TSH690IDT

TSH690 40MHz to 1GHz AMPLIFIER ■ ■ ■ ■ ■ ■ ■ Supply voltage: 1.5V to 5V >20 mW adjustable output power 28 dB gain at 450 MHz 21 dB gain at 900 MHz 50 Ω matched input and output Bias pin to adjust the amplification class Power down PACKAGE DESCRIPTION The TSH690 is a wide band RF amplifier, designed in advanced bipolar process. At 450 MHz, it features 28dB gain and +13.5dBm (20 mW) output power at 3V. At 900 MHz, it features 23 dB gain and +15.5 dBm (35 mW) output power at 3V. The pin 8 allows a bias current adjust, setting the RF output level and the amplifier behaviour. It allows using the TSH690 from the linear A-class trough the AB-class to power-down mode. The TSH690 is suited to drive power amplifiers in cellular phones (GSM, TDMA) for which the ’turn-on time’ is controlled by a voltage ramp. The more than 20 mW output power makes the TSH690 dedicated as output stage for 433MHz and 868 MHz ISM transmitters. D SO8 (Plastic Micropackage) PIN CONNECTIONS (top view) APPLICATIONS ■ ■ ■ ■ ■ ■ 433 MHz and 868 MHz ISM transmitters Telemetering systems Remote controls Cordless Telephones Driver for cellular phones Wide band applications ORDER CODE Package Part Number Temperature Range D TSH690ID -40, +85°C • D = Small Outline Package (SO) - also available in Tape & Reel (DT) March 2001 1/14 TSH690 SCHEMATIC DIAGRAM ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit 5.5 +10 +21 -40 to +85 V dBm dBm °C -65 to +150 °C Value Unit 1.5 to 5 V VCC1, VCC2, Vbias Supply Voltage & Bias Voltage RF in RF Input Power RF out RF Output Power Toper Operating Free Air Temperature Range Tstg Storage Temperature Range OPERATING CONDITIONS Symbol VCC1, VCC2 Parameter Supply Voltages Vbias Bias Voltage RFsr RF Signal Range ESD SENSITIVE DEVICE Handling Precautions Required 2/14 0 to 5 V 40 to 1000 MHz TSH690 ELECTRICAL DC CHARACTERISTICS Tamb = 25°C, VCC connected to V bias, ZL = 50Ω (unless otherwise specified) Parameter Min. Typ. Max. Unit Supply Current Vcc = 2V 29 Vcc = 2.7V 46 Vcc = 3V 33 mA 53 Vcc = 4V 79 Vcc = 5V Rth-(j-a): Junction Ambient Thermal Resistance for SO-8 Package 105 TSH690 DISSIPATION CONSIDERATIONS In order to respect the dissipation limitation of the package, you should consider the following equation: 140 180 °C/W determining ICC, thanks to the direct reading curve: Figure 2 : Maximum Tamb vs V CC 160 Tj - Tamb = Pd • Rth(j-a) VBIAS=VCC RTHmax=180°C/W 140 120 with: Tj (°C) = max. junction temperature (150°C) TAMB(°C) 100 Rth(j-a) = junction ambient thermal resistance 80 SAFE AREA 60 40 Tamb (°C) = ambient temperature 20 Pd (W) = maximum dissipated power 0 0 The respect of this condition forms a safe area on the following figure: Figure 1 : Dissipation capability vs T ambient 900 VBIAS = VCC RTH = 180°C/W 800 PdMAX(mW) 700 3 4 5 6 In applications using a duty cycle, the average dissipation is less than in continuous mode. The following figure gives the relation beetween the dissipated power and the duty cycle. Figure 3 : Dissipation vs Duty cycle 900 500 800 SAFE AREA Pd = VCC x ICC x Duty Cycle VCC = 5V 700 300 Pd(mW) 600 200 100 0 -40 -30 -20 -10 0 2 VCC(V) 600 400 1 10 20 30 40 50 60 70 80 90 TAMB(°C) VCC = 4V 500 400 VCC = 3V 300 200 VCC = 2V 100 0 0 If VBIAS is DC connected to VCC, the operating temperature can be directly determined without 10 20 30 40 50 60 70 80 90 100 Duty Cycle(%) 3/14 TSH690 ELECTRICAL CHARACTERISTICS AT 450 MHz Tamb = 25°C, VCC & Vbias = +2.7V, Z L = 50Ω, f = 450 MHz (unless otherwise specified) Parameter1) Power gain S21 (Pin = -20dBm) Output Power 1dB Compression 3rd Order Intercept Point (f = 430MHz) Reverse Isolation S12 (f = 400MHz) Input Return Loss S11 Noise Figure Min. Typ. Max. Unit 20 8 16 23 12 22 -46 -15 4.5 30 dB