RF2670

RF2670 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/Gfc SiGe HBT Si CMOS 0-25 dB 0-20 dB -12-+12 17dB 6d B PD BW SEL2 BW SEL1 RSSI Q RSSI I VREF IN I+ IN I- DCFB I VCC2 DCFB Q IF OUT Q Q DATA VCC3 VCC1 IN Q+ IN Q- IF OUT I I DATA 5 8 VGC DC Bias RF2670 8MHZ DUAL BASEBAND AGC WITH PROGRAMMABLE LOW PASS FILTERING

• Digital Cordless Telephones  Secure Communication Links W i r e l e s sL A N s  Inventory Tracking  Wireless Security  Battery Powered Applications The RF2670 is a monolithic integrated circuit specifically designed for direct conversion to baseband QPSK receiv- ers. The part provides dual baseband amplifiers with a 70dB gain range (single pin analog input) and separate I and Q RSSI. On-chip programmable baseband filters are incorporated into each amplifier providing 1MHz, 2MHz, 4MHz, or 8MHz bandwidth with a 5-pole Bessel response. I and Q output are available in digital or analog form. The data comparators use a self generated DC ref- erence to track DC offsets in the received signal. The analog outputs have a 500mVpp swing with approxi- mately 1.7V DC offset. A 2.0V reference voltage is also available for A/D converters changing DC bias.  I/Q Baseband Receivers 1 0 d Bt o8 0 d BG a i nR a n g e  Digital and Analog Outputs  On-Chip Selectable IF Bandwidths  Reference Voltage for A/D Converter  2.7V to 3.6V Operation RF2670 8MHz Dual Baseband AGC with Programmable Low Pass Filtering RF2670PCBA Fully Assembled Eval Board. Rev A4 010820 .069 .053 .050 .016 8°MAX 0°MIN .010 .008 .157 .150 .244 .228 .344 .337 .012 .008 .025 .010 .004 .033 Package Style: SSOP-24

Supply Voltage -0.5 to +3.6 V DC Control Voltages -0.5 to +3.6 V DC Input RF Level +20 dBm Operating Ambient Temperature -40 to +85 °C Storage Temperature -40 to +150 °C Parameter Specification Unit ConditionMin. Typ. Max. Baseband Amplifiers T=25°C, VCC =3.0V Frequency Range 0.01 8 MHz Minimum frequency is dependent upon input blocking cap, DC feedback cap, and gain setting. Recommended components yields a minimum frequency of less than 10kHz. Voltage Gain 77 80 83 dB Noise Figure 5 dB At maximum gain setting 35 dB At minimum gain setting Input IP3 -65 dBm At maximum gain setting +2 dBm At minimum gain setting Output DC offset 0 25 mV Gain Control Range 65 70 dB Gain Control Voltage Range 1.2 2.0 V Gain Control Sensitivity -0.08 dB/mV VGA Output Voltage 500 mV PP VGA DC Output Voltage 1.7 V Output P1dB 1 1.64 V PP Driving a 5kΩ load RSSI Range 55 60 dB At maximum gain setting RSSI Output Voltage Compli- ance 0.5 to 2.4 V Maximum RSSI is 2.5V or V CC -0.3, which- ever is less. Input Impedance 1.5 2 2.5 k Ω Differential Integrated Filters Characteristics Five pole Bessel Five pole Bessel internal LPF . Three pole external LPF . Bandwidth 1, 2, 4, 8 MHz Selectable from 1MHz, 2MHz, 4MHz, and 8MHz. Passband Ripple 1 dB Group Delay 100 ns At 8MHz, increasing as bandwidth decreases. Ultimate Rejection 50 80 dB Data Amplifiers Voltage Gain 100 dB Bandwidth 8 MHz Rise and Fall Time 2 5 ns 5pF Load Logic High Output V CC -0.3V V Can sink/source 1mA and maintain these logic levels. Logic Low Output 0.3 V Can sink/source 1mA and maintain these logic levels. Hysteresis 40 mV Power Down Control Logical Controls “ON” V CC -0.3V V Voltage supplied to the input Logical Controls “OFF” 0.3 V Voltage supplied to the input Control Input Impedance >1 M Ω Turn on Time 10 13 ms With recommended DC feedback cap (270nF) 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).

Parameter Specification Unit ConditionMin. Typ. Max. Power Supply Voltage 2.7 3.0 3.6 V Current Consumption 13 17 mA V CC =3.0V; PD=High 1 µAV CC =3.0V; Sleep Mode, PD=Low

Pin Function Description Interface Schematic 1I N I - Complementary input for the in-phase IF channel. 2I N I + Input for the in-phase IF channel. 3 GND2 Ground for VCC2. 4 DCFB I DC feedback capacitor for in-phase channel.

