MAX9987/MAX9988 19-2416 Rev 2 3/04 +14dBm to +20dBm LO Buffers/Splitters with 1dB Variation General Description Features The MAX9987 and MAX9988 LO buffers/splitters each 1dB Output Power Variation integrate a passive two-way power splitter with high- +14dBm to +20dBm Adjustable Output Power isolation input and output buffer amplifiers. These buffers are designed to provide the high output Two-Way Power Splitting (+14dBm to +20dBm) necessary to drive the LO inputs 40dB Reverse Isolation of high-linearity passive mixers, while offering 40dB reverse isolation to prevent LO pulling. The MAX9987 is More than 30dB Output-to-Output Isolation internally matched for the cellular/GSM bands, and the Low Output Noise: -170dBc/Hz at +17dBm MAX9988 is matched for the DCS/PCS/UMTS bands. The typical application circuit provides a nominal 160mA Supply Current at +17dBm +17dBm output power with 1dB variation over supply, Isolated PLL Output (+3dBm) temperature, and input power. With two optional resis- tors, the output power can be precision set from +14dBm to +20dBm. The devices offer more than 30dB output-to-output port isolation, and are offered in 5mm 5mm 20-pin thin QFN packages with exposed paddle. Applications Ordering Information Cellular/GSM/DCS/PCS/UMTS Base Station TEMP PIN- FREQUENCY PART Tx/Rx LO Drive RANGE PACKAGE RANGE Base Station Main and Diversity Channels 20 Thin 700MHz to MAX9987ETP-T -40C to 85C Coherent Receivers QFN-EP* 1100MHz ISM Wireless LAN 20 Thin 1500MHz to MAX9988ETP-T -40C to 85C QFN-EP* 2200MHz Wireless Local Loop *EP = Exposed paddle. Local Multipoint Distribution Service Point-to-Point Systems Typical Operating Circuit and Block Diagram RF INPUT OUTPUT AMP (1) PLL BUFFER (1) MAX9987 TO PLL OUTPLL OUT1 MAX9988 (+3dBm) IF OUTPUT PRESCALER (+17dBm) (1) IN RF INPUT (+7dBm) INPUT AMP (2) RF LO PASSIVE TWO-WAY POWER SPLITTER OUT2 IF OUTPUT (+17dBm) (2) BIAS OUTPUT AMP (2) BIASIN BIASOUT BIAS CONTROL NETWORK 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.+14dBm to +20dBm LO Buffers/Splitters with 1dB Variation ABSOLUTE MAXIMUM RATINGS VCC1, VCC2, VCC3, Continuous Power Dissipation (T = +70C) A VCCREF to GND.................................................-0.3V to +6.0V 5mm 5mm 20-Pin Thin QFN (derate 20mW/C IN to GND...................................................-0.3V to (V + 0.3V) above +70C).............................................................1600mW CC OUT1, OUT2, ....................................................................................50C/W JA OUTPLL to GND......................................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C CC REF to GND ......................................................Source/Sink 5mA Operating Temperature Range ...........................-40C to +85C INBIAS, OUTBIAS, to GND..................................-0.3V to +0.75V Storage Temperature Range .............................-65C to +150C PLLBIAS ......................................................................Sink 25mA Lead Temperature (soldering, 10s) .................................+300C RF Input Power...............................................................+20dBm 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 CHARACTERISTICSMAX9987 (Typical Application Circuit, V = 4.75V to 5.25V, input and outputs terminated in 50, T = -40C to +85C. Typical specifications CC A are for V = 5.0V and T = +25C.) (Note 1) CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V 4.75 5.00 5.25 V CC Low power setting 110 (see Table 1 for resistor values) Nominal power setting Supply Current I 139 155 171 mA CC (R , R , R , and R not installed) 1 2 4 5 High power setting 221 (see Table 1 for resistor values) DC ELECTRICAL CHARACTERISTICSMAX9988 (Typical Application Circuit, V = 4.75V to 5.25V, input and outputs terminated in 50, T = -40C to +85C. Typical specifications CC A are for V = 5.0V and T = +25C.) (Note 1) CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V 4.75 5.00 5.25 V CC Low power setting 120 (see Table 1 for resistor values) Nominal power setting Supply Current I 150 162 175 mA CC (R , R , R , and R not installed) 1 2 4 5 High power setting 229 (see Table 1 for resistor values) 2 MAX9987/MAX9988