T5760-TGQ Atmel, T5760-TGQ Datasheet - Page 19

• Manufacturer Part Number: T5760-TGQ
• Description: IC RX 868MHZ ISM ASK/FSK 20-SOIC
• Manufacturer: Atmel

Specifications of T5760-TGQ

• Frequency: 868MHz
• Sensitivity: -110dBm
• Data Rate - Maximum: 10 kBaud
• Modulation Or Protocol: ASK, FSK
• Applications: General Purpose Data Transmission Systems
• Current - Receiving: 7.8mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 20-SOIC (0.300", 7.50mm Width)
• Operating Temperature (min): -40C
• Operating Temperature (max): 105C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Memory Size: -
• Lead Free Status / Rohs Status: Not Compliant
• Other names: T5760-TGQTR

Digital Noise
Suppression
Automatic Noise
Suppression
Figure 26. Output of Digital Noise at the End of the Data Stream
Figure 27. Automatic Noise Suppression
Figure 28. Occurrence of a Pulse at the End of the Data Stream
4561B–RKE–10/02
Data_out (DATA)
DATA_CLK
Data_out (DATA)
DATA_CLK
Dem_out
Data_out (DATA)
DATA_CLK
Bit-check
Bit-check
mode
mode
Bit check ok
Bit check ok
Preburst
Preburst
Receiving mode,
data clock control
logic active
Receiving mode,
data clock control
logic active
After a data transmission, digital noise appears on the data output (see Figure 26). Pre-
venting that digital noise keeps the connected microcontroller busy. It can be
suppressed in two different ways.
If the bit Noise_Disable (Table 9) in the OPMODE register is set to 1 (default), the
receiver changes to bit-check mode at the end of a valid data stream. The digital noise
is suppressed and the level at Pin DATA is High in that case. The receiver changes
back to receiving mode, if the bit check was successful.
This way to suppress the noise is recommended if the data stream is Manchester or
Bi-phase coded and is active after power on.
Figure 28 illustrates the behavior of the data output at the end of a data stream. Note
that if the last period of the data stream is a high period (rising edge to falling edge), a
pulse occurs on Pin DATA. The length of the pulse depends on the selected baud-rate
range.
'1'
Receiving mode,
data clock control
logic active
Data stream
Data
Data
Timing error
'1'
Digital Noise
'1'
(t
ee
Receiving mode,
bit check aktive
< T
Lim_min
T
Bit-check
ee
mode
OR T
Lim_max
Digital Noise
< t
T
ee
Pulse
< T
Bit check ok
Bit check ok
Lim_min_2T
OR t
Preburst
Preburst
Digital noise
ee
Receiving mode,
data clock control
logic active
> T
Bit-check mode
Receiving mode,
data clock control
logic active
Lim_max2T
Data
Data
Receiving mode,
bit check aktive
T5760/T5761
Digital Noise
Bit-check
mode
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