dBm dBm dB dB dB Max. Unit -10 1. All min. and max. parameters of this table are garanteed by correlation with 900 MHz tests. ELECTRICAL CHARACTERISTICS AT 900 MHz Tamb = 25°C, VCC & Vbias = +3V, ZL = 50Ω, f = 900 MHz (unless otherwise specified) Parameter1) Power gain S21 (Pin = -20dBm) Output Power at 1dB compression point Output power, Pin = -7 dBm 3rd Order Intercept Point Reverse Isolation S12 Input Return Loss S11 Output Return Loss S22 Noise figure 1. All min. and max. parameters of this table are garanteed by test. 4/14 Min. Typ. 19 +12 +10 21 +14.3 +11.7 +25 -35 -14 -4.5 5.4 dB dBm dBm dBm dB dB dB dB TSH690 SCATTERING PARAMETERS MEASUREMENT (Reference waves planes at package leads) TEST CONDITIONS VCC1, VCC2, Vbias = +2V, Pin = -40dBm, Tamb = 25°C Freq S11 S21 S12 S22 MHz Mag Ang Mag Ang Mag Ang Mag Ang 40 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 0.642 0.615 0.537 0.490 0.464 0.428 0.413 0.373 0.334 0.312 0.290 0.302 0.324 0.335 0.349 0.368 0.366 0.373 0.374 0.381 0.377 -22.0 -25.7 -41.3 -55.6 -68.0 -79.0 -92.1 -101.5 -106.7 -111.5 -112.5 -114.5 -118.2 -122.9 -129.6 -135.0 -142.1 -147.9 -154.1 -159.0 -165.8 6.319 6.406 7.643 9.353 11.502 13.856 16.229 18.019 19.110 19.159 18.154 16.778 15.075 13.482 11.992 10.750 9.453 8.598 7.783 7.117 6.500 5.0 7.1 7.7 3.1 -5.7 -18.0 -33.4 -51.2 -70.1 -90.3 -108.0 -124.8 -140.5 -153.6 -165.5 -177.2 173.4 165.0 155.8 146.7 138.9 0.003 0.008 0.002 0.004 0.007 0.003 0.005 0.008 0.008 0.008 0.008 0.010 0.015 0.011 0.011 0.019 0.011 0.015 0.013 0.017 0.013 -126.5 170.7 70.1 -141.9 -117.3 162.3 142.1 101.4 115.2 169.9 111.5 92.1 93.6 109.6 101.7 82.4 79.5 60.2 89.7 111.3 82.2 0.715 0.631 0.369 0.253 0.202 0.203 0.209 0.263 0.326 0.382 0.395 0.425 0.424 0.427 0.425 0.414 0.413 0.432 0.438 0.447 0.462 -54.7 -64.7 -91.3 -100.9 -100.9 -92.7 -87.6 -89.4 -99.7 -112.1 -122.9 -130.0 -139.6 -150.8 -159.0 -169.5 -177.8 176.2 166.4 160.8 155.1 5/14 TSH690 TEST CONDITIONS VCC1, VCC2, Vbias = +3V, Pin = -40dBm, Tamb = 25°C Freq S11 S21 S12 S22 MHz Mag Ang Mag Ang Mag Ang Mag Ang 40 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 0.616 0.595 0.513 0.470 0.436 0.402 0.382 0.343 0.302 0.279 0.271 0.280 0.306 0.315 0.330 0.333 0.343 0.346 0.354 0.347 0.355 -23.3 -27.0 -43.4 -57.7 -71.1 -82.2 -95.0 -103.3 -109.7 -114.8 -114.0 -116.1 -119.8 -125.5 -131.1 -136.2 -142.5 -148.0 -155.1 -159.6 -166.2 9.237 9.402 11.263 13.566 16.434 19.416 22.265 24.337 25.564 25.594 24.292 22.527 20.511 18.282 16.311 14.604 12.860 11.668 10.579 9.652 8.775 6.2 7.9 6.5 0.9 -8.6 -21.3 -36.6 -53.7 -71.8 -91.2 -108.3 -124.7 -140.1 -153.2 -165.1 -177.1 173.6 165.1 156.0 147.0 139.2 0.002 0.005 0.006 0.006 0.007 0.007 0.005 0.008 0.010 0.008 0.011 0.013 0.005 0.006 0.007 0.012 0.017 0.014 0.018 0.013 0.018 -135.8 -169.5 -153.8 94.5 155.8 154.1 7.2 40.6 125.9 167.1 120.2 101.0 89.9 107.2 78.9 84.5 76.0 90.8 75.6 66.6 75.3 0.733 0.651 0.381 0.227 0.156 0.134 0.135 0.193 0.269 0.316 0.356 0.396 0.404 0.400 0.406 0.398 0.399 0.411 0.413 0.439 0.459 -56.9 -67.7 -101.7 -119.1 -117.5 -100.3 -75.7 -78.0 -86.1 -100.6 -111.0 -119.3 -131.3 -142.6 -151.6 -160.4 -170.5 -178.8 170.9 165.2 157.3 TEST CONDITIONS VCC1, VCC2, Vbias = +4V, Pin = -40dBm, Tamb = 25°C Freq MHz 40 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 6/14 S11 Mag 0.614 0.590 0.508 0.465 0.429 0.396 0.371 0.335 0.295 0.275 0.265 0.282 0.296 0.314 0.321 0.334 0.339 0.348 0.340 0.352 0.341 S21 Ang -23.1 -27.4 -44.6 -59.9 -72.0 -83.4 -94.7 -103.8 -109.9 -114.8 -114.8 -117.0 -120.3 -124.7 -131.5 -135.8 -143.8 -149.4 -157.5 -161.0 -166.8 Mag 11.023 11.248 13.262 15.736 18.727 21.837 24.804 26.854 28.077 28.113 26.710 24.831 22.620 20.235 18.081 16.178 14.235 12.941 11.693 10.670 9.683 S12 Ang 6.9 