ATMEGA32-16AU
• Description: IC AVR MCU 32K 16MHZ 5V 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32-16AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Processor Series: ATMEGA32x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: 2-Wire/SPI/USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Controller Family/series: AVR MEGA
• No. Of I/o's: 32
• Eeprom Memory Size: 1KB
• Ram Memory Size: 2KB
• Cpu Speed: 16MHz
• No. Of Timers: 3
• Rohs Compliant: Yes
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Total Internal Ram Size: 2KB
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: TQFP
• For Use With: ATSTK524 - KIT STARTER ATMEGA32M1/MEGA32C1ATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFPATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Watchdog Timer
Control Register –
WDTCR
2503Q–AVR–02/11
• Bits [7:5] – Reserved Bits
These bits are reserved bits in the ATmega32 and will always read as zero.
• Bit 4 – WDTOE: Watchdog Turn-off Enable
This bit must be set when the WDE bit is written to logic zero. Otherwise, the Watchdog will not
be disabled. Once written to one, hardware will clear this bit after four clock cycles. Refer to the
description of the WDE bit for a Watchdog disable procedure.
• Bit 3 – WDE: Watchdog Enable
When the WDE is written to logic one, the Watchdog Timer is enabled, and if the WDE is written
to logic zero, the Watchdog Timer function is disabled. WDE can only be cleared if the WDTOE
bit has logic level one. To disable an enabled Watchdog Timer, the following procedure must be
followed:
1. In the same operation, write a logic one to WDTOE and WDE. A logic one must be writ-
2. Within the next four clock cycles, write a logic 0 to WDE. This disables the Watchdog.
• Bits [2:0] – WDP2, WDP1, WDP0: Watchdog Timer Prescaler 2, 1, and 0
The WDP2, WDP1, and WDP0 bits determine the Watchdog Timer prescaling when the Watch-
dog Timer is enabled. The different prescaling values and their corresponding Timeout Periods
are shown in
Table 17. Watchdog Timer Prescale Select
Bit
Read/Write
Initial Value
WDP2
0
0
0
0
1
1
1
1
ten to WDE even though it is set to one before the disable operation starts.
WDP1
0
0
1
1
0
0
1
1
Table
R
7
–
0
WDP0
17.
0
1
0
1
0
1
0
1
R
6
–
0
1,024K (1,048,576)
2,048K (2,097,152)
Oscillator Cycles
Number of WDT
128K (131,072)
256K (262,144)
512K (524,288)
16K (16,384)
32K (32,768)
64K (65,536)
R
5
–
0
WDTOE
R/W
4
0
WDE
R/W
3
0
Typical Time-out
at V
WDP2
17.1ms
34.3ms
68.5ms
R/W
CC
0.14s
0.27s
0.55s
2
0
1.1s
2.2s
= 3.0V
WDP1
R/W
1
0
Typical Time-out
ATmega32(L)
WDP0
at V
R/W
0
0
16.3ms
32.5ms
0.13 s
65ms
0.26s
0.52s
CC
1.0s
2.1s
= 5.0V
WDTCR
42