TDA5250 Infineon Technologies, TDA5250 Datasheet - Page 71

• Manufacturer Part Number: TDA5250
• Description: TX/RX ASK/FSK 868-870MHZ 38TSSOP
• Manufacturer: Infineon Technologies
• Type: Transceiverr

Specifications of TDA5250

• Package / Case: 38-TSSOP
• Frequency: 868MHz
• Data Rate - Maximum: 64kbps
• Modulation Or Protocol: ASK, FSK
• Applications: RKE, Remote Control Systems
• Power - Output: 9dBm
• Sensitivity: -109dBm
• Voltage - Supply: 2.1 V ~ 5.5 V
• Current - Receiving: 9mA
• Current - Transmitting: 12mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Operating Frequency: 870 MHz
• Operating Supply Voltage: 2.5 V, 3.3 V, 5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 4.4mm
• Product Length (mm): 9.7mm
• Operating Supply Voltage (min): 2.1V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant
• Other names: SP000012956; TDA5250; TDA5250INTR; TDA5250XT; TDA5250XT

This yields the following results:
which have to be programmed into the D0 to D11 bits of the COUNT_TH1 and COUNT_TH2
registers (subaddresses 06H and 07H), respectively.
Default values (window counter inactive):
TH1= 000000000000
TH2= 000000000001
Note: The timing window of +-10% of a given high time T in general does not correspond to a
frequency window +-10% of the calculated data frequency.
3.7.2
The RF input power level is corresponding to a certain RSSI voltage, which can be seen in Section
3.5. The threshold TH3 of this RSSI voltage can be calculated with the following formula:
As an example a desired RSSI threshold voltage of 500mV results in TH3~26=011010 b , which has
to be written into D0 to D5 of the RSSI_TH3 register (sub address 08H).
Default value (RSSI detection inactive):
TH3=111111 b
3.8
ON= (2
OFF=( 2
f
Example: t
ON= 65535-(32300*0,005) ~ 65373= 1111111101011101
OFF= 65535-(32300*0,055) ~ 63758= 1111100100001110
The values have to be written into the D0 to D15 bits of the ON_TIME and OFF_TIME registers
(subaddresses 04H and 05H).
Data Sheet
RC
= Frequency of internal RC Oszillator
16
16
-1)-(f
-1)-(f
ON
RSSI threshold voltage - RF input power
Calculation of ON_TIME and OFF_TIME
= 0,005s, t
RC
RC
TH3
*t
*t
ON
OFF
=
)
b
b
desired
)
OFF
= 0,055s, f
TH1~ 1017= 001111111001
TH2~ 1243= 010011011011
RSSI
1.2V
threshold
RC
= 32300Hz
voltage
71
⋅
(
2
6
b
b
b
−
b
) 1
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TDA5250 D2
Version 1.7
Application
2007-02-26