RF2423

RF2423 RFMD | Alldatasheet

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Functional Block Diagram RF Micro Devices, Inc.

7625 Thorndike Road

Greensboro, NC 27409, USA T el (336) 664 1233 Fax (336) 664 0454 http://www.rfmd.com Optimum Technology Matching® Applied Si BJT GaAs MESFETGaAs HBT Si Bi-CMOS SiGe HBT Si CMOS GC PHASE VDD1 GND2 LO IN GND1 I REF I SIG STAND BY VDD2 VDD3 GND3 RF OUT GND4 Q REF Q SIG POWER CONTROL Σ -45° +45° RF2423 100mW SPREAD-SPECTRUM TRANSMITTER IC  Digital and Analog Communication Systems  Spread-Spectrum Communication Systems  Portable Battery-Powered Equipment  GMSK, QPSK, DQPSK, QAM Modulation  AM, SSB, DSB Modulation The RF2423 is a monolithic integrated transmitter IC capable of universal direct modulation for UHF AM, PM, or compound carriers. The transmitter may be used stand-alone for applications requiring not more than 100mW output power, or may be used to drive a final power amplifier. The maximum output level is 100mW, and is adjustable over a 25dB range by a single positive voltage. This low-cost IC implements differential amplifi- ers for the modulation inputs, 90 degree carrier phase shift network, carrier limiting amplifiers, two matched dou- bly-balanced mixers, variable gain summing amplifier for level control, and 100mW linear (class AB) output ampli- fier.  Single 5V Power Supply  100mW Output Power Into 50Ω  25dB Gain Control Range  Excellent Phase & Amplitude Balance  Digitally Controlled Stand-By Mode  800MHz to 1000MHz Operation RF2423 100mW Spread-Spectrum T ransmitter IC RF2423 PCBA Fully Assembled Evaluation Board Rev A3 001218 .010 .004 .065 .043 .244 .228 .050 .016 .010 .007 .157 .150 .393 .386 .018 .0141 .050 8 °MAX 0°MIN Package Style: SOP-16

Supply Voltage -0.5 to +7.5 V DC Power Down Voltage (VPD )V DD +0.4 V DC Input LO and RF Levels +6 dBm Operating Ambient T emperature -40 to +85 °C Storage Temperature -40 to +150 °C Parameter Specification Unit ConditionMin. Typ. Max. Carrier Input (LO IN) T=25° C, VDD =5.3V , VGC =5.3V Frequency Range 800 to 1000 MHz Power Level 0 to +6 dBm Input Impedance 55-j120 Ω 915MHz Modulation Input Frequency Range DC to 100 MHz Reference Voltage (VREF ) 2.0 to 3.0 V Modulation for 100mW Output Power (I & Q) VREF ±2 V Maximum Modulation (I & Q) V REF ±2.5 V Quadrature Phase Error ±3 ° Input Impedance 3000 Ω DC Offset (I & Q) 40 200 mV RF Output VDD =5.3V , VGC=5.3V , LO power=0dBm, LO frequency=915MHz, SSB, I/Q=2.0VP sine wave, VREF =3V Output Power +22 +22 dBm -15 -10 +5 dBm V GAIN =0V Output Impedance 50 Ω Output VSWR 2:1 Second Harmonic Output -45 dBc Other Harmonics Output <-20 dBc Sideband Suppression 25 35 dB Carrier Suppression 22 30 dB Modulation DC offset can be externally adjusted for optimum suppression. Carrier suppression is then typically better than 40dB. Output Level Control Control Range 25 dB Control Voltage 1 to 4 V Control Input Current <1.5 mA Standby Mode Turn On/Off Time <100 ns STANDBY Input Impedance >50 k Ω Power Down “ON” V CC V Threshold voltage; Part is turned “ON” Power Down “OFF” 0 V Threshold voltage; Part is turned “OFF” Power Supply Voltage 5 V Specifications 4.5 to 6.0 V Operating limits Current 60 110 170 mA Total, 100mW output power 50 mA Total, minimum output power 2 20 mA Standby mode 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).

