lt5503 Linear Technology Corporation, lt5503 Datasheet
lt5503
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lt5503 Summary of contents
Page 1
... In a superheterodyne system, the mixer can be used to generate the high-frequency RF input for the modulator by mixing the system’s 1st and 2nd local oscillators. The LT5503 modulator output delivers –3dBm at 2.5GHz. The VGA allows output power reduction in three steps up to 13dB with digital control. The baseband inputs are internally biased for maximum input voltage swing at low supply voltage ...
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... PACKAGE 20-LEAD PLASTIC TSSOP PIN 21 = GND (BACKSIDE 150 C, JMAX Consult LTC Marketing for parts specified with wider operating temperature ranges ORDER PART NUMBER – LT5503EFE 18 GC2 17 MODOUT 16 V VGA LO2 CC 14 LO2 13 MODEN 12 MIXEN – ...
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... 100kHz 120kHz 100kHz 120kHz I Q 20MHz Offset GC2 = Low, GC1 = High GC2 = High, GC1 = Low GC2 = High, GC1 = High V MODEN = High MODEN = Low LT5503 ] and [Q – MIN TYP MAX UNITS 1.2 to 2.7 GHz 1.3:1 –20 to -10 dBm 120 MHz 1 V P-P 1.4 VDC ...
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... LT5503 ELECTRICAL CHARACTERISTICS V = 3VDC, 2.4GHz matching, MIXEN = High, DMODE = Low (LO2 2 mode), T CC2 2075MHz at –12dBm. MIXRFOUT measured at 2450MHz, unless otherwise noted. (Test circuit shown in Figure 2.) (Note 3) PARAMETER Mixer 2nd LO Input (LO2IN) Frequency Range Input VSWR Input Power Mixer 1st LO Input (LO1IN) ...
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... G05 Typical SSB Spectrum 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 2449.6 2449.8 2450.0 2450.2 2450.4 2450.6 FREQUENCY (MHz) 5503 G07 LT5503 ) and B MODEN Current vs Enable Voltage 220 MODEN = V CC1 200 180 160 140 ...
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... LT5503 W U TYPICAL PERFOR A CE CHARACTERISTICS 2.4GHz matching, MODEN = high, GC1 = GC2 = low (max gain), MODRFIN = 2.45GHz, (I–I differential, Q leads unless otherwise noted. (Test circuit shown in Figure 2.) SSB Output Power vs Input Power V = 1.8V CC1 – –4 – – –8 ...
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... Carrier Feedthrough vs Frequency 2.4GHz Matching –30 GC2, GC1 = 00 01 – –50 –60 2250 2350 2450 2550 MODRFIN FREQUENCY (MHz) 5503 G24 LT5503 (I/Q Modulator) differential, Q leads P-P SSB Image vs Frequency 1.2GHz Matching –30 GC2, GC1 = 00 01 – –50 –60 1400 1000 ...
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... LT5503 W U TYPICAL PERFOR A CE CHARACTERISTICS 2.4GHz matching, MIXEN = high, DMODE = low (LO2 2 mode), LO2IN = 750MHz at –18dBm, LO1IN = 2075MHz. MIXRFOUT measured at 2450MHz, unless otherwise noted. (Test circuit shown in Figure 2.) Mixer Supply Current vs Supply Voltage (LO2 2 Mode ...
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... C A 240 210 T = – 180 150 120 1.8 4.6 2.5 3.2 3.9 MIXEN VOLTAGE (V) LT5503 (Mixer) LO1IN and MIXRFOUT Return Loss 1.9GHz Matching –3 0 –5 –6 –10 –9 –15 MIXRFOUT –12 –20 LO1IN –15 –25 –18 –30 1100 1700 1900 2150 ...
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... LT5503 CTIO S – BQ (Pin 1): Negative Baseband Input Pin of the Modulator Q-Channel. This pin is internally biased to 1.4V, but can also be overdriven with an external DC voltage greater than 1.4V, but less than V – 0.4V (Pin 2): Positive Baseband Input Pin of Modulator Q- Channel. This pin is internally biased to 1.4V, but can also be overdriven with an external DC voltage greater than 1 ...