5 VCC2 Power supply for VGA amplifier 3, differential to single-ended converter,

and post filter. 6 GND3 Ground for VCC3. 7I F O U T I Analog signal IF output for in-phase channel. 8 VCC3 Power supply for data amplifier. 9I D A T A Logic-level data output for the in-phase channel. This is a digital output signal obtained from the output of a Schmitt trigger. 10 RSSI I Received signal strength indicator for the in-phase channel. 11 PD Enable pin for the receiver circuits. PD>2.0V powers up all of the func- tions. PD<1.0V turns off all of the functions. 12 GND1 Ground for VCC1 for both the in-phase and quadrature channels. 13 BW SEL1 Bandwidth select logic input. Pin 13 and pin 14 provide a two bit control word for the setting of the IF bandwidth. See Table1. Additional filtering should be used at the amplifiers to precisely control the 3dB bandwidth of the system. See design information details about differential input fil- ters. 14 BW SEL2 See pin 13. 15 Q DATA Logic-level data output for the quadrature channel. This is a digital out- put signal obtained from the output of a Schmitt trigger. 16 RSSI Q Received signal strength indicator for the quadrature channel. 17 VREF Gain control reference voltage. 18 IF OUT Q Analog signal IF output for quadrature channel. 19 VGC Gain control voltage.

20 VCC1 Power supply for bias circuits and VGA amplifiers for both the in-phase

and quadrature channels. 21 DCFB Q DC feedback capacitor for quadrature channel. 22 GND1 Ground for VCC1 for both the in-phase and quadrature channels.

23 IN Q+ Plus input for quadrature channel

24 IN Q- Minus input for quadrature channel

Table 1: Bandwidth Selection Controls BWSEL1 BWSEL2 IF-3dB Frequency 00 1 M H z 01 2 M H z 10 4 M H z 11 8 M H z

Differential Filter Design Information Butterworth Response RS RS L L RL RL C 1 C 1bw 1 2--- 1012⋅⋅ C 2bw 1 2--- 1012⋅⋅ C 1bw 5.1672C 2bw; 15.4554 Lbw; 0.1377== = RS 125 RL; 1000 RS Differential LC Filter Component Values (Butterworth Response) 100 1000 10000 100000 Frequency Component Value C2 (pF) C1 (pF) L(µH)

Differential Filter Design Information (Cont.) Bessel Response RS RS L L RL RL C 1 C 1bw 1 2--- 1012⋅⋅ C 2bw 1 2--- 1012⋅⋅ C 1bw 2.9825C 2bw; 15.4697 Lbw; 0.0860== = RS 125 RL; 1000 RS Differential LC Filter Component Values (Bessel Response) 100 1000 10000 100000 Frequency Component Value C2 (pF) C1 (pF) L(µH)

Evaluation Board Schematic (Download Bill of Materialsfrom www.rfmd.com.) C26 10 nF C25 100 pF C24 10 nF C23 100 pF C22 10 nF C21 100 pF P3-1 IN I- IN I+ GND2 DCFB I VCC2 GND3 IF OUT I VCC3 I DATA RSSI I VI FE N GND1 IN Q- IN Q+ GND1 DCFB Q VCC1 VGC IF OUT Q VREF RSSI Q Q DATA BW SEL2 BW SEL1 100 nF 100 nF 1n F 10 µ H 220 pF 50 Ω µ stripJ1 II N 10 µ H DCFB I 220 nF VCC 50 Ω µ stripJ2 IF OUT I 50 Ω µ stripJ3 I DATA RSSI I C13 68 pF VI FE N 100 nF 100 nF 1n F 10 µ H 220 pF 50 Ω µ strip J4 QI N 10 µ H DCFB Q C10 220 nF VCC VGC 50 Ω µ strip IF OUT Q VREF C11 47 nF RSSI Q C12 68 pF 50 Ω µ strip Q DATA BW SEL2 BW SEL1 C27 10 µ F 2670400- P5-1 BW SEL2 GND P5-3 BW SEL1 P4-1 DCFB Q GND P4-3 VREF VCC GND P3-3 VGC P2-1 RSSI Q GND P2-3 RSSI I P1-1 VI FE N GND P1-3 DCFB I L1-L4 and C1-C4 make two LPFs. The fc of the RF2670 is variable; therefore the L and C components must be variable. The following table gives recommended component values ("std" indicates standard eval board value). Desired BW BW1, BW2 C1, C4 (pF)C2, C3 (pF)L1-L4 (µ H) 700 kHz

1.4 MHz

2.8 MHz

7.0 MHz

220 (std) 100 1800 1000 (std) 470 180 4.7 2.2

Board Size 3.0” x 2.0”

RF2670 IF Bandwidth Response -35.0 -25.0 -15.0 -5.0 5.0 15.0 25.0 35.0 45.0 55.0 65.0 0.1 1.0 10.0 100.0 IF Frequency (MHz) Gain (dB) BW_SEL (0-0) BW_SEL (0-1) BW_SEL (1-0) BW_SEL (1-1)

-80.0 -70.0 -60.0 -50.0 -40.0 -30.0 -20.0 -10.0 0.0 10.0 Voltage Gain (dB) IP3 (dB) -40°C +25°C +100°C Noise Figure versus Voltage Gain (Non-Matched Input Z) 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 Voltage Gain (dB) Noise Figure (dB) -40°C +25°C +100°C Voltage Gain versus Gain Control Voltage 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 Gain Control Voltage (V) Voltage Gain (dB) -40°C +25°C +100°C