MAX2620 19-1248 Rev 2 2/02 10MHz to 1050MHz Integrated RF Oscillator with Buffered Outputs General Description Features The MAX2620 combines a low-noise oscillator with two Low-Phase-Noise Oscillator: -110dBc/Hz output buffers in a low-cost, plastic surface-mount, (25kHz offset from carrier) Attainable ultra-small MAX package. This device integrates func- Operates from Single +2.7V to +5.25V Supply tions typically achieved with discrete components. The oscillator exhibits low-phase noise when properly Low-Cost Silicon Bipolar Design mated with an external varactor-tuned resonant tank Two Output Buffers Provide Load Isolation circuit. Two buffered outputs are provided for driving mixers or prescalers. The buffers provide load isolation Insensitive to Supply Variations to the oscillator and prevent frequency pulling due to Low, 27mW Power Consumption (V = 3.0V) CC load-impedance changes. Power consumption is typi- Low-Current Shutdown Mode: 0.1A (typ) cally just 27mW in operating mode (V = 3.0V), and CC drops to less than 0.3W in standby mode. The MAX2620 operates from a single +2.7V to +5.25V supply. Applications Ordering Information Analog Cellular Phones PART TEMP RANGE PIN-PACKAGE Digital Cellular Phones MAX2620EUA -40C to +85C 8 MAX MAX2620E/D -40C to +85C Dice* 900MHz Cordless Phones *Dice are tested at T = +25C, DC parameters only. A 900MHz ISM-Band Applications Land Mobile Radio Pin Configuration appears at end of data sheet. Narrowband PCS (NPCS) Typical Operating Circuit V V CC CC 10 1000pF 10nH 1000pF 1.5pF 1 V 1 OUT 8 CC OUT TO MIXER C17 C5 MAX2620 1.5pF 1.5pF V CC TANK 2 7 V TUNE V 2 CC C3 1k 0.1 F 2.7pF 3 FDBK 6 GND CERAMIC C6 RESONATOR 1000pF D1 C4 4 SHDN BIAS OUT 5 L1 ALPHA 1pF OUT TO SYNTHESIZER SUPPLY SMV1204-34 51 SHDN V CC 1000pF 900MHz BAND OSCILLATOR Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE10MHz to 1050MHz Integrated RF Oscillator with Buffered Outputs ABSOLUTE MAXIMUM RATINGS V 1, V 2 to GND .................................................-0.3V to +6V Operating Temperature Range CC CC TANK, SHDN to GND .................................-0.3V to (V + 0.3V) MAX2620EUA .................................................-40C to +85C CC OUT, OUT to GND...........................(V - 0.6V) to (V + 0.3V) Junction Temperature......................................................+150C CC CC FDBK to GND ..................................(V - 2.0V) to (V + 0.3V) Storage Temperature Range .............................-65C to +165C CC CC Continuous Power Dissipation (T = +70C) Lead Temperature (soldering, 10s) .................................+300C A MAX (derate 5.7mW/C above +70C) .....................457mW Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (V 1, V 2 = +2.7V to +5.25V, FDBK = open, TANK = open, OUT and OUT connected to V through 50 , SHDN = 2V, CC CC CC T = -40C to +85C, unless otherwise noted. Typical values measured at V 1 = V 2 = 3.0V, T = +25C.) (Note 1) A CC CC A PARAMETER CONDITIONS MIN TYP MAX UNITS Supply Current 9.0 12.5 mA Shutdown Current SHDN = 0.6V 0.1 2 A Shutdown Input Voltage High 2.0 V Shutdown Input Voltage Low 0.6 V Shutdown Bias Current High SHDN = 2.0V 5.5 20 A Shutdown Bias Current Low SHDN = 0.6V 0.5 A Note 1: Specifications are production tested and guaranteed at T = +25C and T = +85C. Specifications are guaranteed by A A design and characterization at T = -40C. A AC ELECTRICAL CHARACTERISTICS (Test Circuit of Figure 1, V = +3.0V, SHDN = V , Z = Z = 50, P = -20dBm (50 ), f = 900MHz, CC CC LOAD SOURCE IN TEST T = +25C, unless otherwise noted.) A PARAMETER CONDITIONS MIN TYP MAX UNITS Frequency Range T = -40C to +85C (Note 2) 10 1050 MHz A Reverse Isolation 50 dB OUT or OUT to TANK OUT, OUT driven at P = -20dBm Output Isolation OUT to OUT 33 dB Note 2: Guaranteed by design and characterization at 10MHz, 650MHz, 900MHz, and 1050MHz. Over this frequency range, the magnitude of the negative real impedance measured at TANK is greater than one-tenth the magnitude of the reactive impedances at TANK. This implies proper oscillator start-up when using an external resonator tank circuit with Q > 10. C3 and C4 must be tuned for operation at the desired frequency. 2 MAX2620