ATmega1284RZAP Atmel Corporation, ATmega1284RZAP Datasheet - Page 32

• Manufacturer Part Number: ATmega1284RZAP
• Manufacturer: Atmel Corporation

Specifications of ATmega1284RZAP

• Flash (kbytes): 128 Kbytes
• Max. Operating Frequency: 20 MHz
• Max I/o Pins: 32
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Crypto Engine: No
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Operating Voltage (vcc): 1.8 to 3.6
• Timers: 3
• Frequency Band: 2.4 GHz
• Max Data Rate (mb/s): 0.25
• Antenna Diversity: No
• External Pa Control: No
• Power Output (dbm): 3
• Receiver Sensitivity (dbm): -101
• Receive Current Consumption (ma): 16.0
• Transmit Current Consumption (ma): 17.0
• Link Budget (dbm): 104

7.5
8059D–AVR–11/09
Low Frequency Crystal Oscillator
Table 7-6.
Notes:
The Low-frequency Crystal Oscillator is optimized for use with a 32.768 kHz watch crystal.
When selecting crystals, load capasitance and crystal’s Equivalent Series Resistance, ESR
must be taken into consideration. Both values are specified by the crystal vendor.
ATmega1284P oscillator is optimized for very low power consumption, and thus when selecting
crystals, see
crystals
Table 7-7.
Note:
The Low-frequency Crystal Oscillator provides an internal load capacitance, see
page 32
Table 7-8.
The capacitance (Ce + Ci) needed at each TOSC pin can be calculated by using:
Oscillator Source /
Power Conditions
Ceramic resonator, fast
rising power
Ceramic resonator, slowly
rising power
Crystal Oscillator, BOD
enabled
Crystal Oscillator, fast
rising power
Crystal Oscillator, slowly
rising power
ATmega1284P
1. These options should only be used when not operating close to the maximum frequency of the
2. These options are intended for use with ceramic resonators and will ensure frequency stability
1. Maximum ESR is typical value based on characterization
at each TOSC pin.
Device
device, and only if frequency stability at start-up is not important for the application. These
options are not suitable for crystals.
at start-up. They can also be used with crystals when not operating close to the maximum fre-
quency of the device, and if frequency stability at start-up is not important for the application.
Table 7-7 on page 32
Start-up Times for the Full Swing Crystal Oscillator Clock Selection
Maximum ESR Recommendation for 32.768 kHz Watch Crystal
Capacitance for Low-frequency Crystal Oscillator
Crystal CL (pF)
12.5
9.0
Start-up Time from
Power-down and
32kHz Osc. Type
Power-save
System Osc.
Timer Osc.
16K CK
16K CK
16K CK
1K CK
1K CK
for maximum ESR recommendations on 9 pF and 12.5 pF
Ce
+
Ci
=
2 CL
⋅
Additional Delay
Cap(Xtal1/Tosc1)
–
14CK + 4.1 ms
14CK + 65 ms
14CK + 4.1 ms
14CK + 65 ms
C
(V
from Reset
s
CC
14CK
18 pF
6 pF
= 5.0V)
Max ESR [kΩ]
(2)
(2)
ATmega1284P
65
30
CKSEL0
Cap(Xtal2/Tosc2)
(1)
0
1
1
1
1
8 pF
6 pF
Table 7-8 on
SUT1..0
11
00
01
10
11
32