Filename: tfs 246m.doc

Version 1.6

20.04.2005

Filter specification

TFS 246M

1/5

Tele Filter GmbH

Potsdamer Straße 18

D 14 513 TELTOW / Germany

Tel: (+49) 3328 4784-0 / Fax: (+49) 3328 4784-30

E-Mail:

tft@telefilter.com

Measurement condition

Ambient temperature:

23

°C

Input power level:

0

dBm

Terminating impedance: *

Input:

690 Ω || -3,2 pF

Output:

690 Ω || -3,2 pF

External Coil:

100 nH

Characteristics

Remark:

Reference level for the relative attenuation arel of the TFS 246 M is the minimum of the pass band attenuation amin. The minimum of the pass band

attenuation amin is defined as the insertion loss ae. The centre frequency fc is the arithmetic mean value of the upper and lower frequencies at the 3 dB

filter attenuation level relative to the insertion loss ae. The nominal frequency fN is fixed on 246 MHz without tolerance. The given values for the relative

attenuation arel and for the group delay have to be reached at the frequencies given below even if the centre frequency fc is shifted due to the temperature

coefficient of frequency TCf in the operating temperature range and due to a production tolerance for the centre frequency fc.

D a t a

typ. value

tolerance / limit

Insertion loss

ae=amin

3,9

dB

max.

5

dB

Nominal frequency

-

246

MHz

Center frequency

246,01

MHz

-

Amplitude ripple

85

kHz

93

kHz

0,4

dB

max.

1,5

dB

Relative attenuation

arel

120

kHz

1

dB

max.

3

dB

330

kHz

400

kHz

26

dB

min.

18

dB

400

kHz

600

kHz

36

dB

min.

25

dB

600

kHz

800

kHz

48

dB

min.

40

dB

800

kHz

1,6

MHz

49

dB

min.

45

dB

1,6

20

MHz

51

dB

min.

46

dB

20

100

MHz

61

dB

min.

50

dB

1,6

3

MHz

50

dB

min.

45

dB

3

26

MHz

50

dB

min.

46

dB

26

46

MHz

44

dB

min.

40

dB

46

100

MHz

56

dB

min.

50

dB

Group delay ripple

50

kHz

0,35

µs

max.

1,2

µs

70

kHz

0,5

µs

max.

1,5

µs

100

kHz

0,85

µs

max.

2,5

µs

Operating temperature range

OTR

-

- 20 °C ... + 70 °C

Storage temperature range

-

- 30 °C ... + 85 °C

Frequency inversion temperature

25

°C

-

Temperature coefficient of frequency

TCf **

-0,036

ppm/K²

-

*) The terminating impedances depend on parasitics and q-values of matching elements and the board used, and are to be understood as reference values

only. Should there be additional questions do not hesitate to ask for an application note or contact our design team.

**)

Generated:

Checked / Approved:

VI TELEFILTER reserves the right to make changes to the product(s) and/or information contained herein without notice. No liability is

assumed as a result of their use or application. No rights under any patent accompany the sale of any such product(s) or information.