RFMD RF2456

RF2456
6
CDMA/FM DOWNCONVERTER
Typical Applications
• CDMA/FM Cellular Systems
• General Purpose Downconverter
• Supports Dual-Mode AMPS/CDMA
• Commercial and Consumer Systems
• Supports Dual-Mode TACS/CDMA
• Portable Battery-Powered Equipment
Product Description
-A-
0.157
0.150
0.0098
0.0040
0.012
0.008
0.196
0.189
6
0.025
0.0688
0.0532
0.2440
0.2284
8° MAX
0°MIN
0.050
0.016
MIXERS
The RF2456 is a receiver dual downconverter designed
for the receive section of dual-mode CDMA/FM cellular
applications. It is designed to downconvert RF signals
while providing 13dB gain in CDMA mode, and 7dB gain
in FM mode. It also features digital control of IF output
selection and power down mode. Noise Figure, IP3, and
other specs are designed to be compatible with the IS-95
Interim Standard for CDMA cellular communications. The
IC is manufactured on an advanced Silicon Bipolar process and packaged in an SSOP-16.
0.0098
0.0075
NOTES:
1. Shaded lead is Pin 1.
2. All dimensions are excluding mold flash.
3. Lead coplanarity - 0.005 with respect to datum "A".
Optimum Technology Matching® Applied
ü
Si BJT
GaAs HBT
GaAs MESFET
Si Bi-CMOS
SiGe HBT
Si CMOS
Package Style: SSOP-16
Features
• Dual Mode CDMA/AMPS
VCC 1
16 GND
FM- 2
15 GND
FM+ 3
14 GND
GND 4
13 BYP
CDMA+ 5
12 MIXER IN
CDMA- 6
11 GND
IF SELECT7
PD 8
10 LO9 LO+
Functional Block Diagram
Rev B6 010717
• Dual Mode JCDMA/TACS
• Digitally Selectable IF Outputs
• 500MHz to 1100MHz Operation
• Power Down Mode
Ordering Information
RF2456
RF2456 PCBA
CDMA/FM Downconverter
Fully Assembled Evaluation Board
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
6-1
RF2456
Absolute Maximum Ratings
Parameter
Supply Voltage
Input LO and RF Levels
Operating Ambient Temperature
Storage Temperature
Parameter
Rating
Unit
-0.5 to +5.0
+6
-40 to +85
-40 to +150
VDC
dBm
°C
°C
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=881MHz,
LO=966MHz @ 0dBm, IF1= CDMA,
IF2=FM
Overall
RF Frequency Range
LO Frequency Range
IF Frequency Range
Conversion Gain
6
12.5
5
Noise Figure
MIXERS
Input VSWR
Input IP3
Condition
+3.0
+3.0
Input P1dB
MIX IN to IF1, IF2 Rejection
IF1, IF2 Output Freq. Range
Output Impedance
200 to 1000
500 to 1100
0.1 to 250
13.0
7
12
13
<1.5:1
<2:1
+3.5
+10.0
-7
-4
35
70 to 100
>1
870
MHz
MHz
MHz
dB
dB
dB
dB
dBm
dBm
dBm
dBm
dB
MHz
kΩ
Ω
IF1, 1kΩ balanced load.
IF2, 870Ω load.
IF1 single sideband.
IF2 single sideband
IF1 with external matching
IF2 with external matching
IF1
IF2
IF1
IF2
With external IF interface network
IF1, balanced, open collector
IF2, single ended, with external inductor.
LO Input
LO Input Range
LO IN to RF Input Rejection
LO IN to IF1, IF2 Rejection
LO Input VSWR
-10
-3
20
15
<2:1
2.5
0
3.0
18
15
4.0
21
16
5
dBm
dB
dB
IF1 with external matching network
IF2 with external matching network
Power Supply
Voltage
Current Consumption
6-2
2.7
V
mA
mA
µA
IF1 selected
IF2 selected
Power down (PD=0)
Rev B6 010717
RF2456
Pin
1
Function
VCC
Description
Supply Voltage for the mixers, bias circuits, and control logic. External
RF and IF bypassing is required. The trace length between the pin and
the bypass capacitors should be minimized. The ground side of the
bypass capacitors should connect immediately to ground plane.
Interface Schematic
VCC2
BIAS
LO OUT
IF2-
Same as pin 3, except complimentary output. For typical single ended
operation, this pin is connected directly to VCC.
3
IF2+
FM IF Output pin. This is a balanced output, but is typically used as a
single-ended output. The internal circuitry, in conjunction with an external matching/bias inductor to VCC, sets the operating impedance. This
inductor is typically incorporated in the matching network between the
output and IF filter. The net output impedance, including the external
inductor, is about 870Ω at 85MHz. Because this pin is biased to VCC, a
DC blocking capacitor must be used if the IF filter input has a DC path
to ground. See Application Schematic.
