Page 1
Preliminary
RF2713
7
Typical Applications
• Digital and Analog Receivers and
Transmitters
• High Data Rate Digital Communications
Product Description
The RF2713 is a monolithic integrated quadrature modulator/demodulator. The demodulator is used to recover
the I and Q baseband signals from the amplified and filtered IF. Likewise, the inputsand outputs can be reconfigured to modulate I/Q signals onto an RF carrier. The
RF2713 is intended for IF systems where the IF frequency ranges from 100 kHz to 250MHz, and the LO frequency is two times the IF. The IC contains all of the
required components to implement the modulation/
demodulation function and contains a digital divider type
90 ° phase shifter, two double balanced mixers, and baseband amplifiers designed to interface with Analog to Digital Converters. The unit operates from a single 3V to 6V
power supply.
QUADRATURE MODULATOR/DEMODULATOR
• Spread-Spectrum Communication Systems
• Interactive Cable Systems
• Portable Battery-Powered Equipment
.
0
8
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0
4
0
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0
0
8
4
8
6
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0
0
3
5
0
.
0
0.337
0.334
8° MAX
0° MIN
0.034
0.016
0.157
0.150
2
0
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0
.
2
1
.
0
0
0
.
0
1
0.050
4
4
2
9
0.009
0.007
5
UPCONVERTERS
MODULATORS AND
Optimum Technology Matching® Applied
Si BJT GaAs MESFETGaAs HBT
Si Bi-CMOS
ü
I INPUT A
I INPUT B
Q INPUT A
Q INPUT B
BG OUT
IIFOUT
QIFOUT
SiGe HBT
1
2
3
4
5
6
7
Si CMOS
QUAD
DIV.
BY 2
14
VCC
13
LO INPUT
12
GND
11
GND
10
GND
9
I OUT
8
Q OUT
Functional Block Diagram
Package Style: SOIC-14
Features
•3Vto6VOperation
• Modulation or Demodulation
• IF From 100kHz to 250MHz
• Baseband From DC to 50MHz
• Digital LO Quadrature Divider
• Low Power and Small Size
Ordering Information
RF2713 Quadrature Modulator/Demodulator
RF2713 PCBA-D Fully Assembled Evaluation Board (Demodulator)
RF2713 PCBA-M Fully Assembled Evaluation Board (Modulator)
RF Micro Devices, Inc.
7625 Thorndike Road
Greensboro,NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Rev A2 010129
7-17
Page 2
RF2713
Absolute Maximum Ratings
Parameter Rating Unit
Supply Voltage -0.5 to 7.0 V
IF Input Level 500 mV
Operating Ambient Temperature -40 to +85 ° C
Storage Temperature -40 to +150 °C
DC
PP
Preliminary
Caution! ESD sensitive device.
RF Micro Devices believesthe furnishedinformation is correctand 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).
5
Parameter
Min. Typ. Max.
Overall
IF Frequency Range 0.1 to 250 MHz For IF frequencies below ~2.5MHz, the LO
Baseband Frequency Range DC to 50 MHz
Input Impedance 1200 || 1pF Ω Each input, single-ended
Specification
Unit Condition
T=25°C, VCC=3.0V,IF=100MHz,
LO=200MHz, F
should be a square wave. IF frequencies
lower than 100kHz are attainable if the LO is
a square waveand sufficiently large DC
blocking capacitors are used.
MOD
=500kHz
LO
Frequency Twice (2x) the IF frequency. For IF frequen-
UPCONVERTERS
MODULATORS AND
Level 0.06 to 1 V
Input Impedance 500 || 1pF Ω
PP
Demodulator
cies below ~2.5MHz, the LO should be a
square wave. IF frequencies lower than
100kHz are attainable if the LO is a square
wave and sufficiently large DC blocking
capacitors are used.
