RFMD RF2486

RF2486
8
PCS LOW NOISE AMPLIFIER/MIXER
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
0.157
0.150
1
0.012
0.008
0.344
0.337
0.025
Si BJT
üSi Bi-CMOS
GaAs HBT
GaAs MESFET
SiGe HBT
Si CMOS
0.0688
0.0532
0.2440
0.2284
8
8°MAX
0°MIN
0.050
0.016
Optimum Technology Matching® Applied
0.0098
0.0040
0.0098
0.0075
Package Style: SSOP-24
Features
24 NC
• Complete Receiver Front-End
VCC1 2
23 GND9
• High Dynamic Range
VCC2 3
22 VCC4
GND1 4
21 GND8
NC 1
LNA IN 5
20 LNA OUT
GND2 6
19 GND7
GND3 7
18 MIX RF IN
NC 8
16 IF-
VCC3 10
15 IF+
LO IN 12
14 GND5
13 LO BUFF OUT
Functional Block Diagram
Rev A7 010717
• Single 3.6V Power Supply
• External LNA IP3 Adjustment
• 1500MHz to 2500MHz Operation
17 GND6
GND4 9
LO BUFF EN 11
FRONT-ENDS
The RF2486 is a monolithic integrated receiver front-end
for PCS, PHS, and WLAN applications. The IC contains
all of the required components to implement the RF functions of the receiver front-end except for the passive filtering and LO generation. It contains an LNA (low-noise
amplifiers), a double-balanced Gilbert cell mixer, a balanced IF output, an LO isolation buffer amplifier, and an
LO output buffer amplifier for providing the buffered LO
signal as an output. The IC is designed to operate from a
single 3.6V power supply.
Ordering Information
RF2486
PCS Low Noise Amplifier/Mixer
RF2486 PCBA-L Fully Assembled Evaluation Board 1.96GHz
RF2486 PCBA-H Fully Assembled Evaluation Board 2.4GHz
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
8-105
RF2486
Absolute Maximum Ratings
Parameter
Supply Voltage
Input LO and RF Levels
Ambient Operating Temperature
Storage Temperature
Parameter
Rating
Unit
-0.5 to 5.5
+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 =3.6V, RF=1959MHz,
LO=1749MHz @ +1 dBm
Overall
RF Frequency Range
LO Frequency Range
IF Frequency Range
1500
1200
DC
2500
2500
500
MHz
MHz
MHz
28
dB
dBm
dB
Cascaded Performance
Cascade Conversion Gain
Cascade Input IP3
Cascade Noise Figure
1kΩ balanced load, 2.5dB Image Filter Loss.
24
-17
27
-16
3.6
First Section (LNA)
FRONT-ENDS
8
Condition
Noise Figure
Input VSWR
1.8
1.5:1
Input IP3
Gain
Reverse Isolation
Output VSWR
dB
2.0:1
+4
dBm
+8.5
13.5
23
<1.5:1
dBm
dB
dB
10
1.5:1
-5
16
1
dB
Second Section (Mixer)
Noise Figure
Input VSWR
Input IP3
Conversion Gain
Output Impedance
Single Sideband
The LNA section may be left unused. Power
is not connected to pin 1. The performance
is then as specified for the Second Section
(Mixer).
dBm
dB
kΩ
Input is internally matched for optimum noise
figure from a 50Ω source.
IP3 may be increased 10dB by connecting
pin 22 to VCC through the matching inductor.
The LNA’s current then increases by 10mA.
Other in-between IP3 versus ICC trade-offs
may be made. See pin description for pin 20.
R2=Open
R2=Short
With 1kΩ balanced load.
Single Sideband
Balanced
LO Input
LO Input Range
LO Output Level
-3
-7
LO to RF (Mix In) Rejection
LO to IF1, IF2 Rejection
LO Input VSWR
-3
-22
30
20
1.5:1
+3
+1
-14
dBm
dBm
dBm
dB
dB
Buffer On, +1dBm input
Buffer Off, +1dBm input
Single ended
Power Supply
Voltage
Current Consumption
8-106
2.7
3.6
7
52
48
5.0
V
mA
mA
mA
LNA only
LNA + Mixer, LO Buffer On
LNA + Mixer, LO Buffer Off
Rev A7 010717
RF2486
Function
NC
VCC1
3
VCC2
4
GND1
5
LNA IN
6
7
GND2
GND3
8
9
10
NC
GND4
VCC3
11
LO BUFF
EN
12
LO IN
13
LO BUFF
OUT
14
GND5
15
IF+
16
17
IFGND6
18
MIX RF IN
19
GND7
Rev A7 010717
Description
Interface Schematic
No connection. This pin may be grounded (recommended) or left open.