Ground connection. For best performance, keep traces physically short
and connect immediately to ground plane.
CDMA IF Output pin. This is a balanced output. The internal circuitry, in
conjunction with an external matching/bias inductor to VCC, sets the
operating impedance. This inductor is typically incorporated in the
matching network between the output and IF filter. The net output
impedance, including the external inductor, at 85MHz is higher than
1kΩ, even though the part is designed to drive a 1kΩ load. Because
this pin is biased to VCC, a DC blocking capacitor must be used if the IF
filter input has a DC path to ground. See Application Schematic.
Same as pin 5, except complementary output.
4
GND
5
IF 1+
6
7
8
IF 1IF SELECT
PD
Same as pin 9 except complementary input.
12
MIX IN
Rev B6 010717
IF1+ GND2 IF1-
1.2
pF
Ground connection for the mixer. For best performance, keep traces
physically short and connect immediately to ground plane.
Mixer RF Input Pin. This pin is internally DC biased and should be DC
blocked if connected to a device with DC present. External matching
network sets RF and IF impedance for optimum performance.
1.2
pF
See pin 5.
LO IN+
LO INGND
GND
GND
GND
6
PD
10
11
14
15
16
2.1 kΩ
Power down pin. A logic “low” turns the part off. A logic “high” (>1.6V)
turns the part on. In addition, pin 7 (IF SELECT) should also be taken
low during power down.
Mixer LO Balanced Input Pin. For single-ended input operation, this pin
is used as an input and pin 10 is bypassed to ground.
IF2-
8.5 pF
C1
LO IN+
BYP
IF2+
Control line for IF out select. A logic “low” enables the FM output. A
logic “high” enables the CDMA output. The threshold voltage is 1.6V,
and the pin draws less than 50µA when selected.
9
13
See pin 3.
MIXERS
2
50 kΩ
50 kΩ
LO IN-
See pin 9.
MIX IN
Internal voltage reference. External RF and IF bypassing is required.
The trace length between the pin and the bypass capacitors should be
minimized. The ground side of the bypass capacitors should connect
immediately to ground plane.
Same as pin 4.
Same as pin 4.
Same as pin 4.
6-3
RF2456
Application Schematic
VCC
1 µF
33 nF
1
16
2
15
3
14
4
13
5
12
6
11
IF SELECT
7
10
PD
8
9
FM SAW Filter
L
FM IF OUT
33 nF
L
L
33 nF
CDMA SAW Filter
CDMA IF OUT
L
15 nH
MIX IN
15 nH
3.3 pF
6
5.6 nH
LO IN
33 nF
MIXERS
Evaluation Board Schematic
(Download Bill of Materials from www.rfmd.com.)
P1
NOTE:
**Core: Fair-Rite Balun #2865002402
L12: 3 turns #30 AWG (Green)
L34: 12 turns #32 AWG (Red)
One turn = One pass through BOTH holes winding starts and finishes on same end of core.
L12 and L34 exit opposite ends of core.
P1-1
P2
1
VCC
2
GND
P2-1
P2-3
3
1
IF SELECT
2
GND
3
ENABLE
50 Ω µstrip
C1
33 nF
J5
1
16
2
15
1
R3
10 Ω
50 Ω µstrip
C10
+ 1 uF
C5
33 nF
L1
150 nH
C3
9 pF
VCC
J3
CDMA IF1
50 Ω µstrip
R1
33 Ω
T1
**XFMER
L3
3.3 uH
L2
390 nH
R2
68 Ω
C4
9 pF
3
14
4
13
5
12
6
11
7
10
8
9
2 GND
C9
33 nF
L4
3.3 uH
VCC
IF SELECT
ENABLE
6-4
2456400 Rev A
Enable
0
0
1
1
IF Select
0
1
0
1
Stage
Off
Off
FM
CDMA
L7
15 nH
C8
33 pF
OUT
C2
10 pF
L8*
TBD
L6
15 nH
F1*
DNI
3
J2
FM IF2