IFIN=28mVPP,LO=200mVPP,Z
LOAD
=10kΩ
Configuration
LOAD
OUT
OUT
OUT
and Q
=50Ω
and Q
and Q
OUT
OUT
OUT
to GND
to GND
Output Impedance 50 || 1pF Ω Each output, I
Maximum Output 1.4 V
Voltage Gain 20 dB V
22.5 24 25.1 dB V
Noise Figure 24 dB Single Sideband, IF Input of device reac-
35 dB Single Sideband, 50 Ω shuntresistoratIF
Input Third Order Intercept Point
)
(IIP
3
I/Q Amplitude Balance 0.1 0.5 dB
Quadrature Phase Error 1 °
DC Output 800 mV V
2.0 2.4 2.8 V V
DC Offset <10 100 mV I
-22 dBm V
-11 dBm V
-19 VCC=5.0V,IF Input of device reactively
-8 dBm V
-28 dBm V
PP
Saturated
=3.0V
CC
=5.0V
CC
tively matched
Input
=3.0V,IF Input of device reactively
CC
matched
=3.0V,50Ω shunt resistor at IF Input
CC
matched
=5.0V,50Ω shunt resistor at IF Input
CC
=5.0V,IF Input of device reactively
CC
matched, Z
=3.0V,I
CC
=5.0V,I
CC
to Q
OUT
OUT
7-18
Rev A2 010129
Page 3
Preliminary
RF2713
Parameter
Min. Typ. Max.
Modulator Configuration
Maximum Output 200 mV
Input Voltage 90 mV
Voltage Gain 6 dB Single Sideband
I/Q Amplitude Balance 0.1 dB
Quadrature Phase Error <±1 °
Carrier Suppression 25 dBc Unadjusted. Carrier Suppression may be
Sideband Suppression 30 dBc
Specification
Unit Condition
IFIN=28mVPP, LO=200mVPP,
Z
=1200Ω
LOAD
Saturated
PP
Single Sideband, 1dB Gain Compress ion.
PP
optimized further by adjusting the DC offset
level between the A and B inputs.
Power Supply
Voltage 2.7 to 6 V Operating limits
Current 8 mA V
81012mAV
CC
CC
=3.0V
=5.0V
5
UPCONVERTERS
MODULATORS AND
Rev A2 010129
7-19
Page 4
5
RF2713
Preliminary
Pin Function Description (Demodulator Configuration) Interface Schematic
1IINPUTA
2IINPUTB
3QINPUTA
UPCONVERTERS
MODULATORS AND
4QINPUTB
5BGOUT
6 I IF OUT
When the RF2713 is configured as a Quadrature Demodulator, both
mixers are driven by the IF. Whether driving the mixers single-endedly
(as shown in the appl ication schematic) or differentially, the A Inputs
(pins 1 and 3) should be connected to each other.Likewise, both B
Inputs (pins 2 and 4) should be connected to each other. This ensures
that the IF will reach each mixer with the same amplitude and phase,
yielding the best I and Q output amplitude and quadrature balance.
Note that connecting the inputs in parallel changes the input impedance (see the Gilbert Cell mixer equivalent circuit). The single-ended
input impedance (as shown in the application circuit) becomes 630Ω,
but in the balanced configuration, the input impedance would remain
1260Ω.
The mixers are Gilbert Cell designs with balanced inpu ts. The equivalent schematic for one of the mixers is shown on the following page.
The input impedance of each pin is determined by the 1260Ω resistor
in parallel with a transistor base. Note from the schematic that
to V
CC
all four input pins have an internally set DC bias. For this reason, all
four inputs (pins 1 through 4) should be DC blocked. The capacitance
values of the blocking capacitors is determined by the IF frequency.
When dr iving single-endedly, both the series (pins 1 and 3) and shunt
(pins 2 and 4) blocking capacitors should be low impedances, relative
to the 630Ω input impedance.
Same as pin 1, except complementary input. See pin 1.
Same as pin 1, except Q Buffer Amplifier. See pin 1.
Same as pin 3, except complementary input. See pin 1.
Band Gap voltage reference output. This voltage output is held con-
stant over variations in supply voltage and operatin g temperature and
may be used as a reference for other external circuitry. This pin should
not be loaded such that the sourced current exceeds 1mA. This pin
should be bypassed with a large (0.1µF) capacito r.
This pin is not used in the Demodulator Configuration, but must be connected to V
in order to properly bias the I mixer.
CC
INPUT A
V
CC
1260
V
CC
Ω
1260
Ω
INPUT B
IF OUT
7 Q IF OUT
8QOUT
9IOUT
10 GND
11 GND
12 GND
7-20
Same as pin 6, except Q mixer. Same as pin 6.
