Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz DESCRIPTION SA620 FEATURES The SA620 is a combined RF amplifier, VCO with tracking bandpass filter and mixer designed for high-performance low-power communication systems from 800-1200MHz. The low-noise preamplifier has a 1.6dB noise figure at 900MHz with 11.5dB gain and an IP3 intercept of -3dBm at the input. The gain is stabilized by on-chip compensation to vary less than ±0.2dB over -40 to +85°C temperature range. The wide-dynamic-range mixer has an 9dB noise figure and IP3 of –6dBm at the input at 900MHz. An external LO can be used in place of the internal VCO for improved mixer input IP3 and a 3mA reduction in current. The chip incorporates a through-mode option so the RF amplifier can be disabled and replaced by an attenuator (S21 = –7.5dB). This is useful for improving the overall dynamic range of the receiver when in an overload situation. The nominal current drawn from a single 3V supply is 10.4mA and 7.2mA in the thru-mode. Additionally, the VCO and Mixer can be powered down to further reduce the supply current to 1.2mA. • Low current consumption: 10.4mA nominal, PIN CONFIGURATION DK Package 7.2mA with thru-mode activated 20 VCC LNA ENABLE 1 • Outstanding noise figure: 1.6dB for the amplifier and 9dB for the mixer at 900MHz • Excellent gain stability versus temperature and supply voltage • Switchable overload capability • Independent LNA, mixer and VCO power LNA GND 2 19 LNA GND LNA IN 3 18 LNA OUT LNA GND 4 17 LNA BIAS 5 16 MIXER IN LNA GND OSC GND 6 7 14 MIXER BYPASS OSC PWRDN 8 13 MIXER OUT down capability • Internal VCO automatic leveling loop • Monotonic VCO frequency vs control 15 MIXER GND MIXER PWRDN OSC1 9 12 OSC GND OSC2 10 11 VCO OUT voltage APPLICATIONS • 900MHz cellular front-end • 900MHz cordless front-end • Spread spectrum receivers • RF data links • UHF frequency conversion • Portable radio ORDERING INFORMATION DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG # -40 to +85°C SA620DK 1563 20-Pin Plastic Shrink Small Outline Package (Surface-mount, SSOP) BLOCK DIAGRAM VCC LNA GND LNA OUT LNA BIAS 20 19 18 17 MIXER IN MIXER GND MIXER BYPASS MIXER OUT OSC GND VCO OUT 16 15 14 13 12 11 RF IF LO 1 LNA ENABLE December 15, 1993 2 LNA GND 3 LNA IN TRACKING BANDPASS FILTER AUTOMATIC LEVELING LOOP LNA 4 LNA GND 5 LNA GND VCO 6 7 8 9 OSC GND MIXER PWRDN OSC PWRDN OSC1 2 10 OSC2 853-1725 11658 Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 ABSOLUTE MAXIMUM RATINGS SYMBOL PARAMETER voltage1 VCC Supply VIN Voltage applied to any other pin PD Power dissipation, TA = 25°C (still 20-Pin Plastic SSOP RATING UNITS -0.3 to +6 V -0.3 to (VCC + 0.3) V 980 mW air)2 TJMAX Maximum operating junction temperature 150 °C PMAX Maximum power input/output +20 dBm TSTG Storage temperature range –65 to +150 °C NOTE: 1. Transients exceeding 8V on VCC pin may damage product. 2. Maximum dissipation is determined by the operating ambient temperature and the thermal resistance, θJA: 20-Pin SSOP = 110°C/W RECOMMENDED OPERATING CONDITIONS SYMBOL VCC PARAMETER RATING UNITS Supply voltage 2.7 to 5.5 V TA Operating ambient temperature range -40 to +85 °C TJ Operating junction temperature -40 to +105 °C DC ELECTRICAL CHARACTERISTICS VCC = +3V, TA = 25°C; unless otherwise stated. SYMBOL PARAMETER TEST CONDITIONS LIMITS MIN ICC Supply current TYP UNITS MAX LNA enable input high 10.4 mA LNA enable input low 7.2 mA VCO power-down input low 7.4 mA Mixer power-down input low 7.4 mA Full chip power-down 1.2 mA voltageNO TAG VT Enable logic threshold 1.2 1.5 1.8 V VIH Logic 1 