19-1185; Rev 2; 5/97 KIT ATION EVALU E L B AVAILA 3.6V, 1W RF Power Transistors for 900MHz Applications ________________________Applications ____________________________Features ♦ Low Voltage: Operates from 1 Li-Ion or 3 NiCd/NiMH Batteries ♦ DC-to-Microwave Operating Range ♦ 1W Output Power at 900MHz ♦ On-Chip Diode for Accurate Biasing (MAX2602) ♦ Low-Cost Silicon Bipolar Technology ♦ Does Not Require Negative Bias or Supply Switch ♦ High Efficiency: 58% ______________Ordering Information TEMP. RANGE PIN-PACKAGE MAX2601ESA -40°C to +85°C 8 PSOPII MAX2602ESA MAX2602E/D -40°C to +85°C -40°C to +85°C 8 PSOPII Dice* PART *Dice are specified at TA = +25°C, DC parameters only. _________________Pin Configurations Narrow-Band PCS (NPCS) 915MHz ISM Transmitters TOP VIEW Microcellular GSM (Power Class 5) AMPS Cellular Phones C 1 8 C C 1 8 C E 2 7 E E 2 7 E Two-Way Paging E 3 6 E BIAS 3 6 E CDPD Modems B 4 5 B B 4 5 B Digital Cellular Phones Land Mobile Radios MAX2601 MAX2602 PSOPII PSOPII Typical Application Circuit appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 408-737-7600 ext. 3468. MAX2601/MAX2602 _______________General Description The MAX2601/MAX2602 are RF power transistors optimized for use in portable cellular and wireless equipment that operates from three NiCd/NiMH cells or one Li-Ion cell. These transistors deliver 1W of RF power from a 3.6V supply with efficiency of 58% when biased for constant-envelope applications (e.g., FM or FSK). For NADC (IS-54) operation, they deliver 29dBm with -28dBc ACPR from a 4.8V supply. The MAX2601 is a high-performance silicon bipolar RF power transistor. The MAX2602 includes a highperformance silicon bipolar RF power transistor, and a biasing diode that matches the thermal and process characteristics of the power transistor. This diode is used to create a bias network that accurately controls the power transistor’s collector current as the temperature changes. The MAX2601/MAX2602 can be used as the final stage in a discrete or module power amplifier. Silicon bipolar technology eliminates the need for voltage inverters and sequencing circuitry, as required by GaAsFET power amplifiers. Furthermore, a drain switch is not required to turn off the MAX2601/MAX2602. This increases operating time in two ways: it allows lower system end-of-life battery voltage, and it eliminates the wasted power from a drain-switch device. The MAX2601/MAX2602 are available in thermally enhanced, 8-pin SO packages, which are screened to the extended temperature range (-40°C to +85°C). The MAX2602 is also available in die form. MAX2601/MAX2602 3.6V, 1W RF Power Transistors for 900MHz Applications ABSOLUTE MAXIMUM RATINGS Collector-Emitter Voltage, Shorted Base (VCES) ....................17V Emitter Base Reverse Voltage (VEBO)...................................2.3V BIAS Diode Reverse Breakdown Voltage (MAX2602) ..........2.3V Average Collector Current (IC)........................................1200mA Continuous Power Dissipation (TA = +70°C) PSOPII (derate 80mW/°C above +70°C) (Note 1) ..........6.4W Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +165°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10sec) .............................+300°C Note 1: Backside slug must be properly soldered to ground plane (see Slug Layout Techniques section). 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 (TA = TMIN to TMAX, unless otherwise noted.) PARAMETER Collector-Emitter Breakdown Voltage SYMBOL BVCEO BVCES CONDITIONS IC < 100µA MIN Open base 15 Shorted base 15 TYP MAX UNITS V Collector-Emitter Sustaining Voltage LVCEO IC = 200mA 5.0 V Collector-Base Breakdown Voltage BVCBO IC < 100µA, emitter open 15 V 100 DC Current Gain hFE IC = 250mA, VCE = 3V Collector Cutoff Current ICES VCE = 6V, VBE = 0V 0.05 Output Capacitance COB VCB = 3V, IE = 0mA, f = 1MHz 9.6 1.5 µA pF AC ELECTRICAL CHARACTERISTICS (Test Circuit of Figure 1, VCC = 3.6V, VBB = 0.750V, ZLOAD = ZSOURCE = 50Ω, POUT = 30dBm, f = 836MHz, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL Frequency Range f Base Current IB Harmonics 2fo, 3fo Stability under Continuous Load Mismatch Conditions Two-Tone IMR Noise Figure VCC = 3.6V, POUT = 30dBm MIN TYP DC MAX UNITS 1 GHz 4.2 mA -43 dBc dBc VCC = 3.0V, POUT = 29dBm -42 POUT = 30dBm 11.6 dB No modulation 58 % VCC = 5.5V, all angles (Note 3) 8:1 POUT = +30dBm total power, f1 = 835MHz, f2 = 836MHz -16 IM5 NF VBB = 0.9V 3.3 Power Gain Collector Efficiency CONDITIONS (Note 2) η VSWR IM3 -25 dBc dB Note 2: Guaranteed by design. Note 3: Under these conditions: a) no spurious oscillations shall be observed at collector greater than -60dBc; b) no parametric degradation is observable when mismatch is removed; and c) no current draw in excess of the package dissipation capability is observed. 2 _______________________________________________________________________________________ 3.6V, 1W RF Power Transistors for 900MHz Applications VBB = 1.00V 30 VBB = 0.95V 0.6 VBB = 0.90V 0.4 POUT 29 IM3 25 POUT IM3 15 IM5 5 28 0.2 POUT, IM3, AND IM5 ARE RMS COMPOSITE TWO-TONE POWER LEVELS MAX2601-03 MAX2601-02 35 POUT, IM3, IM5 (dBm) POUT, IM3, AND IM5 ARE RMS COMPOSITE TWO-TONE POWER LEVELS POUT (dBm) ICC (A) 31 MAX2601-01 1.0 0.8 TWO-TONE OUTPUT POWER, IM3, IM5 vs. INPUT POWER TWO-TONE OUTPUT POWER AND IM3 vs. COLLECTOR CURRENT COLLECTOR CURRENT VBB = 0.85V VBB = 0.80V 0 1 2 3 4 5 6 0.5 0.4 0.6 0.7 10 5 0.8 15 20 25 VCE (V) ICC (A) INPUT POWER (dBm) TWO-TONE OUTPUT POWER, IM3, IM5 vs. INPUT POWER (f = 433MHz) ACPR vs. OUTPUT POWER (IS-54 π/4 DQPSK MODULATION, VBB = 0.85V) COLLECTOR EFFICIENCY vs. OUTPUT POWER (IS-54 π/4 DQPSK MODULATION, VBB = 0.85V) 3.0V -22 60 ACPR (dBc) 15 IM3 IM5 EFFICIENCY (%) -26 POUT, IM3, AND IM5 ARE RMS COMPOSITE TWO-TONE POWER LEVELS 3.6V -28 -30 4.2V -32 -34 5 POUT, IM3, AND IM5 ARE RMS COMPOSITE TWO-TONE POWER LEVELS 3.0V 50 -24 25 MAX2601-06 POUT MAX2601-05 -20 MAX2601-04 35 POUT, IM3, IM5 (dBm) -5 27 0 40 3.6V 30 4.2V 20 4.8V 4.8V -36 10 -38 -40 -5 10 5 15 20 25 0 10 15 20 25 30 35 10 OUTPUT POWER (dBm) INPUT POWER (dBm) 15 20 25 30 35 OUTPUT POWER (dBm) ______________________________________________________________Pin Description PIN FUNCTION NAME MAX2601 MAX2602 1, 8 1, 8 C Transistor Collector 2, 3, 6, 7, Slug 2, 6, 7, Slug E Transistor Emitter — 3 BIAS 4, 5 4, 5 B Anode of the Biasing Diode that matches the thermal and process characteristics of the power transistor. Requires a high-RF-impedance, lowDC-impedance (e.g., inductor) connection to the transistor base (Pin 4). Current through the biasing diode (into Pin 3) is proportional to 1/15 the collector current in the transistor. Transistor Base _______________________________________________________________________________________ 3 MAX2601/MAX2602 __________________________________________Typical Operating Characteristics (Test Circuit of Figure 1, input/output matching networks optimized for specific measurement frequency, VCC = 3.6V, VBB = 0.750V, POUT = 30dBm, ZLOAD = ZSOURCE = 50Ω, f = 836MHz, TA = +25°C, unless otherwise noted.) MAX2601/MAX2602 3.6V, 1W RF Power Transistors for 900MHz Applications VCC VBB 5Ω 1000pF 0.1µF 100nH 24Ω 1000pF 1 4 8 1000pF RFIN 0.1µF L1 1000pF T2 10pF 2pF 5 2pF T1 12pF 2, 6, 7 BACKSIDE SLUG L1 = COILCRAFT A05T INDUCTOR, 18.5nH T1, T2 = 1", 50Ω TRANSMISSION LINE ON FR-4 Figure 1. Test Circuit _______________Detailed Description MAX2601/MAX2602 The MAX2601/MAX2602 are high-performance silicon bipolar transistors in power-enhanced, 8-pin SO packages. The base and collector connections use two pins each to reduce series inductance. The emitter connects to three (MAX2602) or four (MAX2601) pins in addition to a back-side heat slug, which solders directly to the PC board ground to reduce emitter inductance and improve thermal dissipation. The transistors are intended to be used in the common-emitter configuration for