MRF24J40-I/ML Microchip Technology, MRF24J40-I/ML Datasheet - Page 98

• Manufacturer Part Number: MRF24J40-I/ML
• Description: IC TXRX IEEE/ZIGBEE 2.4GHZ 40QFN
• Manufacturer: Microchip Technology

Specifications of MRF24J40-I/ML

• Package / Case: 40-QFN
• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: ISM, ZigBee™
• Power - Output: 0dBm
• Sensitivity: -95dBm
• Voltage - Supply: 2.4 V ~ 3.6 V
• Current - Receiving: 18mA
• Current - Transmitting: 18mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Number Of Receivers: 1
• Number Of Transmitters: 1
• Wireless Frequency: 2.4 GHz
• Interface Type: 4 Wire SPI
• Noise Figure: 8 dB
• Output Power: + 0 dBm
• Operating Supply Voltage: 2.5 V, 3.3 V
• Maximum Operating Temperature: 85 C
• Mounting Style: SMD/SMT
• Maximum Supply Current: 22 mA
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

3.8.1.1
The superframe structure is shown in Figure 3-4. A
superframe is bounded by the transmission of a
beacon frame and can have an active and inactive
portion. The coordinator will interact with its PAN only
during the active portion of the superframe, and during
the inactive portion of the superframe, the coordinator
can go to a low-power mode. The active portion of the
superframe is divided into 16 equally spaced slots and
is composed of three parts: a beacon, a Contention
Access Period (CAP) and an optional Contention Free
Period (CFP). The structure of the superframe depends
FIGURE 3-4:
DS39776C-page 98
MRF24J40
Beacon
SD
BI
Backoff Period (aUnitBackoffPeriod = 20 symbols)
0
0
Superframe Duration (SD) = aBaseSuperframeDuration * 2
1
1
Superframe Structure
2
2
3
3
CAP
SUPERFRAME STRUCTURE
4
4
5
5
(SO – ORDER 0x10<3:0>)
Slot
Active Portion
6
6
7
7
Beacon Interval (BI) = aBaseSuperframeDuration * 2
8
8
CAP End Slot = ESLOTG1 (0x13<3:0>)
9 10 11 12 13 14 15
GTS1
CFP
G
T
S
(BO – ORDER 0x10<7:4>)
2
Preliminary
GTS End Slots = ESLOTG23 (0x1E),
ESLOTG45 (0x1F), ESLOT67 (0x20)
SO
symbols
GTS3
on the values of Beacon Order (BO) and Superframe
Order (SO). The CFP, if present, follows immediately
after the CAP and extends to the end of active portion
of the superframe. Any allocated GTSs shall be located
in the CFP of the active portion of the superframe.
All the frames transmitted in the CAP, except
Acknowledgement frames and data frames that imme-
diately follow the data request command, must use
slotted CSMA-CA. Refer to Section 3.9 “Carrier
Sense
(CSMA-CA) Algorithm” for more information.
Multiple
BO
symbols
Inactive Portion
Inactive Portion
Access-Collision
© 2010 Microchip Technology Inc.
Avoidance
Beacon