3 Mar 16, 2004
SAW Components B3765
315,50 MHzLow-loss Filter
Data Sheet
Characteristics
Reference temperature:
T
A
= –45 ... +95˚C
Terminating source impedance:
Z
S
= 50 Ω and matching network
Terminating load impedance:
Z
L
= 50 Ω and matching network
1)
Impedance for passband matching bases on an ideal, perfect matching of the SAW filter to
source- and to load impedance (here 50 Ohm). After the SAW filter is removed and input imped-
ance into the input matching / output matching network is calculated.
The conjugate complex value of these characteristic impedances are the input and output imped-
ances for flat passband. For more details, we refer to EPCOS application note #4.
min. typ. max.
Center frequency
f
C
— 315,50 — MHz
(center frequency between 3 dB points)
Minimum insertion attenuation α
min
(including losses in matching network)
315,35 ... 315,65 MHz — 1,9 2,9 dB
Pass band (relative to α
min
)
315,35 ... 315,65 MHz — 0,5 2,0 dB
315,32 ... 315,68 MHz — 0,7 3,0 dB
314,28 ... 315,72 MHz — 1,0 6,0 dB
Pass bandwidth
α
rel
≤ 3 dB 0,54 0,59 0,64 MHz
Relative attenuation (relative to α
min
) α
rel
10,00 ... 295,00 MHz 48 53 — dB
295,00 ... 305,00 MHz 45 50 — dB
305,00 ... 313,30 MHz 25 30 — dB
313,30 ... 313,70 MHz 33 40 — dB
313,70 ... 314,80 MHz 13 18 — dB
316,20 ... 323,50 MHz 13 17 — dB
323,50 ... 335,50 MHz 38 45 — dB
335,50 ... 600,00 MHz 43 48 — dB
600,00 ...1000,00 MHz 60 70 — dB
Impedance for pass band matching
1)
Input:
Z
IN
=
R
IN
||
C
IN
— 340 || 2,6 — Ω || pF
Output:
Z
OUT
=
R
OUT
||
C
OUT
—
340 || 2,6
— Ω || pF