level RF amp on VIL Logic 0 level RF amp off 2.0 VCC V –0.3 0.8 V IIL Enable input current Enable = 0.4V -1 IIH Enable input current Enable = 2.4V -1 0 1 µA 0 1 µA VLNA–IN LNA input bias voltage Enable = 2.4V 0.78 V VLNA–OU LNA output bias voltage Enable = 2.4V 2.1 V LNA bias voltage Enable = 2.4V 2.1 V 0.94 V T VB VMX–IN Mixer RF input bias voltage NOTE: 1. The ENABLE input must be connected to a valid logic level for proper operation of the SA620 LNA. December 15, 1993 3 Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 AC ELECTRICAL CHARACTERISTICS VCC = +3V, TA = 25°C; Enable = +3V; unless otherwise stated. SYMBOL PARAMETER S21 Amplifier gain S21 Amplifier gain in through mode TEST CONDITIONS LIMITS UNITS -3σ TYP +3σ 900MHz 10 11.5 13 dB Enable = 0.4V, 900MHz -9 -7.5 -6 dB ∆S21/∆T Gain temperature sensitivity in pwr-dwn mode 900MHz -0.014 dB/°C ∆S21/∆T Gain temperature sensitivity enabled 900MHz 0.003 dB/°C ∆S21/∆f Gain frequency variation 800MHz - 1.2GHz 0.01 dB/MHz 900MHz -20 dB 900MHz -10 dB S12 S11 S22 Amplifier reverse isolation Amplifier input match1 900MHz -12 dB Amplifier input 1dB gain compression 900MHz -16 dBm IP3 Amplifier input third order intercept 900MHz -4.5 -3 -1.5 dBm NF Amplifier noise figure 900MHz 1.3 1.6 1.9 dB tON Amplifier turn-on time (Enable Lo → Hi) tOFF Amplifier turn-off time (Enable Hi → Lo) P-1dB Amplifier output match1 See Figure 1 50 µs See Figure 1 5 µs VGC Mixer voltage conversion gain: RP = RL = 1kΩ, fS = 0.9GHz, fLO = 0.8GHz, fIF = 100MHz PGC Mixer power conversion gain: RP = RL = 1kΩ, fS = 0.9GHz, fLO = 0.8GHz, fIF = 100MHz S11M Mixer input match1 900MHz NFM Mixer SSB noise figure 900MHz P-1dB Mixer input 1dB gain compression IP3M Mixer input third order intercept IP2INT Mixer input second order intercept 900MHz 12 PRFM-IF Mixer RF feedthrough 900MHz -20 dB PLO-IF LO feedthrough to IF 900MHz -25 dBm PLO-RFM LO to mixer input feedthrough 900MHz -30 dBm PLO-RF LO to LNA input feedthrough 900MHz -45 dBm VCO buffer out 900MHz -16 dBm PVCO 16 17.5 dB 1.5 3 4.5 dB -10 7.5 900MHz f2–f1 = 1MHz, 900MHz 9 VCO phase noise Offset = 60kHz NOTE: 1. Simple L/C elements are needed to achieve specified return loss. 4 dB 10.5 -13 -7.5 -6 300 (min) VCO frequency range December 15, 1993 14.5 dBm -4.5 dBm dBm 1200 (max) -105 dB MHz dBc/Hz Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 LNA ENABLE C22 C23 1µF C1 100pF LNA IN 4.7nH 535 mils R6 R = 9k x (VCC – 1) 0.44µF/(VCC–1) L1 56nH C19 100pF VCC C21 0.1µF C2 1.8pF C20 w = 15 mils L = 260 mils C3 0.1µF C4 C5 3.9pF 10µF VCC L3 2.7nH C6 GND L2 2.7nH 100pF D1 SMV 1204 - 099 Alpha Industries V_CONTROL (0 to VCC) LNA OUT C18 2.2pF w = 15 mils L = 260 mils 1 2 3 4 5 6 7 8 9 10 LNA ENABLE LNA GND LNA IN LNA GND LNA GND Vcc LNA GND LNA OUT LNA BIAS MIXER IN MIXER GND MIXER BYPASS MIXER OUT OSC GND VCO OUT OSC GND MIXER PD OSC PD OSC1 OSC2 20 19 18 17 16 15 14 13 12 11 C16 5.6pF 4.7nH 535 mils C13 C14 1-5pF VCC 12pF C15 0.1µF L4 150nH C9 100pF 4.7nH 535 mils R2 100pF w = 15 mils L = 160 mils SA620 VCO OUT (50Ω) MIXER IN C17 100pF R3 22Ω MIXER OUT (1kΩ, 83MHz) C10 100pF 10kΩ R1 10kΩ C7 3.3pF 4.7nH 535 mils C11 1000pF R4 1kΩ VCC C12 10pF MIXER OUT (50Ω, 83MHz) R5 51Ω C8 0.1µF Figure 1. A Complete LNA, Mixer and VCO CIRCUIT TECHNOLOGY LNA Impedance Match: Intrinsic return loss at the input and output ports is 7dB and 9dB, respectively. With no external matching, the associated LNA gain is ≈10dB and the noise figure is ≈1.4dB. However, the return loss can be improved at 900MHz using suggested L/C elements (Figure NO TAG) as the LNA is unconditionally