RFMD RF2459

RF2459
Preliminary
8
3V PCS DOWNCONVERTER
Typical Applications
• CDMA/TDMA/DCS1900 PCS Systems
• Micro-Cell PCS Base Stations
• PHS 1500/WLAN 2400 Systems
• Portable Battery-Powered Equipment
• General Purpose Downconverter
Product Description
0.006
+ 0.003
0.192
+ 0.008
The RF2459 is a monolithic integrated downconverter for
PCS, PHS, and WLAN applications. The IC contains all of
the required components to implement the RF functions
of the downconverter. It contains a double-balanced Gilbert cell mixer and a balanced IF output. The mixer’s high
third-order intercept point makes it ideal for digital cellular
applications. The IC is designed to operate from a single
3V power supply.
0.012
0.0256
0.118
+ 0.004 sq.
0.034
0.021
+ 0.004
Optimum Technology Matching® Applied
ü
Si Bi-CMOS
GaAs HBT
GaAs MESFET
SiGe HBT
Si CMOS
0.006
+ 0.002
NOTES:
1. Shaded lead is pin 1.
2. All dimensions are exclusive of
flash, protrusions or burrs.
3. Lead coplanarity: 0.002 with
respect to datum "A".
Package Style: MSOP-8
Features
• Extremely High Dynamic Range
• Single 3V Power Supply
• 1500MHz to 2500MHz Operation
LO IN
1
8
IF+
GND2
2
7
IF-
VCC
3
6
GND3
GND1
4
5
RF IN
Ordering Information
RF2459
RF2459 PCBA
Functional Block Diagram
Rev A2 010717
3V PCS Downconverter
Fully Assembled Evaluation Board
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
8
FRONT-ENDS
6° MAX
0° MIN
Si BJT
-A-
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
8-97
RF2459
Preliminary
Absolute Maximum Ratings
Parameter
Ratings
Unit
Supply Voltage
Input LO and RF Levels
Ambient Operating Temperature
Storage Temperature
-0.5 to 7.0
+6
-40 to +85
-40 to +150
VDC
dBm
°C
°C
Parameter
Specification
Min.
Typ.
Max.
Caution! ESD sensitive device.
RF Micro Devices believes the furnished information is correct and accurate
at the time of this printing. However, RF Micro Devices reserves the right to
make changes to its products without notice. RF Micro Devices does not
assume responsibility for the use of the described product(s).
Unit
T = 25°C, VCC =3.0V, RF=1960MHz,
LO=1750MHz@-2dBm
Overall
8
Condition
Usable RF Frequency Range
Typical RF Frequency Range
Usable LO Frequency Range
Typical LO Frequency Range
IF Frequency Range
Noise Figure
Input VSWR
1500
Input IP3
Gain
Output Impedance
+5.0
8
2500
1930 to 1990
1200
2500
1430 to 1990
DC to 500
14
<2:1
Single-ended with external matching network.
+7.0
10
1000
Input P1dB
MHz
MHz
MHz
MHz
MHz
dB
dBm
dB
Ω
-7.5
dBm
-5 to +3
30
40
<2:1
dBm
dB
dB
Single-ended with external matching network.
FRONT-ENDS
LO Input
LO Input Range
LO to RF (Mix In) Rejection
LO to IF
LO Input VSWR
Single-ended with external matching network.
Power Supply
Voltage
Current Consumption
8-98
2.7
3.0
20
3.6
26
V
mA
Rev A2 010717
RF2459
Preliminary
Pin
1
Function
LO IN
2
GND2
3
VCC
4
5
GND1
RF IN
6
7
GND3
IF-
8
IF+
Description
Mixer LO single-ended input. The pin is internally DC blocked. External
matching sets impedance.
Interface Schematic
LO IN
Ground for downconverter. Keep traces physically short and connect
directly to ground plane for best performance.
Supply voltage for downconverter. External RF bypassing is required.
The trace length between the bypass caps and the pin should be minimized. Connect ground sides of caps directly to ground.
Same as pin 2.
Mixer RF single-ended input. The pin is internally DC blocked. External
matching sets input impedance.
RF IN
Same as pin 2.
IF output pin. The output is balanced. A current combiner external network performs a differential to single-ended conversion and sets the
output impedance. There must be a DC path from VCC to this pin. this
is normally achieved with the current combiner network. A DC blocking
cap must be present if the IF filter input has a DC path to ground.
IF+
IF-
Same as pin 7, except complementary output.
FRONT-ENDS
8
Rev A2 010717
8-99
RF2459
Preliminary
Application Schematic
VCC
IF Filter
L2
L1
C2
IF OUT
C1
C1
R
4.7 nH
LO IN
1.5 pF
VCC
100 nF
22 pF
1
8
2
7
3
6
4
5
1.5 pF
RF IN
2.2 nH
FRONT-ENDS
8
Output Interface Network
L1, C1 and R form a current combiner which performs
a differential to single-ended conversion at the IF frequency and sets the output impedance. In most cases,
the resonance frequency is independent of R and can
be set according to the following equation:
fIF =
R can then be used to set the output impedance
according to the following equation:
( 4 R1
OUT
8-100
C1 should be chosen as high as possible, while maintaining an RP of L1 that allows for the desired ROUT.