7.9 4.5 -2.0 -11.5 -24.2 -39.3 -56.0 -73.6 -92.5 -109.4 -125.5 -140.8 -154.1 -166.2 -178.0 172.5 164.1 154.9 145.7 137.6 Mag 0.002 0.003 0.004 0.006 0.003 0.002 0.009 0.006 0.003 0.010 0.007 0.007 0.007 0.005 0.010 0.012 0.010 0.014 0.014 0.006 0.016 S22 Ang 107.6 -111.3 -47.0 -62.5 97.7 -135.5 154.7 135.2 139.7 97.0 111.8 93.8 110.0 85.1 93.2 106.1 74.1 57.9 80.2 87.4 50.0 Mag 0.726 0.646 0.366 0.206 0.130 0.108 0.136 0.191 0.262 0.321 0.335 0.389 0.393 0.402 0.388 0.390 0.377 0.392 0.402 0.409 0.433 Ang -54.4 -65.1 -97.6 -110.4 -104.3 -78.6 -56.7 -64.3 -75.2 -85.8 -98.2 -108.5 -121.0 -131.7 -143.9 -153.8 -162.4 -170.4 179.5 171.4 163.3 TSH690 Figure 4 : Demonstration board schematic TSH690 DESCRIPTION DC BLOCKING The TSH690 is a 2 transistor stages amplifier running within the 40MHz-1GHz frequency band featuring a gain of 28dB at 433MHz. The TSH690 is 50Ω input/output internally matched from 300MHz to 1000MHz. The open collector output requires an inductive load for the impedance matching and also to reach an output power of +13,5dBm at 3V and +18dBm at 4V. A bias control pin allows tuning of current consumption and amplification mode. Because input/output are respectively internal/external biased, DC blocks (C1, C2) are recommended on both RF ports to guarantee a DC isolation from the next cells. Above 500MHz, 100pF is suggested whereas below, 1nF is better and far below (less than 100MHz), 10nF is prefered. As the matter of fact, when the bias pin is tied to the supply voltage, amplification is linear (Class A) while a lower voltage leads to a Class A-B amplification featuring a better efficiency. If the control voltage is grounded, the TSH690 is set in Power-down mode without current consumption. MATCHING THE OUTPUT WITH L2 Within the 300-1000MHz band, although the circuit is matched, the output return loss (S22) can be improved by adapting the value of the inductor L2. This inductor is connected between the RF output and VCC2. L2 = 56 nH gives an output return loss of -19 dB at 450 MHz. L2 = 10 nH gives an output return loss of - 8 dB at 900 MHz. In a 433 or 450 MHz transmitter application, L1 and L2 can be optimized to reduce the second harmonic by choosing L1 = 33nH and L2 = 15nH. Below 300MHz, using the S-parameters matrix, specific input/output matching networks can be calculated to maximize electrical performances. BIASING The amplifier can operate in the range of 1.5V to 5V and offers a bias current adjust function (Vbias pin) which enables the trimming of the RF output power (AB class Amplifier) by tuning a series variable resistor (Rbias). When Vbias is wired to the Vcc rail, the current consumption is maximized getting the best linearity (A class Amplifier) whereas biasing to Ground, the IC is set in power down mode. For higher supply voltage than 4V to reach high output power, the serial resistor (R1) is strongly recommended to increase the efficiency of the amplifier and therefore reduce the thermal dissipation of the circuit. DECOUPLING As with any RF devices, the supply voltage decoupling must be done carefully using a 1nF bypass capacitor (C3, C5) placed as close as possible to the device pins and could be also improved by adding a 150nH RF choke inductance (L1). Concerning the Vbias pin, a 10nF decoupling capacitor (C4) is recommended while placing on board is not critical. Note that Surface Mounted Devices (SMD) components are prefered for RF applications due to the right behaviour in high frequencies while low inductor values (few 10nH) can be printed on board. 