stable. Noise Match: The LNA achieves 1.6dB noise figure at 900MHz when S11 = -10dB. Further improvements in S11 will slightly increase the NF and S21. Thru-Mode: A series switch can be activated to feed RF signals from LNA input to output with an attenuator (S21 = –7.5dB). As a result, the power handling is greatly improved and current consumption is decreased by 3.2mA as well. However, if this mode is not required, C23 and R6 can be deleted. Temperature Compensation: The LNA has a built-in temperature compensation scheme to reduce the gain drift to 0.003dB/°C from –40°C to +85°C. Supply Voltage Compensation: Unique circuitry provides gain stabilization over wide supply voltage range. The gain changes no more than 0.5dB when VCC increases from 3V to 5V. December 15, 1993 Mixer Input Match: The mixer is configured for maximum gain and best noise figure. The user needs to supply L/C elements to achieve this performance. Mixer Bypass: To optimize the IP3 of the mixer input, one must adjust the value of C14 for the given board layout. The value typically lies between 1 and 5pF. Once a value if selected, a fixed capacitor can be used. Further improvements in mixer IP3 can be achieved by inserting a resistive loss at the mixer input, at the expense of system gain and noise figure. Tracking Bandpass Filter: At the LO input port of the mixer there is a second-order bandpass filter (approx. 50MHz bandwidth) which will track the VCO center frequency. The result is the elimination of low frequency noise injected into the mixer LO port without the need for an external LO filter. Power Down: The mixer can be disabled by connecting Pin 7 to ground. If a Schottky diode is connected between Pin 1 (cathode) and Pin 7 (anode), the LNA disable signal will control both LNA and mixer simultaneously When the mixer is disabled, 3mA is saved. Test Port: Resistor R5 can be substituted with an external test port of 50Ω input impedance. Since R5 and MIXER OUT have 5 the same output power, the result is a direct power gain measurement. VCO Automatic Leveling Loop: An on-chip detector and loop amplifier will adjust VCO bias current to regulate the VCO amplitude regardless of the Q-factor (>10) of the resonator and varactor diode. However, the real current reduction will not occur until the VCO frequency falls below 500MHz. For a typical resonator the steady-state current is 3mA at 800MHz. Buffered VCO Output: The VCO OUT (Pin 11) signal can drive an external prescaler directly (see also the Philips SA7025 low voltage, fractional-N synthesizer). The extracted signal levels need to be limited to –16dBm or less to maintain mixer IIP3. Phase Noise: If close-in phase noise is not critical, or if an external synthesizer is used, C4 (Pin 8) can be decreased to a lower value. Power-Down: The VCO can be disabled by connecting Pin 8 to ground. If a Schottky diode is connected between Pin 1 (cathode) and Pin 8 (anode), the LNA disable signal will control both LNA and VCO simultaneously. When the VCO is disabled, 3mA is saved. Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS CH1 S11 1 U FS 4: 30.707 Ω -24.89 Ω 5.86 pF 1100.000 000 MHz 1: 2: 3: START CH1 S22 800.000 000 1 U MHz FS STOP 4: 39.811 Ω 1200.000 000 -22.93 Ω 33.184 Ω -39.105 Ω 800 MHz 31.879 Ω -33.66 Ω 900 MHz 30.594 Ω -28.695 Ω 1 GHz MHz 6.31 pF 1100.000 000 MHz 1: 2: 3: START 800.000 000 MHz STOP 1200.000 000 Figure 2. LNA Input and Output Match (at Device Pin) December 15, 1993 6 MHz 48.164 Ω -35.754 Ω 800 MHz 44.574 Ω -31.246 Ω 900 MHz 42.068 Ω -25.799 Ω 1 