cv110-1a WJ Communications, Inc., cv110-1a Datasheet - Page 2

• Manufacturer Part Number: cv110-1a
• Description: Cellular-band High Linearity Downconverter
• Manufacturer: WJ Communications, Inc.

CV110-1A: The application circuit can be broken up into four main
functions as denoted in the colored dotted areas above: RF/IF diplexing
(purple), amplifier matching (green), filtering (red), and dc biasing
(blue). There are various placeholders for chip components in the circuit
schematic so that a common PCB can be used for all WJ single-branch
converters. Additional placeholders for other optional functions such as
filtering are also included.
RF / IF Amplifier Matching:
matching element for optimal gain and input return loss performance.
The IF amplifier requires matching elements to optimize the
performance of the amplifier to the desired IF center frequency. Since
IF bandwidths are typically on the order of 5 to 10%, a simple two
element matching network, in the form of either a high-pass or low-pass
filter structure, is sufficient to match the MMIC IF amplifier over these
narrow bandwidths.
frequencies
[e-mail].
RF Bandpass Filtering:
the image frequencies and achieve the best noise figure performance
WJ Communications, Inc • Phone 1-800-WJ1-4401 • FAX: [phone] • e-mail: [e-mail] • Web site: www.wj.com , www.TriQuint.com
IF THRU
RF OUT
RF/IF
GND
GND
GND
N/C
1
2
3
4
5
6
7
RF/IF
RF Amp
RF Bandpass Filter /
28
8
Attenuator Pad
CV110-1A
Cellular-band High Linearity Downconverter
IF Feedthru
27
9
can
Path
(used for cellular versions only)
26
10
Device Architecture / Application Circuit Information
25
11
Proper component values for other IF center
RF / IF Diplexer
LO
RF Amp Bias
be
24
12
LO Driver Amp
Bandpass filtering is recommended to reject
23
13
IF Amp
provided
22
14
The RF amplifier requires a shunt
RF Amp Matching
21
20
19
18
17
16
15
IF OUT
GND
N/C
GND
BIAS
GND
LO IN
Frequency (MHz)
R8 (ohms)
C17 (pF)
L7 (nH)
L4 (nH)
by
MMIC Mixer
RF Amplifier
IF Amplifier
CV110-1A
RF Filter
IF Amp Matching
Stage
emailing
IF Amplifier Matching
LO Amp Bias
470
470
4.7
40
24
Gain
(dB)
13.5
-9.0
19.0
-1.5
IF Amp Bias
Typical Downconverter Performance Chain Analysis
Cumulative Performance
to
LO Amp Bias
430
240
4.7
50
15
Output
(dBm)
P1dB
21
---
22
with the downconverter. The bandpass filter, implemented with a SAW
filter on the application circuit, allows for the suppression of noise from
the image frequency. It is permissible to not use a filter and use a 2 dB
pad with R6, R7, and R16 instead with slightly degraded noise figure
performance. Standard WJ evaluation boards will have the 2 dB pad in
place.
External Diplexer:
signal impinges on the switching elements of the mixer; the interaction
with these switches produces a signal at the IF frequency. The two
signals (RF and IF) are directed to the appropriate ports by the external
diplexer. A four-element diplexer is used in the circuit implementation
(L8 and C2 are not used). Pin 5 contains the IF signal and allows the
signal to be transferred to pin 25 for the convenience of PCB layouts.
DC biasing:
amplifiers in the converter. R1 sets the operating current for the last
stage of the LO amplifier and is chosen to optimize the mixer LO drive
level. Proper RF chokes and bypass capacitors are chosen for proper
amplifier biasing at the intended frequency of operation. The “+5 V” dc
bias should be supplied directly from a voltage regulator.
8
150
330
3.3
75
22
Output
(dBm)
40.0
23.0
39.1
IP3
---
100
150
330
2.2
10
Printed Circuit Board Material:
.014” FR-4, 4 layers, .062” total thickness
DC bias must be provided for the RF, LO and IF
(dB)
NF
3.5
1.5
9.8
2.5
125
120
330
8.2
2.2
Specifications and information are subject to change without notice
In a downconversion application, the incoming RF
Current
130
120
330
(mA)
6.8
2.2
150
150
360
60
---
Gain
(dB)
22.0
22.0
13.5
12.0
3.0
Cumulative Performance
Output
(dBm)
P1dB
21.0
20.3
20.3
19.5
6.1
Page 2 of 4 April 2007
Output
(dBm)
40.0
38.5
22.1
37.0
37.0
IP3
(dB)
NF
3.5
3.5
4.5
5.0
5.0