Q Mixer’s Base band Output. This pin is NOT internally DC blockedand
has DC present due to internal biasing. This is an emitter-follower type
output with an internal 2kΩ pull-down resistor.Even though the AC output impedance is ~50Ω, this pin is intended to drive only high impedance loads such as an opamp or an ADC. The output transistor is NOT
biased su ch that it can drive a large signal into a 50Ω load. DC coupling of this output is permitted provided that the D C impedance to
ground, which appears in parallel with the internal pull-down resistor, is
significantly greater than 2kΩ.
Same as pin 8, except Q Mixer’s Baseband Output. Same as pin 8.
Ground connection. Keep traces physically short and connect imm edi-
ately to ground plane for best performance.
Same as pin 10.
Same as pin 10.
V
CC
I/Q OUT
2k
Ω
Rev A2 010129
Page 5
Preliminary
RF2713
Pin Function Description (Demodulator Configuration) Interface Schematic
13 LO INPUT
14 VCC
High impedance, single-ended modula tor LO input. The LO applied to
this pin is frequency divided by a factor of 2 and becomes the "Carrier".
For direct de m odulation, the Carrier is equal in frequency to the center
of the input IF spectrum (except in the case of SSB/SC). The input
impedance is determined by an internal 500Ω bias resistor to V
external blocking capacitor should be provided if the pin is connected to
a device with DC present. Matching the input impedance is typically
achieved by adding a 51Ω resistor to ground on the source side of the
ACcouplingcapacitor.For the LO input, maximum power transfer is not
critical. The internal LO switching circuits are controlled by the voltage,
not power, into the part. In cases where the LO source does not have
enough available voltage, a reactive match (voltage transformer) can
be used. The LO circuitry consis ts of a limiting amplifier followed by a
digital divider. The limiting amp ensures that the flip-flop type divider is
driven with a square wave over a wide range of input levels. Because
the flip-flop uses the rising and falling edges of the limiter output, the
quadrature accuracy of the Carrier supplied to the mixers is directly
related to the duty cycle, or equivalently to the even harmonic content,
of the input LO signal. In particular, care should be taken to ensure that
the 2xLO level input to this pin is at least 20dB below the LO level. Otherwise, the LO input is not sensitive to the type of input wave form,
except for IF frequencies below ~2.5MHz, in which case the LO input
should be a square wave, in order to ensu re proper triggering of the
flip-flops. IF frequencies below 100kHz are attainable if the LO is a
square wave and sufficiently large DC blocking capacitors are used.
Voltage supply for the entire device. This pin should be well bypassed
at all frequencies (IF, LO, Carrier, Baseband) that are present in the
part.
CC
.An
LO IN
V
CC
500
V
CC
Ω
500
Ω
5
UPCONVERTERS
MODULATORS AND
Rev A2 010129
7-21
Page 6
5
RF2713
Preliminary
Pin Function Description (Modulator Configuration) Interface Schematic
1IINPUTA
UPCONVERTERS
MODULATORS AND
2IINPUTB
3QINPUTA
4QINPUTB
5BGOUT
6 I IF OUT
When the RF2713 is configured as a Quadrature Modulator, each
mixer is driven by an independent baseband modulation channel (I and
Q). The mixers can be driven single-endedly (as shown in the modulator application circuit) or differentially. When driving single-endedly, the
B Inputs (pins 2 and 4) should be connected to each other. This
ensures that the baseband signals will reach each mixer with the same
DC reference, yielding the best carrier suppression. Note that the input
impedance changes according to the drive mode (see the mixer equivalent circuit on the previous page). The single-ended input impedance
(as shown in the modulator application circuit) is 1200Ω for each of the
two inputs. In the balanced configuration, the input impedance would
be 2400Ω for each of the two inputs.
The mixers are Gilbert Cell designs with balanced inpu ts. The equivalent schematic for one of the mixers is shown on the previous page.
The input impedance of each pin is determined by the 1200Ω resistor
in parallel with a transistor base. Note from the schematic that
to V
CC
all four input pins have an internally set DC bias. For this reason, all
four inputs (pins 1 through 4) should be DC blocked. The capacitance
values of the blocking capacitors is determined by the baseband frequency.When driving single-endedly,both the series(pi ns 1 and 3) and
shunt (pins 2 and 4) blocking capacitors should be lowimpedances, relative to the input impedance.