GHz Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) CH1 S21 4 U FS 4: -60.419 ° 2.7788 U 1100.000 000 MHz 1: 3.8929U -2.5227 ° 800 MHz 2: 3.3016U -22.365 ° 900 MHz 3.0718U -41.955 ° 1 GHz 3: CH1 START 800.000 000 S12 100 mU FS MHz STOP 4: 1200.000 000 MHz 92.09 mU -82.944 ° 1100.000 000 MHz 1: 77.911 mU -41.727 ° 800 MHz 2: 84.28 mU -55.909 ° 900 MHz 89.053 mU -70.55 ° 1 GHz 3: START 800.000 000 MHz STOP 1200.000 000 MHz Figure 3. LNA Transmission and Isolation Characteristics (at Device Pin) December 15, 1993 7 Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) CH1 S11 1 U FS 4: 8.7959Ω 12.241Ω 1.7711 nH 1100.000 000 MHz 1: 2: 3: START 800.000 000 MHz STOP Figure 4. Mixer RF Input Match (at Device Pin) December 15, 1993 8 1200.000 000 MHz 7.2375 Ω 5.1895 Ω 800 MHz 7.8293 Ω 7.6104 Ω 900 MHz 8.1147 Ω 9.9258 Ω 1 GHz Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) LNA Gain (S21) In Through Mode vs. Frequency (VCC = 3V) CH1 S21 log MAG Mixer RF Input Match vs. Frequency (VCC = 3V) CH1 S11 1 dB/ REF -5 dB log MAG 2 dB/ REF -5 dB -40°C 25°C 85°C -40°C 25°C 85°C START 800.000 000 MHz START 800.000 000 MHz STOP 1 200. 000 000 MHz LNA Gain (S21) vs. Frequency (VCC = 3V) CH1 S21 log MAG STOP 1 200. 000 000 MHz LNA Isolation (S12) vs. Frequency (VCC = 3V) CH1 S12 1 dB/ REF 10 dB log MAG 5 dB/ REF -10 dB 85°C 25°C -40°C -40°C 25°C 85°C START 800.000 000 MHz CH1 S11 START 800.000 000 MHz STOP 1 200. 000 000 MHz LNA Input Match (S11) vs. Frequency (VCC = 3V) log MAG STOP 1 200. 000 000 MHz LNA Output Match (S22) vs. Frequency (VCC = 3V) CH1 S22 1 dB/ REF -10 dB log MAG 3 dB/ REF -10 dB -40°C 25°C 85°C -40°C 25°C 85°C START 800.000 000 MHz December 15, 1993 START 800.000 000 MHz STOP 1 200. 000 000 MHz 9 STOP 1 200. 000 000 MHz Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) LNA Gain (Enabled) vs. Supply Voltage LNA IP3 (Enabled) vs. Supply Voltage 14.00 TEMPERATURE (°C) 4.00 2.00 11.00 25 85 8.00 LNA IP3 (dB) LNA GAIN (dB) -40 0.00 -2.00 -4.00 -6.00 5.00 -8.00 2.5 3 3.5 4 4.5 5 5.5 -10.00 VCC (V) 2.5 LNA Gain (Disabled) vs. Supply Voltage 3.5 4 VCC (V) 4.5 5 5.5 LNA Noise Figure (Enabled) vs. Supply Voltage 0.00 2.50 TEMPERATURE (°C) -40 -5.00 25 85 -10.00 2.00 LNA NF (dB) LNA GAIN (dB) 3 1.50 1.00 0.50 -15.00 2.5 3 3.5 4 4.5 5 0.00 5.5 2.5 VCC (V) 3.5 4 4.5 5 5.5 VCC (V) Mixer Power Gain vs. Supply Voltage Mixer Noise Figure vs. Supply Voltage TEMPERATURE (°C) 3.5 MIXER GAIN (dB) 3 3.0 -40 2.5 25 2.0 85 12.0 1.5 1.0 MIXER NF (dB) 11.0 10.0 9.0 8.0 0.5 7.0 0.0 2.5 3 3.5 4 4.5 5 5.5 6.0 VCC (V) 2.5 LO to RF In Leakage vs. Supply Voltage 4 VCC (V) 4.5 5 5.5 -30 -41 -31 TEMPERATURE (°C) -42 -40 -43 25 -44 -45 85 -46 -47 -48 -49 LO TO MIXER IN (dBm) LO TO MIXER IN (dBm) 3.5 LO to Mixer In Leakage vs. Supply Voltage -40 -50 3 -32 -33 -34 -35 -36 -37 -38 -39 2.5 3 December 15, 1993 3.5 4 VCC (V) 4.5 5 -40 5.5 10 2.5 3 3.5 4 VCC (V) 4.5 5 5.5 Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz SA620 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Mixer RF Feedthrough Leakage vs. Supply Voltage LO to IF Leakage vs. Supply Voltage -15 -25 -40 -28 -29 25 -30 85 -31 -32 -33 -17 RF FEEDTHROUGH (dB) -27 LO to IF (dBm) -16 TEMPERATURE (°C) -26 -18 -19 -20 -21 -22 -23 -24 -34 -25 -35 2.5 3 3.5 4 VCC (V) 4.5 5 2.5 5.5 3 3.5 4 VCC (V) 4.5 VCO Output Power vs. Supply Voltage -10 -11 -12 TEMPERATURE (°C) VCO OUT (dBm) -13 -14 -40 -15 25 -16 85 -17 -18 -19 -20 2.5 December 15, 1993 3 3.5 4 VCC (V) 11 4.5 5 5.5 5 5.5 Philips Semiconductors RF Communications Products Product specification Low voltage LNA, mixer and VCO — 1GHz December 15, 1993 12 SA620