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... V-I V-I 5 VGA 6 CONTROL LOCIC BUFFER 4 MODULATOR BIAS CIRCUITS MIXER BIAS CIRCUITS 8 LO1 BUFFER 2 LIM – GND MX MX DMODE (BACKSIDE) LT5503 16 V VGA CC MODOUT 17 18 GC2 3 GC1 13 MODEN 12 MIXEN 15 V LO2 CC LIM LO2 14 5503 BD 11 ...
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... CC1 LO1IN V CC2 C2, C3, C7 C10 C23 C11 L4 L5,L6 T1 Figure 2. Test Schematic for 1.2GHz, 1.9GHz and 2.4GHz Applications 12 21 (BACKSIDE) C17 1 F LT5503 GND 1 20 – – C15 GC1 GC1 GC2 GC2 C3 L3 ...
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... U U APPLICATIO S I FOR ATIO The LT5503 consists of a direct quadrature modulator and a mixer. The mixer operates over the range of 1.7GHz to 2.7GHz, and the modulator operates with an output range of 1.2GHz to 2.7GHz. The LT5503 is designed specifically for high accuracy digital modulation with supply voltages as low as 1 ...
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... W U Figure 5 shows a simplified circuit schematic for interfac- ing the LT5503’s baseband inputs to the outputs of a D/A converter. OIP and OIN are the positive and negative baseband outputs, respectively, of the converter’s I-channel. Similarly, OQP and OQN are the positive and negative baseband outputs, respectively, of the converter’ ...
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... Figure 6 where inductors LB differential outputs, and resistor R unused output. – L5, 5503 F06 Figure 6. 50 Mixer Output Matching Without a Balun LT5503 + – / – and LB supply bias current to the mixer’s terminates the TERM 1.9GHz 2.4GHz 5.6nH 2 ...
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... LT5503 U U APPLICATIO S I FOR ATIO EVALUATION BOARD Figure 7 shows the circuit schematic of the evaluation board. The MODRFIN, MODRFOUT and MIXRFOUT ports are matched 2.45GHz. The LO1IN port is matched 2.1GHz and the LO2IN port is internally matched. A 390 resistor is used to reduce the quality factor (Q) of the modulator output and deliver an output power of – ...
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... GND *L5 *L6 2.7k 20k 2.7k *C5 * CC2 C21 C13 0.01 F 8.2pF *C9 MIXER T1 OUT 5503 F07 LT5503 C29 C28 4.7 F 0. U3-1 R15 R16 LT1807 510 510 56 – R18 4 6 510 1% C16 R28 1 F C36, 39pF 49.9 C38, 1pF ...
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... LT5503 U U APPLICATIO S I FOR ATIO GND MODRFIN LO1IN QIN IIN LT1807 LT5503 IC GND V CC2 MIXRFOUT Figure 8. LT5503 Evaluation Board Layout V CC4 V CC1 LT1807 V4 MODRFOUT LO2IN CC3 6 5503 F08 ...
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... LT5503 IC GND V CC2 + MIXRFOUT – EXTERNAL 3dB ATTENUATOR PAD, OR 2.45GHz BPF Figure 9. Test Set-Up for Upconverting Mixer and I/Q Modulator Transmit Chain Measurements. LT5503 + – POWER SUPPLY 4 + – POWER SUPPLY 1 V CC4 SPECTRUM LT1807 ANALYZER MODRFOUT SIGNAL GENERATOR 1 1 LO2IN ...
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... LT5503 PACKAGE DESCRIPTIO 6.60 0.10 4.50 0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.45 – 0.75 0.09 – 0.20 (.018 – .030) (.0036 – .0079) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE RELATED PARTS PART NUMBER DESCRIPTION LT5502 400MHz Quadrature IF Demodulator with RSSI ...