Supply voltage for the mixer and RF buffer amplifier. External RF
bypassing is required. The trace length between the pin and the bypass
capacitor should be minimized. The ground side of the bypass capacitor should connect immediately to ground plane.
Supply voltage for the LNA. External RF bypassing is required. The
trace length between the pin and the bypass capacitor should be minimized. The ground side of the bypass capacitor should connect immediately to ground plane.
Ground connection for the LNA. For best performance, keep traces
physically short and connect immediately to ground plane.
RF input pin for the LNA. This pin is internally matched for minimum
noise figure (NOT for minimum VSWR), given a 50Ω source impedance. This pin is not internally DC-blocked.
150 Ω
VCC1
VCC4
BIAS
LNA IN
Same as pin 4.
Ground connection for the RF buffer amplifier. For best performance,
keep traces physically short and connect immediately to ground plane.
No connection. This pin may be grounded (recommended) or left open.
Same as pin 7.
Supply voltage for both LO buffer amplifiers. External RF bypassing is
required. The trace length between the pin and the bypass capacitor
should be minimized. The ground side of the bypass capacitor should
connect immediately to ground plane.
Enable pin for the LO output buffer amplifier. This is a digitally controlled input. A logic "high" (≥3.1V) turns the buffer amplifier on, and the
current consumption increases by 3mA (with -2dBm LO input). A logic
"low" (≤0.5V) turns the buffer amplifier off.
Mixer LO input pin. This pin is internally DC-blocked and matched to
50Ω.
Optional buffered LO output. This pin is internally DC-blocked and
matched to 50Ω. The buffer amplifier is switched on or off by the voltage level at pin 11.
Ground connection for both LO buffer amplifiers. For best performance,
keep traces physically short and connect immediately to ground plane.
Open-collector IF output pin. This is a balanced output. The output
impedance is set by an internal 1000Ω resistor to pin 16. Thus the differential IF output impedance is 1000Ω. The resistor sets the operating
impedance, but an external choke or matching inductor to VCC must be
supplied in order to bias this output. This inductor is typically incorporated in the matching network between the output and IF filter. 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.
Same as pin 15, except complementary output.
8
7.5 kΩ
LO BUFF EN
FRONT-ENDS
Pin
1
2
IF-
IF+
1 kΩ
See pin 15.
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-blocked and matched to
50Ω.
Same as pin 17.
8-107
RF2486
Pin
20
Function
LNA OUT
21
22
GND8
VCC4
23
24
GND9
NC
Description
Interface Schematic
LNA output pin. This is an open-collector output. This pin is typically
connected to pin 22 through a bias/matching inductor. This inductor, in
conjunction with a series blocking/matching capacitor, forms a matching network to the 50Ω image filter and provides bias (see application
schematic). The LNA’s IP3 may be increased 10dB by connecting pin
20 to VCC through the inductor. The LNA’s current then increases by
10mA. Other in-between IP3 versus ICC trade-offs may be made by
connecting resistance values between VCC and the matching inductor.
The two reference points for consideration are with 150Ω used, which
is what connection to pin 22 achieves, the input IP3 is +5.5dBm and the
LNA ICC is 5mA. Using no resistance, the input IP3 is +15.5 dBm and
the LNA ICC is 15 mA. Desired operating points in between these values may be roughly interpolated.
Same as pin 17.
LNA OUT
Output supply voltage for the LNA output (pin 20). This pin is typically
connected to pin 20 through a bias/matching inductor (see application
schematic). External RF bypassing is required. The trace length
between the pin and the bypass capacitor should be minimized. The
ground side of the bypass capacitor should connect immediately to
ground plane.
Same as pin 17.
See pin 2.
No connection. This pin may be grounded (recommended) or left open.
Application Schematic
1.96GHz, 210MHz IF
8
FRONT-ENDS
See evaluation
board
R2
1
VCC
1 nF
22 pF
VCC
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
22 pF
1.8 nH
2 pF
LNA OUT
22 pF
22 pF
LNA2 IN
SAW
Filter
22 pF
MIX IN
VCC
1 nF
22 pF
IF SAW
Filter
470 nH
100 pF
1
2
1 kΩ
BUF ENBL
1 nF
22 pF
470 nH
470 nH
100 pF
1 nF
VCC
22 pF
4.7 µF
LO IN
2.7 nH
8-108
LO OUT
Rev A7 010717
RF2486
Evaluation Board Schematic
1.96GHz, 210MHz IF
(Download Bill of Materials from www.rfmd.com.)
