ATR2406-PNQG Atmel, ATR2406-PNQG Datasheet - Page 20

• Manufacturer Part Number: ATR2406-PNQG
• Manufacturer: Atmel

Specifications of ATR2406-PNQG

• Operating Temperature Classification: Commercial
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.6V
• Lead Free Status / Rohs Status: Compliant

10. Appendix: Current Calculations for a Remote Control
20
ATR2406
Assumptions:
Protocol:
Channel:
Loop filter:
Handheld device:
Base station device: The base station will periodically scan all the channels of the used
Basic Numbers:
Peak current ATR2406 in TX at 1.152 Kbps:
Peak current ATR2406 in RX at 1.152 Kbps:
Peak current ATR2406 synthesizer running:
Current ATmega88 active:
Current ATmega88 power down (no WDT):
Current ATmega88 power down (+ WDT):
Loop settling time of ATR2406:
Configuration of ATR2406:
Time needed for exchanging a packet at 1.152 Kbps
Amount of current needed for transmitting one packet:
Q1 = (0.005A + 0.026A)
Q2 = (0.005A + 0.026A)
Q3 = (0.005A + 0.026A)
Q4 = (0.005A + 0.042A)
Q5 = (0.005A)
Q6 = (0.005A + 0.026A)
Q7 = (0.005A + 0.026A)
Q8 = (0.005A + 0.057A)
Q9 = (0.005A + 0.057A)
Q10 = (0.005A + 0.057A)
250 µs = 1.25 µAs (charge for turn around (TX to RX, RX to TX, etc.))
A data packet consists of 24 bytes.
24 Bytes = 240 bits (USART connection)
T
The system will use 5 predefined channels for Frequency Hopping
Spread Spectrum (FHSS) which give improved immunity against
interferers.
Loop filter settling time will be 110 µs
if not in use the handheld device will be in power down mode with the
AVR’s watchdog timer disabled. The AVR powerdown current is
typically 1.25 µA. If an external voltage regulator is used, additional
power down current has to be taken into calculation.
subset. The base station will stay on one chaneel for 2 seconds. If the
base station receives a correct packet an acknowledge will be returned
to the handheld device. The power consumption of the base station
device is not power sensitive as this part of the application is normally
mains powered.
packet_length
5030 µs= 155 µAs (charge up time ATR2406 + AVR internal
30 µs = 0.93 µAs (charge for configuring the ATR2406)
110 µs = 3.41 µAs (charge for settling the Loop Filter)
210 µs = 9.87 µAs (charge for transmitting the packet)
30 µs = 0.93 µAs (charge for configuring the ATR2406)
60 µs = 1.86 µAs (charge for settling the Loop Filter)
50 µs = 3.10 µAs (charge until valid data can be received)
210 µs = 13.02 µAs (charge for receiving the packet)
50 µs = 3.1 µAs (charge for latency before receiving)
= 210 µs at 1.152 Mbps
calculations)
42 mA
57 mA
26 mA
5 mA
1.25 µA
5 µA
110 µs
30 µs
210 µs
4779K–ISM–06/06