NO
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5-17
Product Description
Ordering Information
Typical Applications
Features
Functional Block Diagram
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Optimum Technology Matching Applied
Si BJT
GaAs MESFET
GaAs HBT
Si Bi-CMOS
SiGe HBT
Si CMOS
InGaP/HBT
GaN HEMT
SiGe Bi-CMOS
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
I REF
Q REF
VCC1
MIXOUT
GND1
GND1
LO
GND3
ISIG
QSIG
GND1
VCC2
PD
GND1
GND2
RFOUT
POWER
CONTROL
-45
+45
RF2424
UHF QUADRATURE MODULATOR
Digital Communications Systems
Spread Spectrum Communication Systems
GMSK,QPSK,DQPSK,QAM Modulation
GSM and D-AMPS Systems
AM, SSB, DSB Modulation
Image-Reject Upconverters
The RF2424 is a monolithic integrated quadrature modu-
lator IC capable of universal direct modulation for high-
frequency AM, PM, or compound carriers. Maximum out-
put power is +7.5dBm, which is achieved with low input I
and Q signal levels. This low-cost IC implements differen-
tial amplifiers for the modulation inputs, 90 carrier phase
shift network, carrier limiting amplifiers, two matched dou-
ble-balanced mixers, summing amplifier, and an output
RF amplifier which will drive 50
from 700MHz to
1000MHz.
Single 2.7V to 5.5V Power Supply
+7.5dBm Output Power
No Tuning Required
Low LO Input Level
Digitally Controlled Power Down Mode
700MHz to 1000MHz Operation
RF2424
UHF Quadrature Modulator
RF2424 PCBA
Fully Assembled Evaluation Board
0
Rev A7 021008
0.157
0.150
0.025
0.012
0.008
0.196
0.189
0.2440
0.2284
0.0688
0.0532
0.050
0.016
0.0098
0.0075
8 MAX
0MIN
NOTES:
1. Shaded lead is Pin 1.
2. All dimensions are excluding mold flash.
3. Lead coplanarity - 0.005 with respect to datum "A".
-A-
0.0098
0.0040
Package Style: SSOP-16
NOT FOR NEW DESIGNS
!
5-19
RF2424
Rev A7 021008
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Pin
Function
Description
Interface Schematic
1
I REF
Reference voltage for the I mixer. This voltage should be the same as
the DC voltage supplied to the I SIG pin. A voltage of 1.6V is recom-
mended. 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 balanced mode. If single ended operation is desired
then the input is applied to I SIG, pin 16. In that case, I REF and Q REF
are tied together and AC coupled to ground. To obtain a carrier sup-
pression of better than 40dB, I REF may be tuned 20mV relative to
the I SIG. Without tuning, it will typically be better than 25dB.
2
Q REF
Reference voltage for the Q mixer. This voltage should be the same as
the DC voltage supplied to the Q SIG pin. A voltage of 1.6V is recom-
mended. The SIG and REF inputs are inputs of a differential amplifier.
Therefore the REF and SIG inputs are interchangeable. If swapping the
Q SIG and Q REF pins, the I SIG and I REF also need to be swapped
to maintain the correct phase. It is also possible to drive the SIG and
REF inputs in a balanced mode. If single ended operation is desired
then the input is applied to Q SIG, pin 15. In that case, Q REF and Q
REF are tied together and AC coupled to ground. To obtain a carrier
suppression of better than 40dB, Q REF may be tuned 20mV relative
to the Q SIG. Without tuning, it will typically be better than 25dB.
3
VCC1
Power supply for the I mixer, Q mixer and the RF Output amplifier.
4
MIX OUT
MIXOUT: Combined output of the I mixer and Q mixer. By changing the
inductor value, maximum RF output is tuned to different frequency. If
the inductor value is changed, the RF output match needs to be
adjusted for 50
output impedance.
5
GND1
Ground connection for the LO and baseband amplifiers and mixers.
6
GND1
Same as pin 5.
7
LO IN
The input of the phase shifting network.
8
GND3
Ground connection for the LO phase shift network.
9
RF OUT
RF Output. An external LC matching network is needed for a 50
match.
10
GND2
Ground connection for the RF output stage.
11
GND1
Same as pin 5.
12
PD
Power Down control. When this pin is "low", all circuits are shut off.
13
VCC2
Power supply for all circuits except mixers and output amplifier.
14
GND1
Same as pin 5.
15
Q SIG
Baseband input to the Q mixer. Maximum output power is obtained
when the input signal has a peak to peak amplitude of 400mV. The DC
level for this pin is 1.6V, same as QREF.
See pin 2.
16
I SIG
Baseband input to the Q mixer. Maximum output power is obtained
when the input signal has a peak to peak amplitude of 400mV. The DC
level for this pin is 1.6V, same as QREF.
See pin 1.
Q REF
Q SIG
BIAS
BIAS
Q REF
Q SIG
BIAS
BIAS
MIX OUT
LO
BIAS
RF OUT
PD
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