DC bias voltages may be supplied to the inputs pins, if required, in
order to increase the amount of carrier suppression. For example, the
DC levels on the reference inputs (pins 2 and 4) may be offset from
each other by adding different resistor values to ground. These resistors should be larger than 2kΩ. Note from the mixer schematic that all
four input pins have an internally set DC bias. If DC bias is to be supplied, the allowable ranges are limited. For 5V applications, the DC reference on both I pins or both Q pins must not go below 2.7V
no case should the DC voltageon any of the fourpinsgo below2.0V
or above 5.5VDC. IF a DC reference is to be supplied, the source must
also be capable of sinking current. If optimizing carrier suppression fur-
ther is not a concern, it is recommended that all four inputs (pins 1
through 4) be DC blocked.
Same as pin 1, except complementary input. See pin 1.
Same as pin 1, except Q Buffer Amplifier. See pin 1.
Same as pin 3, except complementary input. See pin 1.
Band Gap voltage reference output. This voltage output is held con-
stant over variations in supply voltage and operatin g temperature and
may be used as a reference for other external circuitry. This pin should
not be loaded such that the sourced current exceeds 1mA. This pin
should be bypassed with a large (0.1µF) capacito r.
Connecting pins 6 and 7 to each other accomplishes the summing
function of the upconverted I and Q channels. In addition, because
these outpu ts are open collector type, they must be connected to V
in order to properly bias the Gilbert Cell mixers. Maximum gain and output power occur when the load on these two pins is ~1200Ω.Inmost
applications the impedance of the next stage will be lower and a reactive impedance transforming match should be used if maximum gain
and output level are of concern. Biasing, DC blocking, and impedance
transformation can simultaneously be achieved with the shunt-L /
series-C topology shown in the Application Circuit. The inductance and
capacitance values are chosen to achieve a specific impedance transforming ratio at a specific IF frequency. For applications where the gain
is not as critical, a 1200Ω resistor maybe added in parallel with a
choke inductor in place of the matching inductor. If neither gain nor output level is critical, the inductor may be replaced with a resistor that
sets the desired source impedance to drive the next stage. If the next
stage is an "open" at DC, the blocking capacitor may be eliminated.
, and in
DC
INPUT A
DC
CC
V
CC
1260
V
CC
Ω
1260
Ω
INPUT B
IF OUT
7-22
Rev A2 010129
Page 7
Preliminary
RF2713
Pin Function Description (Modulator Configuration) Interface Schematic
7QIFOUT
8QOUT
9IOUT
10 GND
11 GND
12 GND
13 LO INPUT
14 VCC
Same as pin 6, except complementary input. Same as pin 6.
Pins 8 and 9 are not used in a normal quadrature modulator applica-
tion, and are left unconnec ted. Note, however,that the outputs of each
of these pins are independent upconverted I and Q channels. These
signals may be useful in other applications where independent IF channels are needed. Also note that these outputs are optimized as baseband outputs for the de modulator configuration. As a result, the gain
rolls-off quickly with increasing frequency. This gain ro ll-off will limit the
usefulness of these pins as independent I and Q upconverters. If these
outputs are to be used, please refer to the D emodulator pin descriptions regarding load impedances.
Same as pin 8, except Q Mixer’s Output. Same as pin 8.
Ground connection. Keep traces physically short and connect immedi-
ately to ground plane for best performanc e.
Same as pin 10.
Same as pin 10.
High impedance, single-ended modula tor LO input. The LO applied to
this pin is frequency divided by a factor of 2 and becomes the "Carrier".
