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dc1774acf

DEMO MANUAL DC1774A-C

 QUICK START PROCEDURE

Demo circuit 1774A-C can be set up to evaluate the per-
formance of the LTC6431-15. Refer to Figures 7 and 8, for 
proper equipment connections and follow the procedure 
below:

Single-Tone Measurement:

Connect all test equipment as suggested in Figure 7

1. The power labels of +5V and GND directly correspond 

to the power supply. Typical current consumption of 
the LTC6431-15 is about 90mA.

2.  Apply an input signal to J7. A low-distortion, low noise 

signal source with an external high order lowpass filter 
will yield the best performance. (i.e. the input signal is 
–10dBm. The Input is impedance matched to 50Ω).

3. Observe the output via J10. (The measured power at 

the analyzer should be about +5dBm. The output is 
impedance matched to 50Ω), suitable for the input of 
a network or spectrum analyzer.

Two-Tone Measurement:

Connect all test equipment as suggested in Figure 8.

1. The power labels of +5V and GND directly correspond 

to the power supply. Typical current consumption of 
the LTC6431-15 is about 90mA.

2.  Apply two independent signals f1 and f2 from SG1 and 

SG2 at 240MHz and 241MHz respectively.

3.  Monitor the output tone level on the spectrum analyzer. 

Adjust signal generator levels such that output power 
me2dBm/tone at the amplifier output J10, after 
correcting for external cable losses and attenuators.

4. Change the spectrum analyzer’s center frequency and 

observe the two IM3 tones at 1MHz below and above 
the input frequencies. (i.e. the frequencies of IM3_LOW 
and IM3_HIGH are 239MHz and 242MHz, respectively. 
The measurement levels should be approximately 
–90dBc; +47dBm is a typical performance of OIP3 
at 240MHz). For this setup, the Rohde and Schwarz 
FSEM30 spectrum analyzer was used. This SA has a 
t20dBm third-order intercept point (TOI). So, 
the SA input attenuation is set to 20dB with an external 
20dB attenuation pad, resulting in an attenuation total 
of 40dB. The system as described can measure OIP3 
up to +50dBm.

Figure 1. LTC6431-15 Device Block Diagram

OUT
(PIN 18)

T-DIODE
(PIN 16)

GND
(PINS 8, 17, 23 AND EXPOSED PAD 25)

V

CC

(PINS 9, 22)

IN

(PIN 24)

dc1774ac F01

BIAS AND

TEMPERATURE

COMPENSATION

Содержание DC1774A-C

Страница 1: ...e at TA 25 C VCC 5V SYMBOL PARAMETER CONDITIONS VALUE UNIT Power Supply VCC Operating Supply Range All VCC Pins Plus OUT 4 75V to 5 25V ICC Current Consumption Total Current 90mA FREQUENCY MHz POWER GAIN S21 dB OUTPUT THIRD ORDER INTERCEPT POINT 1 OIP3 dBm OUTPUT THIRD ORDER INTERMODULATION 1 OIM3 dBc SECOND HARMONIC DISTORTION 2 HD2 dBc THIRD HARMONIC DISTORTION 2 HD3 dBc OUTPUT 1dB COMPRESSION P...

Страница 2: ...to the power supply Typical current consumption of the LTC6431 15 is about 90mA 2 Apply two independent signals f1 and f2 from SG1 and SG2 at 240MHz and 241MHz respectively 3 Monitortheoutputtonelevelonthespectrumanalyzer Adjust signal generator levels such that output power measures 2dBm toneattheamplifieroutputJ10 after correcting for external cable losses and attenuators 4 Change the spectrum a...

Страница 3: ...V J7 IN R2 348 C8 62pF C22 0 1uF E3 U1 2 14 1 24 4 6 8 10 21 19 17 22 20 18 16 5 9 11 15 12 13 3 23 7 25 DNC GND DNC IN DNC DNC GND N C DNC DNC GND VCC DNC OUT T_DIODE DNC VCC N C DNC N C DNC DNC GND DNC GND C1 1000pF J10 OUT C7 1000pF C20 1000pF C3 1000pF FREQUENCY MHz NOMINAL WORKING FREQUENCY RANGE 0 S21 dB 18 14 10 6 16 12 8 4 S11 S12 S22 dB 0 8 16 24 4 12 20 28 6 14 22 2 10 18 26 1600 800 dc1...