Pin Function Description Interface Schematic 1G C Gain control of the RF amplifier. This pin can be used to control the out- put power over a 25dB range. Output power is the lowest when the control voltage is 1V or lower, and the highest when set to 4V or higher. When a fixed maximum output level is needed, it is recommended to connect this pin to VDD. 2 PHASE This pin adjusts the phase of the I/Q signals. However, the control is very sensitive and hard to control. Control voltage change for a few degrees adjustment is in the order of 10mV . Device to device and tem- perature variation are not characterized. Therefore it is not recom- mended to use this pin; leave it not connected. Do NOT connect it to ground. For compensating large errors in the I/Q signals supplied to the device or in control loops, this pin may prove useful. 3V D D 1 Power supply to all circuits except the RF output stages. It is recom- mended to put some RF decoupling on this pin, though it is not critical. An optional 0.1µF capacitor is required if no other low frequency bypass capacitor is nearby. 4G N D 2 Ground connection for the gain controlled RF amplifier. Keep traces physically short and connect immediately to ground plane for best per- formance. 5 LO IN Modulator LO input. A series 22nH inductor can be used for matching. This pin is NOT internally DC blocked. An external blocking capacitor must be provided if the pin is connected to a device with DC present. A DC path to ground (i.e. an inductor or resistor to ground) is, however, acceptable at this pin. If a blocking capacitor is required, a value of 33pF is recommended. 6G N D 1 Ground connection for the baseband, LO and mixer circuits. Keep traces physically short and connect immediately to ground plane for best performance. 7I R E F Reference voltage for the I mixer. This voltage should be the same as the DC voltage supplied to the I SIG pin. To obtain a carrier suppres- sion of better than 25dB it may be tuned ±0.15V (relative to the I SIG DC voltage). Without tuning, it will typically be better than 25dB. Input impedance of this pin is about 3kΩ . 8I S I G Baseband input to the I mixer. This pin is DC coupled. Maximum output power is obtained when the input signal has a peak to peak amplitude of 5V . The DC level supplied to this pin should be VDD2/2. Input imped- ance of this pin is about 3kΩ . 9Q S I G Baseband input to the Q mixer. This pin is DC coupled. Maximum out- put power is obtained when the input signal has a peak to peak ampli- tude of 5V . The DC level supplied to this pin should be VDD2/2. Input impedance of this pin is about 3kΩ .10 Q REF Reference voltage for the Q mixer. This voltage should be the same as the DC voltage supplied to the Q SIG pin. T o obtain a carrier suppres- sion of better than 25dB it may be tuned ±0.15V (relative to the Q SIG DC voltage). Without tuning it will typically be better than 25dB. Input impedance of this pin is about 3kΩ . 10 kΩ 5 kΩ GC PHASE 4 kΩ LO IN 1 kΩ 2 kΩ 2 kΩ I SIGI REF 1 kΩ 1 kΩ 2 kΩ 2 kΩ Q SIGQ REF 1 kΩ

Pin Function Description Interface Schematic 11 GND4 Ground connection for the RF driver and output stage. Keep traces physically short and connect immediately to ground plane for best per- formance. Having a good ground connection on this pin is extremely important due to the high RF levels in the circuits connected to this pin. 12 RF OUT 50Ω RF output. This pin is not internally DC blocked and an external blocking capacitor of 22pF is needed. 13 GND3 Ground connection for the RF driver and output stage. Keep traces physically short and connect immediately to ground plane for best per- formance. Having a good ground connection on this pin is extremely important due to the high RF levels in the circuits connected to this pin. 14 VDD3 Power supply for the RF output stage. A 33pF external bypass capaci- tor is required and an optional 0.1µF will be required if no other low fre- quency bypass capacitors are nearby. 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. Having good bypassing on this pin is especially important because of the high levels of RF signal on the circuits connected to this pin. 15 VDD2 Power supply for the RF driver stage. A 33pF external bypass capacitor is required and an optional 0.1µF will be required if no other low fre- quency bypass capacitors are near by. 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. Having good bypassing on this pin is especially important because of the high levels of RF signal on the circuits connected to this pin. 16 STANDBY Standby mode control. When this pin is 0V all circuits are turned off, and when this pin is VDD all circuits are operating. This is a high impedance input, internally connected to the gate of a few transistors. To minimize current consumption in power down mode, this pin should be as close to 0 V as possible, or even a little negative. T urn-on voltage of some parts of the circuit may be as low as 0.0 V . In order to maxi- mize output power this pin should be as close to VDD as possible dur- ing normal operation. RF OUT VDD

C Note 1 Note 1 100 nF C 22 nH CMOS R R C 100 nF VDD R C R 22 pF VREF 100 nF VDD VREF I INPUT LO INPUT GAIN CONTROL STANDBY RF OUTPUT Q INPUT POWER CONTROL Σ -45° +45° 33 pF SMD capacitor mounted as close to the package pin as possible, grounded through via to the ground plane with minimum inductance. The values of R and C depend on the lowest frequency of the baseband signal. NOTE 1: NOTE 2:

Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) 36 pF 100 nF 100 pFR2 Ω 36 pF P2-2 P2-5C5 100 nF 100 nF P2-1 P1-3 P1-4 22 nH Ω Ω P1-2 P1-1 Ω 36 pF POWER CONTROL Σ -45° +45° P2-4 LO IN RF OUT P2-4 P1-1 P1-3 IREF QREF QSIG1 P2-1 P2-2 GND PHASE LEVEL1 GND ISIG STBY VDD P1-2 P1-4 P2-4 P2-5

2423400 Rev -

1.25” x 1.25” Board Thickness 0.031”; Board Material FR-4