7/14 TSH690 DETERMINING VBIAS AND R1 AT 450 MHz Using the 450 MHz curves, you can easily determine VBIAS voltage and R1 to obtain the desired power gain S21. For a given gain S21 and a given supply voltage VCC, you can determine the corresponding VBIAS.using the curve ’Gain vs VBIAS’ in the ’450 MHz operation’ section. It’s generally more convenient to supply the Vbias from VCC than generate a separate voltage. You just need to add the R1 resistor beetween the VBIAS pin and VCC. Using the curve ’Supply current vs Bias voltage’ you can determine the current IBIAS corresponding to a VBIAS . R1 can calculated by: R1 = (VCC - VBIAS ) / IBIAS. One the same curve, you will find the total current supply Icc versus the biasing conditions. Figure 5 : Demo board silk screen (not to scale) 8/14 Figure 6 : Demo board top side (not to scale ) TSH690 450 MHz operation (L2 = 56 nH) GAIN vs FREQUENCY OUTPUT RETURN LOSS 0 -5 3V S22 (dB) 2V -10 4V -15 -20 Vcc=Vbias @ Ta=+25°C L2=56nH (450MHz operation) -25 100 INPUT RETURN LOSS 200 300 400 500 600 Freq (MHz) 700 800 900 1000 GAIN vs VBIAS VOLTAGE 0 30 25 -5 V CC = 4V 20 S11 (dB) 3V S21(dB) 2V -10 V CC = 2V 10 T AMB = 25°C Freq = 450MHz 0 4V -25 100 15 5 -15 -20 V CC = 3V -5 Vcc=Vbias @ Ta=+25°C L2=56nH (450MHz operation) 200 300 400 500 600 Freq (MHz) -10 0.5 700 800 900 1000 1.0 1.5 2.0 2.5 3.0 3.5 4.0 VBIAS (V) 9/14 TSH690 900 MHz operation (L2 = 10 nH) OUTPUT RETURN LOSS GAIN vs FREQUENCY 30 -40°C +25°C V +85°C Gain (dB) 25 20 15 L2 =10nH (900MHz Operation) Vcc=Vbias=3V 10 100 200 300 400 500 600 Freq (MHz) 700 800 900 1000 OUTPUT POWER vs INPUT POWER INPUT RETURN LOSS 20 0 -5 2V S11 (dB) -10 Pout (dBm) 15 3V +85°C 10 +25°C -15 4V 5 -20 -25 100 Vcc=Vbias @ Ta=+25°C L2 =10nH (900MHz operation) 200 300 400 Vcc=Vbias=3V L2 =10nH (900MHz operation) 500 600 Freq (MHz) 700 800 900 1000 OUTPUT POWER vs VBIAS 20 P1dB (dBm) 15 Vcc = 4V Vcc = 3V 10 Vcc = 2V 5 Ta=25°C L2 =10nH (900MHz operation) 0 1,5 2 2,5 3 Vbias (V) 10/14 -40°C 3,5 4 0 -20 -15 -10 Pin (dBm) -5 0 TSH690 Other curves SUPPLY CURRENT vs BIAS VOLTAGE 60 6 Icc total 40 I bias (mA) 4 Icc total (mA) REVERSE ISOLATION vs FREQUENCY I bias 20 2 Vcc=3V, Ta=+25°C Pin = -40dBm 0 0 0 0,5 1 1,5 Vbias (V) 2 2,5 3 11/14 TSH690 ASK TRANSMITTER USING THE TSH690 Application purpose The purpose is to use the TSH690 as a ASK transmitter for remote control applications taking benefits of the 2 stages architecture, the bias control pin and output power capability. The first transistor stage is devoted to the oscillator by the meaning of a Surface Acoustic Wave (SAW) resonator while the second stage realizes the power amplification to drive antennas including the impedance matching. Modulation is insured by applying the modulating signal onto the bias pin of TSH690 to get an amplitude modulation. Figure 7 : Saw transmitter schematic By tuning R1 and C1, stability of the circuit can be guaranted disregarding the load impedance of the output stage. Output Stage The output matching is defined for a 50Ω load impedance by adding a 100nH self-inductor L2 as load to the open collector of the output stage while capacitor C3 is just placed as a DC block with the antenna. In such described conditions, output power on fundamental reaches more than +13dBm under 3V with an average current consumption of 50mA featuring 2nd & 3rd harmonics levels respectively of -18dBc et -27dBc. Modulation As a result of applying a modulating signal to the bias pin (pin 8), the TSH690 features an amplitude modulation up to the On-Off-Keying when the modulating signal is digital. A series resistor R2 can be added on pin 8 to change biasing conditions but also oscillating conditions and finally the available output power. In most of applications, this resistor can be omitted. Oscillator Considerations The oscillator frequency is given by the SAW resonator which is connected between pins 5 & 7 of the TSH690 to ensure