ATMEGA128RFA1-ZU Atmel, ATMEGA128RFA1-ZU Datasheet - Page 82

• Manufacturer Part Number: ATMEGA128RFA1-ZU
• Description: IC AVR MCU 2.4GHZ XCEIVER 64QFN
• Manufacturer: Atmel
• Series: ATMEGAr

Specifications of ATMEGA128RFA1-ZU

• Frequency: 2.4GHz
• Data Rate - Maximum: 2Mbps
• Modulation Or Protocol: 802.15.4 Zigbee
• Applications: General Purpose
• Power - Output: 3.5dBm
• Sensitivity: -100dBm
• Voltage - Supply: 1.8 V ~ 3.6 V
• Current - Receiving: 12.5mA
• Current - Transmitting: 14.5mA
• Data Interface: PCB, Surface Mount
• Memory Size: 128kB Flash, 4kB EEPROM, 16kB RAM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VFQFN, Exposed Pad
• Rf Ic Case Style: QFN
• No. Of Pins: 64
• Supply Voltage Range: 1.8V To 3.6V
• Operating Temperature Range: -40°C To +85°C
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 128 KB
• Data Ram Size: 16 KB
• Interface Type: JTAG
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 38
• Number Of Timers: 6
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVR128RFA1-EK1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.6.6 Frequency Synthesizer (PLL)
9.6.6.1 Overview
9.6.6.2 RF Channel Selection
9.6.6.3 Frequency Agility
82
ATmega128RFA1
Figure 9-26. Setup for Using an External Frequency Reference
The main features of the phase-locked loop are:
• Generate RX/TX frequencies for all 2.4 GHz channels of IEEE 802.15.4;
• Autonomous calibration loops for stable operation within the operating range;
• Two PLL-interrupts for status indication;
• Fast PLL settling to support frequency hopping;
The PLL generates the RF frequencies for the radio transceiver. During receive
operation the frequency synthesizer works as a local oscillator for the receive frequency
of the radio transceiver. During transmit operation the voltage-controlled oscillator
(VCO) is directly modulated to generate the RF transmit signal. The frequency
synthesizer is implemented as a fractional-N PLL.
Two calibration loops ensure correct PLL functionality within the specified operating
limits.
The PLL is designed to support 16 channels in the 2.4 GHz ISM band with channel
spacing of 5 MHz according to IEEE 802.15.4. The center frequency of these channels
is defined as follows:
F
where k is the channel number.
The channel k is selected by the CHANNEL bits of register PHY_CC_CA.
When the PLL is enabled during state transition from TRX_OFF to PLL_ON the settling
time is typically t
(AVREG) and the PLL self calibration (refer to
? ? ? ? ? ? ? ? ?
Switching between 2.4 GHz ISM band channels in PLL_ON or RX_ON states is
typically done within t
frequency hopping applications.
The PLL frequency is changed to the transmit frequency within t
starting the transmit procedure and before starting the transmission. After the
transmission the PLL settles back to the receive frequency within t
frequency step does not generate a TRX24_PLL_LOCK or TRX24_PLL_UNLOCK
interrupt within these time spans.
c
= 2405 + 5 (k – 11) in [MHz], for k = 11, 12 ... 26
XTAL1
TR4
). A lock of the PLL is indicated with a TRX24_PLL_LOCK interrupt.
= 110 µs including the settling time of the analog voltage regulator
TR20
16 MHz
= 11 µs. This makes the radio transceiver highly suitable for
XTAL2
IC internal
Table 9-8 on page
PCB
42Table 9-8 and
8266A-MCU Wireless-12/09
TR23
TR24
= 16 µs after
= 32 µs. This
? ?