1
L1
2π
(C1 + C EQ)
2
Where CEQ is the equivalent stray capacitance and
capacitance looking into pins 7 and 8. An average
value to use for CEQ is 2.5pF.
R=
where ROUT is the desired output impedance and RP is
the parasitic equivalent parallel resistance of L1.
- 1
RP
) -1
L2 and C2 serve dual purposes. L2 serves as an output bias choke, and C2 serves as a series DC block.
In addition, L2 and C2 may be chosen to form an
impedance matching network if the input impedance of
the IF filter is not equal to ROUT. Otherwise, L2 is chosen to be large (suggested 8.2nH) and C2 is chosen to
be large (suggested 22nF) if a DC path to ground is
present in the IF filter, or omitted if the filter is DC
blocked.
Rev A2 010717
RF2459
Preliminary
Evaluation Board Schematic
RF=1.959MHz, IF=210MHz
(Download Bill of Materials from www.rfmd.com.)
VCC
P1
1
VCC
2
GND
3
N/C
L3
100 nH
C5
9 pF
CON3
J1
LO IN
50 Ω µstrip
R1
16k Ω
L4
180 nH
C7
4 pF
50 Ω µstrip
J3
IF OUT
C6
9 pF
L1
4.7 nH
C1
1.5 pF
VCC
C2
100 nF
C3
22 pF
1
8
2
7
3
6
4
5
C4
1.5 pF
50 Ω µstrip
J2
RF IN
L2
2.2 nH
NOTES:
1) R1, L3, C5, and C6 are chosen to produce an output impedance, ROUT, of 1000 Ω @ 210 MHz.
2) L4 and C7 are chosen to match the 1000 Ω output impedance to 50 Ω for testing purposes.
FRONT-ENDS
8
Rev A2 010717
8-101
RF2459
Preliminary
Evaluation Board Layout 900MHz
Board Size 2.0" x 2.0"
Board Thickness 0.031”, Board Material FR-4
FRONT-ENDS
8
8-102
Rev A2 010717
RF2459
Preliminary
MIXIN VSWR versus VCC
LOIN VSWR versus VCC
1.45
1.95
MIXin, -30º
MIXin, 25º
MIXin, 85º
1.90
1.40
1.35
LOIN
MIXIN VSWR
1.85
1.80
1.30
1.75
1.25
1.70
Loin, -30º
Loin, 25º
Loin, 85º
1.65
2.70
2.80
2.90
3.00
3.10
3.20
3.30
3.40
3.50
1.20
2.70
3.60
2.80
2.90
3.00
VCC (V)
3.10
3.20
3.30
3.40
3.50
3.60
VCC (V)
NF versus VCC
Gain versus VCC
17.0
13.0
16.0
12.0
15.0
11.0
14.0
13.0
FRONT-ENDS
Gain (dB)
Noise Figure
8
10.0
9.0
12.0
8.0
NF, -30º
Gain, -30º
Gain, 25º
NF, 25º
Gain, 85º
NF, 85º
11.0
7.0
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
2.7
2.8
2.9
3.0
VCC (V)
3.1
3.2
3.3
3.4
3.5
3.6
VCC (V)
ICC versus VCC
IIP3 versus VCC
30.0
15.0
13.0
25.0
IIP3 (dBm)
ICC (mA)
11.0
20.0
9.0
7.0
15.0
5.0
Icc, -30º
Icc, 25º
Icc, 85º
IIP3, -30º
IIP3, 25º
IIP3, 85º
10.0
3.0
2.7
2.8
2.9
3.0
3.1
3.2
VCC (V)
Rev A2 010717
3.3
3.4
3.5
3.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
VCC (V)
8-103
RF2459
Preliminary
IP1dB versus VCC
Gain versus LO PIN
VCC = 3.0 V
14.0
-4.0
Gain, -30º
Gain, 25º
13.0
-5.0
Gain, 85º
12.0
Gain (dB)
IP1dB (dBm)
-6.0
-7.0
11.0
10.0
-8.0
9.0
-9.0
IP1dB, -30º
8.0
IP1dB, 25º
IP1dB, 85º
-10.0
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
7.0
-6.0
3.6
-4.0
VCC (V)
-6.0
IP1dB (dBm)
IIP3 (dBm)
FRONT-ENDS
IP1dB, -30º
IP1dB, 25º
IP1dB, 85º
-7.0
8.0
6.0
-8.0
-9.0
4.0
-10.0
2.0
-11.0
-4.0
-2.0
0.0
LO PIN (dBm)
8-104
4.0
VCC = 3.0 V
-5.0
IIP3, -30º
IIP3, 25º
IIP3, 85º
10.0
0.0
-6.0
2.0
IP1dB versus LO PIN
VCC = 3.0 V
12.0
8
0.0
LO PIN (dBm)
IIP3 versus LO PIN
14.0
-2.0
2.0
4.0
-12.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
LO PIN (dBm)
Rev A2 010717