ATAB5757 Atmel, ATAB5757 Datasheet - Page 6

• Manufacturer Part Number: ATAB5757
• Description: BOARD DEMO RF TRANSMITTER 433MHZ
• Manufacturer: Atmel
• Series: Smart RFr
• Type: Transmitterr

Specifications of ATAB5757

• Frequency: 433MHz
• Wireless Frequency: 433 MHz
• Modulation: ASK, FSK
• For Use With/related Products: ATA5757 @ 433MHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

4.1
4.1.1
4.1.2
6
Transmission with ENABLE = open
ATA5756/ATA5757
ASK Mode
FSK Mode
The ATA5756/ATA5757 is activated by ENABLE = open, FSK = High, ASK = Low. The microcon-
troller is then switched to external clocking. After typically 0.6 ms, the CLK driver is activated
automatically (i.e., the microcontroller waits until the XTO and CLK are ready). After another
time period of
modulated by means of pin ASK. After transmission, ASK is switched to Low and the microcon-
troller returns back to internal clocking. Then, the ATA5756/ATA5757 is switched to power-down
mode with FSK = Low.
Figure 4-1.
The ATA5756/ATA5757 is activated by FSK = High, ASK = Low. The microcontroller is then
switched to external clocking. After typically 0.6 ms, the CLK driver is activated automatically
(i.e., the microcontroller waits until the XTO and CLK are ready. After another time period of
≤
ASK = H. The ATA5756/ATA5757 is then ready for FSK modulation. The microcontroller starts to
switch on and off the capacitor between the crystal load capacitor and GND by means of pin
FSK, thus, changing the reference frequency of the PLL. IF FSK = L the output frequency is
lower, if FSK = H output frequency is higher. After transmission, FSK stays High and ASK is
switched to Low and the microcontroller returns back to internal clocking. Then, the
ATA5756/ATA5757 is switched to power-down mode with FSK = Low.
Figure 4-2.
250 µs, the PLL is locked and ready to transmit. The power amplifier is switched on with
ASK
FSK
CLK
FSK
ASK
CLK
≤
Timing ASK Mode with ENABLE not Connected to the Microcontroller
Timing FSK Mode with ENABLE not Connected to the Microcontroller
Power-down
250 µs, the PLL is locked and ready to transmit. The output power can then be
Power-down
ΔT
ΔT
XTO
Power-up,
XTO
Power-up,
PA off
PA off
> 250 µs
> 250 µs
(f
Power-up,
Power-up,
RF
PA on
PA on
(High)
= High)
(f
Power-up,
Power-up,
RF
PA off
PA off
(Low)
= Low)
Power-down
Power-down
4702J–RKE–09/08