Страница 4: ... limited by on chip matching elements TheSchematicDiagramsectionshowsthePCB sschematic of the amplifier family LTC643X YY Hence the board can be modified for multiple demo board versions For example both DC1774A A and DC1774A B demo boards have a differential amplifier at U1 therefore the board Anoptionalparallel62pF C8 and348Ω R2 inputnetwork has been added to insure low frequency stability Table...

Страница 5: ...n of the intermodulation products amplitude in dBc relative to the main tone power i e adjust fre quency span and resolution bandwidth to display the noise floor The wider span frequency will take a longer time to sweep e Insert a small attenuator pad 3dB or 6dB at the signal combinerinputs intothesetupandobserveifthesetup limitstheintermodulationproductslevel i e foragood IP3 test setup with suff...

Страница 6: ...4A ROHDE AND SCHWARZ FSEM30 COAXIAL CABLE LOWPASS FILTER OPTIONAL 3dB ATTENUATION PAD OPTIONAL ASSY U1 FREQ A LTC6430IUF 15 100MHz TO 300MHz B LTC6430IUF 15 400MHz TO 1000MHz C LTC6431IUF 15 100MHz TO 1200MHz DC POWER SUPPLY GND V Figure 6 IMD Buried in the Noise Floor Figure 5 Not Enough Input Attenuation 2dBm 80 dBm Noise Floor at 101dBm 2dBm Noise Floor at 81dBm ...

Страница 7: ...HDE AND SCHWARZ FSEM30 COAXIAL CABLE 20dB ATTENUATION PAD LOWPASS FILTER 6dB ATTENUATION PAD OPTIONAL COMBINER MINI CIRCUIT ADP 2 9 3dB ATTENUATION PAD SIGNAL GENERATOR 2 HP8644A AMPLIFIER MINI CIRCUIT ZHL 2 OR EQUIVALENT 6dB ATTENUATION PAD OPTIONAL LOWPASS FILTER ASSY U1 FREQ A LTC6430IUF 15 100MHz TO 300MHz B LTC6430IUF 15 400MHz TO 1000MHz C LTC6431IUF 15 100MHz TO 1200MHz DC POWER SUPPLY GND ...

Страница 8: ... 0603LS 561XJLB 15 0 L11 L22 INDUCTOR CHIP 1008LS 2520 OPT 16 1 R2 RES CHIP 348Ω 1 0402 YAGEO RC0402FR 07348RL 17 0 R5 R6 RES CHIP 348Ω 1 0402 OPT 18 0 R19 RES CHIP 0Ω 5 0402 YAGEO RC0402JR 070RL 19 2 STENCILS FOR BOTH SIDES DC1774A 2 DC1774A2 C Required Circuit Components 1 1 DC1774A 2 GENERAL BOM 2 0 C2 C4 CAP X7R 1000pF 50V 5 0402 AVX 04025C102JAT2A 3 0 C5 CAP X7R 1000pF 50V 5 0603 AVX 06035C10...

Страница 9: ...ZE DATE IC NO REV SHEET OF TITLE APPROVALS PCB DES APP ENG TECHNOLOGY Fax 408 434 0507 Milpitas CA 95035 Phone 408 432 1900 1630 McCarthy Blvd LTC Confidential For Customer Use Only CUSTOMER NOTICE LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER SUPPLIED SPECIFICATIONS HOWEVER IT REMAINS THE CUSTOMER S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE A...

Страница 10: ...CLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE EXCEPT TO THE EXTENT OF THIS INDEMNITY NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES The user assumes all responsibility and liability for proper and safe handling of the goods Further the user releases LTC from all claims arising from the handling or use of the g...

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