U3741BM-M3FL Atmel, U3741BM-M3FL Datasheet - Page 6

• Manufacturer Part Number: U3741BM-M3FL
• Description: RF Receiver UHF Remote Receiver IF BW of 600kHz
• Manufacturer: Atmel
• Type: RKE Design Kit (U2741B, U3741BM)r

Specifications of U3741BM-M3FL

• Package / Case: SOIC-20
• Operating Frequency: 450 MHz
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 3. Input Matching Network with SAW Filter
Figure 4. Input Matching Network without SAW Filter
6
RF
f
RF
IN
= 433.92 MHz
f
RF
RF
= 433.92 MHz
U3741BM
IN
8.2p
C2
22p
C3
15p
TOKO LL2012
3.3p
F33NJ
L2
33n
22n
L
25n
TOKO LL2012
1
2
25n
100p
IN
IN_GND
F22NJ
8
9
C16
100p
CASE_GND
Please note that for all coupling conditions (see Figure 3 and Figure 4), the bond wire
inductivity of the LNA ground is compensated. C3 forms a series resonance circuit
together with the bond wire. L = 25 nH is a feed inductor to establish a DC path. Its
value is not critical but must be large enough not to detune the series resonance circuit.
For cost reduction, this inductor can be easily printed on the PCB. This configuration
improves the sensitivity of the receiver by about 1 dB to 2 dB.
3, 4
LNAGND
LNA_IN
U3741BM
8
9
B3555
LNAGND
LNA_IN
U3741BM
27n
L3
7, 8
TOKO LL2012
OUT_GND
27NJ
C17
8.2p
OUT
5
6
f
RF
RF
= 315 MHz
IN
RF
f
RF
IN
= 315 MHz
33p
3.3p
10p
C2
47p
C3
39n
TOKO LL2012
F82NJ
TOKO LL2012
25n
L2
82n
100p
F39NJ
L
25n
1
2
IN
IN_GND
8
9
LNAGND
LNA_IN
U3741BM
8
9
100p
C16
CASE_GND
LNAGND
U3741BM
3, 4 7, 8
LNA_IN
B3551
47n
L3
TOKO LL2012
OUT_GND
F47NJ
C17
22p
4662B–RKE–10/04
OUT
5
6