For modulation, the Carrier is the center of the modulated output spectrum (except in the case of SSB/SC). The input impedance is determined byan internal 500Ω bias resistor to V
capacitor should be provided if thepin isconn ectedto a devicewith DC
present. Matching the input impedance is typically achieved by adding
a51Ω resistor to ground on the source side of the AC coupling capaci-
tor. For the LO input, maximum power transfer is not critical. The internal LO switching circuits are controlled by the voltage, not power, into
the part. In caseswhere the LOsourcedoes nothave enough available
voltage, a reactive match (voltage transformer) can be used. The L O
circuitry consists of a limiting amplifier followed bya digital divider. The
limiting amp ensures that the flip-flop type divider is driven with a
square wave over a wide range of input levels. Because the flip-flop
uses the rising and falling edges of the limiter output, the quadrature
accuracy of the Carrier supplied to the mixers is directly related to the
duty cycle, or equivalently to the evenharmonic content, of the input LO
signal. In particular, care should be taken to ensure that the 2xLO level
input to this pin is at least 20dB below the LO level. Otherwise, the LO
input is not sensitive to the type of input wave form, except for IF frequencies below ~2.5MH z, in which case the LO input should be a
square wave, in order to ensure proper triggering of the flip-flops. IF frequencies below 100kHz are attainable if the LO is a square wave and
sufficiently large DC blocking capacitors are used.
Voltage supply for the entire device. This pin should be well bypassed
at all frequencies (IF, LO, Carrier, Baseband) that are present in the
part.
. An external blocking
CC
LO IN
V
CC
V
CC
500
2kΩ
I/Q OUT
Ω
V
CC
500
5
Ω
UPCONVERTERS
MODULATORS AND
Rev A2 010129
7-23
Page 8
5
RF2713
Preliminary
Gilbert Cell Mixer Equivalent Circuit
IF+ IF-
LO/2+
LO/2-
I/Q INPUT B
I/Q INPUT A
UPCONVERTERS
MODULATORS AND
7-24
Rev A2 010129
Page 9
Preliminary
Application Schematic - Demodulator Configuration
IF IN
51 Ω
10 nF
10 nF
10 nF
RF2713
V
CC
100 nF
1
2
3
4
5
QUAD
DIV.
BY 2
14
13
100 nF
12
11
10
LO
51 Ω
V
CC
6
7
9
8
I OUT
Q OUT
Application Schematic - Modulator Configuration
V
CC
100 nF
10 nF
LO
51
Ω
BASEBAND I
BASEBAND Q
IF OUT
100 nF
51
Ω
100 nF
51
Ω
100 nF
100 nF
10 nF
1K
1
2
3
4
5
6
7
Ω
V
CC
QUAD
DIV.
BY 2
14
13
12
11
10
9
8
5
UPCONVERTERS
MODULATORS AND
Rev A2 010129
7-25
Page 10
RF2713
Preliminary
Evaluation Board Schematic - Demodulator Configuration
(Download Bill of Materials from www.rfmd.com.)
C5
0.1 uF
14
13
12
11
C4
0.1 uF
50 Ωµstrip
R2
50 Ω
VCC
J4
LO
J1
IF IN
50 Ωµstrip
C2
0.1 uF
C1
0.1 uF
R1
50 Ω
1
2
3
4
QUAD
DIV.
BY 2
5
C3
0.1 uF
VCC
P1
1
NC
GND
2
UPCONVERTERS
MODULATORS AND
P1-3 VCC
3
CON3
5
6
7
10
9
8
2713401-
50 Ωµstrip
50 Ωµstrip
J3
I OUT
J2
Q OUT
Evaluation Board Schematic - Modulator Configuration
C6
14
13
12
11
10
9
8
2713400-
0.1 uF
C5
0.1 uF
50 Ωµstrip
R4
50 Ω
P1
P1-1 VCC
1
2
3
CON3
GND
NC
VCC
J4
LO
J3
IF OUT
VCC
C1
R3
1kΩ
0.1 uF
R1
50 Ω
C4
0.1 uF
1
2
3
4
5
6
7
QUAD
DIV.
BY 2
50 Ωµstrip
J1
I
R2
50 Ωµstrip
J2
Q
50 Ωµstrip
50 Ω
C2
0.1 uF
C3
0.1 uF
7-26
Rev A2 010129
Page 11
Preliminary
Demodulator Configuration (2713 PCBA-D)
RF2713
Evaluation Board Layout
Board Size 2.0” x 2.0”
Board Thickness 0.031”, Board Material FR-4
5
UPCONVERTERS
MODULATORS AND
Rev A2 010129
7-27
Page 12
5
RF2713
Preliminary
Evaluation Board Layout
Modulato r Configuration (2713 PCB A-M)
Board Size 2.0” x 2.0”
Board Thickness 0.031”, Board Material FR-4
UPCONVERTERS
MODULATORS AND
7-28
Rev A2 010129
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