maximum power gain and power-added efficiency. Current Mirror Bias (MAX2602 only) The MAX2602 includes a high-performance silicon bipolar RF power transistor and a thermally matched biasing diode that matches the power transistor’s thermal and process characteristics. This diode is used to create a bias network that accurately controls the power transistor’s collector current as the temperature changes (Figure 2). The biasing diode is a scaled version of the power transistor’s base-emitter junction, in such a way that the current through the biasing diode is 1/15 the quiescent collector current of the RF power transistor. Supplying the biasing diode with a constant current source and connecting the diode’s anode to the RF power transistor’s base ensures that the RF power transistor’s quiescent collector current remains constant through 4 VCC VCC RBIAS RFC RFOUT COUT RFC Q1 Q2 CBIAS CIN RFIN Figure 2. Bias Diode Application temperature variations. Simply tying the biasing diode to the supply through a resistor is adequate in most situations. If large supply variations are anticipated, connect the biasing diode to a reference voltage through a resistor, or use a stable current source. Connect the biasing diode to the base of the RF power transistor through a large RF impedance, such as an RF choke (inductor), and decouple to ground through a surfacemount chip capacitor larger than 1000pF. _______________________________________________________________________________________ 3.6V, 1W RF Power Transistors for 900MHz Applications Optimum Port Impedance The source and load impedances presented to the MAX2601/MAX2602 have a direct impact upon its gain, output power, and linearity. Proper source- and loadterminating impedances (ZS and ZL) presented to the power transistor base and collector will ensure optimum performance. For a power transistor, simply applying the conjugate of the transistor’s input and output impedances calculated from small-signal S-parameters will yield less than optimum device performance. For maximum efficiency at VBB = 0.75V and VCC = 3.6V, the optimum power-transistor source and load impedances (as defined in Figure 3) are: At 836MHz: ZS = 5.5 + j2.0 ZL = 6.5 + j1.5 At 433MHz: ZS = 9.5 - j2.5 ZL = 8.5 - j1.5 ZS and ZL reflect the impedances that should be presented to the transistor’s base and collector. The package parasitics are dominated by inductance (as shown in Figure 3), and need to be accounted for when calculating ZS and ZL. The internal bond and package inductances shown in Figure 3 should be included as part of the endapplication matching network, depending upon exact layout topology. Slug Layout Techniques The most important connection to make to the MAX2601/MAX2602 is the back side. It should connect directly to the PC board ground plane if it is on the top side, or through numerous plated through-holes if the ground plane is buried. For maximum gain, this connection should have very little self-inductance. Since it is also the thermal path for heat dissipation, it must have low thermal impedance, and the ground plane should be large. 4 3 2 1 MAX2601 MAX2602 2.8nH 2.8nH 2.8nH ZS 5 2.8nH ZL 6 7 8 Figure 3. Optimum Port Impedance _______________________________________________________________________________________ 5 MAX2601/MAX2602 __________Applications Information MAX2601/MAX2602 3.6V, 1W RF Power Transistors for 900MHz Applications ________________________________________________________Package Information DIM D 0°-8° A 0.101mm 0.004in. e B A1 C L 8-Pin PSOPII E 6 H A A1 B C E e H L INCHES MAX MIN 0.069 0.053 0.010 0.004 0.019 0.014 0.010 0.007 0.157 0.150 0.050 0.244 0.228 0.050 0.016 DIM PINS D 8 MILLIMETERS MIN MAX 1.35 1.75 0.10 0.25 0.35 0.49 0.19 0.25 3.80 4.00 1.27 5.80 6.20 0.40 1.27 INCHES MILLIMETERS MIN MAX MIN MAX 0.189 0.197 4.80 5.00 _______________________________________________________________________________________ 21-0041A