VCC
R 2*
SAT
VCC
C 10
1 nF
J1
L N A 2 IN
C 18
22 pF
50 Ω µstrip
C5
2 2 pF
1
24
2
23
3
22
4
21
5
20
6
19
VCC
C6
1 nF
R1
1 kΩ
J2
LO IN
50 Ω µstrip
L1
2.7 n H
F L1*
C2*
22 pF
**S ee N o te s**
50 Ω µs trip
J5
M IX E R IN
18
8
17
9
16
10
15
11
14
12
13
J6
LNA OUT
C 2a
22 p F
C8
5 pF
T1
C 16
10 0 pF
L5
22 0 nH
C 11
1.0 pF
J4
IF O U T
L4
4 7 nH
TOKO
BUFF EN
C14
1 nF
C 1a
22 pF
50 Ω µstrip
C1*
22 pF
50 Ω µs trip
7
C 12
22 pF
**S e e N otes **
C4
1 .5 pF
50 Ω µstrip
**S ee N ote s**
C3
2 2 pF
C7
2 2 pF
50 Ω µstrip
2 486400 -
C 17
10 0 pF
L3
47 0 nH
L2
47 0 nH
50 Ω µs trip
J3
LO OUT
8
VCC
G nd
C9
2 2 pF
VCC
+ C 15
4.7 u F
P1
B U F F E R E N A B LE
*C om p on ents n ot no rm a lly p op ula ted.
NO TE S:
C 1 1 selecte d to fine tu ne L 4 for IF ou tput m a tch a t 210 M H z.
R 2 is no rm ally n ot po pu late d. F or ap plica tion s req uiring a dd itio nal LN A IP 3, see the d ata s hee t fo r
rec om m end ed resistanc e va lue s.
C 1 a an d C 2a a re no rm ally n ot po pulate d. If C 1a an d C 2 a a re po pulated , the L N A a nd m ixe r can b e
tes te d in de pen de ntly . In th is c ase , C 1 a nd C 2 s hou ld b e re m ov ed.
To use the p art w ith o nbo ard filter, d o no t p op ula te C 1a, a nd C 2a .
U se C 1 and C 2 ins tead . Th is w ill allow ca sca ded ope ratio n o nly .
Rev A7 010717
1
2
VCC
FRONT-ENDS
C 13
1 nF
3
8-109
RF2486
Evaluation Board Schematic
2.4GHz, 280MHz IF
(Download Bill of Materials from www.rfmd.com.)
VCC
R2*
SAT
VCC
C10
1 nF
J1
LNA2 IN
C5
22 pF
1
24
2
23
3
C3
22 pF
C4
2.0 pF
4
21
5
20
6
19
7
VCC
R1
1 kΩ
BUFF EN
8
C14
1 nF
J2
LO IN
C7
22 pF
50 Ω µstrip
**See Notes**
50 Ω µstrip
J6
LNA OUT
C1*
22 pF
L1
1.8 nH
FL1*
C2*
22 pF
50 Ω µstrip
C6
1 nF
C1a
22 pF
22
50 Ω µstrip
C12
22 pF
50 Ω µstrip
**See Notes**
50 Ω µstrip
J5
MIXER IN
18
8
17
9
16
10
15
11
14
12
13
C2a
22 pF
C16
100 pF
C8
6 pF
T1
TOKO
L5
180 nH
C11
1.0 pF
J4
IF OUT
L4
22 nH
C17
100 pF
L3
470 nH
L2
470 nH
2486401-
J3
LO OUT
FRONT-ENDS
50 Ω µstrip
VCC
C13
1 nF
C9
22 pF
VCC
C15 +
4.7 uF
Gnd
*Components not normally populated.
NOTES:
C11 selected to Fine Tune L4 for IF Output Match at 280 MHz.
R2 is normally not populated. For applications requiring additional LNA IP3, see the datasheet for recommended resistance values.
C1a and C2a are normally not populated. If C1a and C2a are populated, the LNA and mixer can be tested independently.
In this case, C1 and C2 should be removed.
To use the part with onboard filter, do not populate C1a, and C2a.
Use C1 and C2 instead. This will allow cascaded operation only.
8-110
P1
P1-1
P1-3
1
BUFFER ENABLE
2
GND
3
VCC
CON3
Rev A7 010717
RF2486
Evaluation Board Layout 1.96GHz
Board Size 3.0” x 3.0”
Board Thickness 0.075.6”, Board Material FR-4, Multi-Layer
(8 mils between Layers 1 and 2, 31 mils between Layers 2 and 3, 1 ounce copper all layers)
FRONT-ENDS
8
Rev A7 010717
8-111
RF2486
Evaluation Board Layout 2.4GHz
Board Size 3.0” x 3.0”
FRONT-ENDS
8
8-112
Rev A7 010717