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Optimum Technology Matching® Applied
GaAs HBT
InGaP HBT
GaAs MESFET
SiGe BiCMOS
Si BiCMOS
SiGe HBT
GaAs pHEMT
Si CMOS
Si BJT
GaN HEMT
Functional Block Diagram
RF MICRO DEVICES®, RFMD®, Optimum Technology Matching®, Enabling Wireless Connectivity™, PowerStar®, POLARIS™ TOTAL RADIO™ and UltimateBlue™ are trademarks of RFMD, LLC. BLUETOOTH is a trade-
mark owned by Bluetooth SIG, Inc., U.S.A. and licensed for use by RFMD. All other trade names, trademarks and registered trademarks are the property of their respective owners. ©2006, RF Micro Devices, Inc.
Product Description
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Ordering Information
VCC
QSIG
QREF
GND
VCC
GND
RFOUT
GND
VCC
GND
LO
LOREF
RFREFGND
ISIG
IREF
5
13
12
11
10
14
78
6
9
1516
1
2
3
4
-45°
+45° Σ
RF2850
DIRECT QUADRATURE MODULATOR
The RF2850 is a direct quadrature modulator for use in base stations and
other communications systems. RF2850 supports PCS, GSM, EDGE,
CDMA2000, and UMTS standards. This device features a narrow-band
operation at 1700MHz to 2500MHz with excellent carrier and sideband
suppression and ultra low noise floor. The device is manufactured on an
advanced GaAs HBT process. The RF2850 operates from a single 5V sup-
ply and is packaged in a low cost 4mmx4mm 16-pin leadless package.
Features
Typical Carrier
Suppression>40dBc
Typical Sideband
Suppression>40dBc
Noise Floor better than -
158dBm/Hz
Single 5V Power Supply
Applications
UMTS Base Stations
CDMA Base Stations
GSM-EDGE/EGSM Base Sta-
tions
WLAN and WLL Systems
GMSK,QPSK,DQPSK,QAM
Modulation
RF2850Direct Quadrature Modulator
RF2850 Direct Quadrature Modulator
RF2850PCBA-41X Fully Assembled Evaluation Board
Rev A0 DS050616
9
RoHS Compliant & Pb-Free Product
Package Style: QFN, 16-Pin, 4x4
2 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Absolute Maximum Ratings
Parameter Rating Unit
Supply Voltage -0.5 to +5.3 V
LO Input +10 dBm
Operating Temperature -40 to +85 °C
Storage Temperature -65 to +150 °C
Parameter Specification Unit Condition
Min. Typ. Max.
High Band Performance (1900MHz) with CW Baseband Inputs
LO Input Port
LO Drive Level -5 dBm
LO Input Impedance 50 Ω
LO Port Return Loss 13 dB
Modulation Input
Frequency Range DC 250 MHz
Reference Voltage 2.05 V Baseband common mode voltage
Baseband Input Level 0.25 VP-P 0.25VP-P per pin, 500mV VP-P differential, I/Q
in quadrature
I/Q Signal 200 kHz CW baseband signal
Input Impedance 40 kΩMeasured at DC
Bandwidth (-1dB) 130 MHz 500mV VP-P differential, I/Q at 2.05V DC
Input Bias Current 40 μA
I/Q Modulator Output
RF Frequency Range 1700 2500 MHz T=25°C, VCC=5V
RF Output Power -6 dBm
RF Output Return Loss 15 dB
RF Output P1dB 4 5 dBm
Carrier Suppression 20 25 dBc Unadjusted (see note)
Carrier Suppression 35 55 dBc Adjusted. T=-40°C to +85°C
Sideband Suppression 30 45 dBc Unadjusted
IM3 Suppression 52 dBc Two tone baseband input @ 500mVP-P differen-
tial per tone
Output IP3 15 20 dBm
Broadband Noise Floor -158 -156 dBm/Hz 20MHz offset from LO, all IQ input at bias of
2.05V
DC Parameters
Supply Voltage 5.0 V Specification
4.75 5.25 V Operating limits
Supply Current 60 mA
Note: 20dBc limit for unadjusted carrier suppression is applicable for differential I and Q inputs only.
Caution! ESD sensitive device.
Exceeding any one or a combination of the Absolute Maximum Rating conditions may
cause permanent damage to the device. Extended application of Absolute Maximum
Rating conditions to the device may reduce device reliability. Specified typical perfor-
mance or functional operation of the device under Absolute Maximum Rating condi-
tions is not implied.
RoHS status based on EUDirective2002/95/EC (at time of this document revision).
The information in this publication is believed to be accurate and reliable. However, no
responsibility is assumed by RF Micro Devices, Inc. ("RFMD") for its use, nor for any
infringement of patents, or other rights of third parties, resulting from its use. No
license is granted by implication or otherwise under any patent or patent rights of
RFMD. RFMD reserves the right to change component circuitry, recommended appli-
cation circuitry and specifications at any time without prior notice.