IN
VCC
50 Ω µstrip
J1
RF IN
C7
1.5 pF
R4
220 Ω
L5
8.2 nH
C6
33 nF
50 Ω µstrip
J4
LO IN
Rev B6 010717
RF2456
Evaluation Board Layout
Board Size 3.070" X 2.928"
Board Thickness 0.056”, Board Material FR-4
MIXERS
6
Rev B6 010717
6-5
RF2456
MIXERS
6
6-6
Rev B6 010717
RF2456
FM Gain versus Temperature over Frequency,
6.6
13.6
6.4
13.5
6.2
FM Gain @ T=-40
FM Gain @ T=26
6.0
VCC = 3V, LO = -3 dBm
13.7
Gain (dB)
Gain (dB)
CDMA Gain versus Temperature over Frequency,
VCC = 3 V, LO = -3 dBm
6.8
13.4
13.3
FM Gain @ T= 85
5.8
13.2
5.6
13.1
5.4
869.0
13.0
869.0
CDMA Gain @ T=-40
CDMA Gain @ T=26
CDMA Gain @ T= 85
874.0
879.0
884.0
889.0
894.0
874.0
879.0
884.0
889.0
Frequency (MHz)
Frequency (MHz)
FM IIP3 versus Temperature over Frequency,
CDMA IIP3 versus Temperature over Frequency,
VCC = 3 V, LO = -3 dBm
6
VCC = 3 V, LO = -3 dBm
9.0
MIXERS
11.5
894.0
11.0
8.0
10.5
7.0
IIP3 (dBm)
IIP3 (dBm)
10.0
9.5
9.0
8.5
6.0
CDMA iIP3 @ T=-40
5.0
CDMA iIP3 @ T=26
CDMA iIP3 @ T= 85
8.0
FM iIP3 @ T=-40
4.0
FM iIP3 @ T=26
7.5
FM iIP3 @ T= 85
7.0
869.0
874.0
879.0
884.0
889.0
3.0
869.0
894.0
874.0
Frequency (MHz)
884.0
889.0
894.0
Frequency (MHz)
FM Gain versus Temperature over LO,
CDMA Gain versus Temperature over LO,
VCC = 3 V, Frequency = 881 MHz
6.6
879.0
VCC = 3 V, Frequency = 881 MHz
14.0
CDMA Gain @ T=-40
13.9
6.4
CDMA Gain @ T=26
CDMA Gain @ T= 85
13.8
6.2
13.7
Gain (dB)
Gain (dB)
6.0
5.8
13.6
13.5
13.4
5.6
13.3
5.4
13.2
FM Gain @ T=-40
FM Gain @ T=26
5.2
13.1
FM Gain @ T= 85
5.0
-6.0
-5.0
-4.0
-3.0
Frequency (MHz)
Rev B6 010717
-2.0
-1.0
0.0
13.0
-6.0
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
LO (dBm)
6-7
RF2456
FM IIP3 versus Temperature over LO,
CDMA IIP3 versus Temperature over LO,
VCC = 3 V, Frequency = 881 MHz
12.0
VCC = 3 V, Frequency = 881 MHz
8.0
FM iIP3 @ T=-40
7.0
FM iIP3 @ T=26
11.5
FM iIP3 @ T= 85
6.0
11.0
5.0
4.0
IIP3 (dBm)
IIP3 (dBm)
10.5
10.0
9.5
3.0
2.0
1.0
0.0
9.0
CDMA iIP3 @ T=-40
-1.0
CDMA iIP3 @ T=26
8.5
-2.0
8.0
-6.0
-5.0
-4.0
-3.0
-2.0
-1.0
CDMA iIP3 @ T= 85
-3.0
-6.0
0.0
-5.0
-4.0
-3.0
LO (dBm)
6
FM Gain versus Temperature over VCC,
-1.0
0.0
CDMA Gain versus Temperature over VCC,
Frequency = 881 MHz, LO = -3 dBm
6.5
-2.0
LO (dBm)
Frequency = 881 MHz, LO = -3 dBm
13.7
MIXERS
6.4
13.6
6.3
13.5
6.1
Gain (dB)
Gain (dB)
6.2
6.0
5.9
FM Gain @ T=-40
5.8
13.4
13.3
13.2
FM Gain @ T=26
5.7
FM Gain @ T= 85
CDMA Gain @ T=-40
13.1
CDMA Gain @ T=26
5.6
CDMA Gain @ T= 85
5.5
13.0
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
2.7
4.0
2.8
2.9
3.0
3.1
3.2
VCC (V)
3.4
3.5
3.6
3.7
3.8
3.9
4.0
VCC (V)
FM IIP3 versus Temperature over VCC,
CDMA IIP3 versus Temperature over VCC,
Frequency = 881 MHz, LO = -3 dBm
12.0
3.3
Frequency = 881 MHz, LO = -3 dBm
9.0
8.0
11.0
7.0
6.0
IIP3 (dBm)
IIP3 (dBm)
10.0
9.0
8.0
5.0
4.0
3.0
2.0
FM iIP3 @ T=-40
7.0
CDMA iIP3 @ T=-40
FM iIP3 @ T=26
CDMA iIP3 @ T=26
1.0
FM iIP3 @ T= 85
CDMA iIP3 @ T= 85
6.0
0.0
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
VCC (V)
6-8
3.5
3.6
3.7
3.8
3.9
4.0
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
4.0
VCC (V)
Rev B6 010717