a well-known Colpitts architecture with 2 capacitors C1 and C2. Capacitor C2 is a small value one and, depending on PCB, could be directly obtained from parasitics of microstrip lines. Center frequency is tuned with the trimmer capacitor C1. Note that the pin 7 is internally connected to an integrated self inductor L1 which is wired to the collector of the first stage transistor. A resistor R1 is placed to avoid resonance between L1 and C1 but also to adjust the current consumption of the oscillator. Moreover, start-up conditions and output harmonics levels are related to the R1 value, so that its recommended to use a potentiometer for R1. 12/14 In the case of digital modulation control, when a ‘0’ logic level is applied on pin 8, the circuit in set in Standby mode during which the oscillator is stopped whereas during a ‘1’ logic level, the circuit radiates RF wave due to oscillator running mode.The maximum data rate of modulating signal is given by the oscillator turn-on time which is typically of 200µs to reach the nominal operating frequency and amplitude. Note that the turn-off time is negligeable. Thus, it is recommended to use a data rate of 2400b/s to keep a duty cycle of 25% (T_ON~200µs, T_OFF~(400+200)µs). For a higher data rate (maximum of 4800b/s), duty cycle on transmission side decreases drastically so that it is recommended to use a monostable on reception side to recover a correct 50% duty cycle. In order to decrease the spectrum shape of transmission, a simple low-pass filter can be added in front of pin 8 to attenuate high level harmonics of the modulating signal. TSH690 Figure 8 : PCB component side (not to scale) Figure 9 : PCB solder side (not to scale) Routing Requirements Figure 10 : Silk screen (not to scale) Supply voltages : as well as any RF design boards, decoupling of supply voltages requires carefully routing. So, the output stage features a 10µF tank capacitor to smooth current peaks and 2 decoupling capacitors of 1nF and 100pF avoiding a RF feedback to the supply. The oscillator biasing (pin 7) requires a RF choke self inductance of 56nH in series with R1 and also a grounded decoupling capacitor of 1nF. Ground : The ground routing has to be done in the manner of decreasing resistive and inductive parasitics effects to guarantee the best equipotential of the electrical ground node. By using microstrip lines, bottom and top ground planes must be connected via through holes in respect with a distance shorter than 10 times the running wavelength. In practice, with a standard epoxy substrate (Er~4,5), to run at about 450MHz, distance between 2 vias must not exceed ~3cm. By using a standard 2.54mm PCB grid, design takes profit to avoid harmonics radiation. Improvements In comparison with the first diagram proposal, 2nd & 3rd harmonics levels can be reduced respectively as low as -27dBc and -34dBc by replacing L2 with a parallel tank circuit (LC) of 10nH, 13pF. In such a condition, fundamental output level is slightly degraded of less than 0.5dB keeping a good 50Ω impedance matching. 13/14 TSH690 PACKAGE MECHANICAL DATA 8 PINS - PLASTIC MICROPACKAGE (SO) Millimeters Inches Dim. Min. A a1 a2 a3 b b1 C c1 D E e e3 F L M S Typ. Max. 0.65 0.35 0.19 0.25 1.75 0.25 1.65 0.85 0.48 0.25 0.5 4.8 5.8 5.0 6.2 0.1 Min. Typ. Max. 0.026 0.014 0.007 0.010 0.069 0.010 0.065 0.033 0.019 0.010 0.020 0.189 0.228 0.197 0.244 0.004 45° (typ.) 1.27 3.81 3.8 0.4 0.050 0.150 4.0 1.27 0.6 0.150 0.016 0.157 0.050 0.024 8° (max.) Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. © The ST logo is a registered trademark of STMicroelectronics © 2001 STMicroelectronics - Printed in Italy - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom © http://www.st.com 14/14