3 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Parameter Specification Unit Condition
Min. Typ. Max.
High Band Performance with PCS CDMA and W-CDMA Baseband Inputs
W-CDMA 3GPP
Channel Power -13 dBm 3.84MHz integrated bandwidth, ESG-D with
LPF
ACPR @ 1960MHz -68 -62 dBc
SNR @ 1960MHz -74 -70 dBc
ACPR @ 2140MHz -65 -62 dBc
SNR @ 2140MHz -74 -70 dBc
Noise Floor @ 20MHz Offset -156 -155 dBm/Hz 20MHz offset from LO
PCS CDMA
Channel Power -13 dBm 1.2288MHz integrated bandwidth
ACPR @ 1960MHz -72 -70 dBc 30kHz integrated bandwidth
W-CDMA 1MHz BW
Channel Power -14 dBm 1MHz integrated bandwidth at adjacent chan-
nel
ACPR @ 2140MHz -74 -71 dBc
SNR @ 2140MHz -85 -82 dBc
Noise Floor @ 20MHz Offset -157 -156 dBm/Hz 20MHz offset from LO
4 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Pin Function Description Interface Schematic
1GND
Ground connection.
2LO
LO input signal. This pin has an internal DC-blocking capacitor. This port is
voltage-driven so matching at different frequencies is generally not
required.
3LOREF
The reference end of local oscillator.
4GND
Ground connection.
5VCC
Power supply. An external capacitor is required.
6I REF
Reference voltage for the I mixer. The DC voltage should be the same as
the DC supplied to I SIG (pin 7). See pin 7 for more information.
The SIG and REF inputs are inputs of a differential amplifier. Therefore, the
REF and SIG inputs are interchangeable. If swapping the I SIG and I REF
pins, the Q SIG and Q REF also need to be swapped to maintain the correct
phase. It is also possible to drive the SIG and REF inputs in a differential
mode which will increase gain.
7I SIG
Baseband input to the I mixer. This pin is DC-coupled. The input drive level
determines output power and linearity performance. For better
carrier/sideband suppression and dynamic range, the drive level should
be as high as possible to meet the required linearity performance. The rec-
ommended DC level for this pin is 2.05V.
8GND
Ground connection.
9RFREF
The reference end of RF input.
10 VCC Power supply. An external capacitor is required.
11 GND Ground connection.
12 RF OUT RF Output. This pin has an internal DC-blocking capacitor. At some frequen-
cies, external matching may be needed to optimize output power.
13 GND Ground connection.
14 Q SIG Baseband input to the Q mixer. This pin is DC-coupled. The input drive level
determines the output power and linearity performance. For better
carrier/sideband suppression and dynamic range, the drive level should
be as high as possible to meet the required linearity performance. The rec-
ommended DC level for this pin is 2.05V.
15 Q REF Reference voltage for the Q mixer. See pin 14 for more information.
16 VCC Power supply. An external capacitor is required.
Pkg
Base
GND Ground connection.
LO
2 pF
VCC
2 pF
VCC
RF OUT
2 pF
VCC
2 pF
VCC
5 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Package Drawing
0.10 CABM
0.35
0.23
Pin 1 ID
0.20 R
2.25
1.95 SQ.
0.65
0.75
0.50 TYP
0.60
0.24
TYP
0.05 C
0.90
0.85
0.70
0.65 0.05
0.00
12°
MAX
-C- SEATING
PLANE
Shaded lead is pin 1.
Dimensions in mm.
0.10 C A
2 PLCS
-A-
4.00 SQ.
0.10 C B
2 PLCS
0.10 C B
2 PLCS
-B-
3.75 SQ
1.87 TYP
0.10 C A
2 PLCS
2.00 TYP
6 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Evaluation Board Schematic
1700MHz to 2500MHz (Differential Drive)
VIN
VCC VCC2
VCC1
C9
100 pF
C10
100 pF
C14
0.5 pF
-45°
+45°
5
13
12
11
10
14
7 86
9
1516
1
2
3
4
Σ
J2
QREF
50 Ω μstrip J4
QSIG
50 Ω μstrip
J3
IREF
50 Ω μstrip J5
ISIG
50 Ω μstrip
L1
1 nH
L2
1 nH
50 Ω μstrip
J1
LO
C12
3.9 pF
C13
3.9 pF
X1
2.1 GHz X2
2.1 GHz
50 Ω μstrip J6
RF OUT
VCC1
L3
100 nH
VCC2
L4
100 nH
C3
100 pF
P1
C1
2.2 pF
7 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Evaluation Board Layout
Board Size 2.00” x 2.00”
Board Thickness 0.042” (±10%), Board Material FR-4
8 of 8
RF2850
Rev A0 DS050616
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
