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Features

1-2

General Information

1.1

Features

THS7001 programmable-gain amplifier EVM features include:

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Multiple Input Configurations Set Via On Board Jumpers

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DIP Switches Allow Quick and Easy Adjustment of Gain, Shut Down,
Reference Voltage, and Output Clamping

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Standard BNC Connector Inputs and Outputs

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±

5-V to 

±

15-V Operation With 5-V Reference Input

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Nominal 50-

 Impedance Inputs and Outputs

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Includes Test Points for Easy Digital Control of EVM Circuit Gain and
Operating Parameters

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Good Example of PowerPAD Package and High-Speed Amplifier
Design and Layout

1.2

Description

The TI THS7001 programmable-gain amplifier evaluation module (EVM) is a
complete low-noise receiver and a highly configurable programmable-gain
amplifier circuit. It consists of the TI THS7001 programmable-gain amplifier IC
and a number of passive parts, all mounted on a multilayer circuit board
(Figure 1–1).

Although the THS7001 IC was developed primarily for xDSL receiver
front-ends, a large number of different circuits can benefit from the many
features incorporated into the THS7001. This EVM illustrates a universal
design and can be used for numerous system configurations.

The EVM uses standard BNC connectors for inputs and outputs and also
includes test points for user connections and testing. It is completely
assembled, fully tested, and ready to use—just connect it to power, a signal
source, and a load (if desired).

Summary of Contents for THS7001

Page 1: ...THS7001 Programmable Gain Amplifier Evaluation Module December 1999 Mixed Signal Products User s Guide SLOU057...

Page 2: ...ONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH PERSONAL INJURY OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE CRITICAL APPLICATIONS TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED AUTHORIZED OR WARRANT...

Page 3: ...in a laboratory test environment only It generates uses and can radiate radio frequency energy and has not been tested for compliance with the limits of computing devices pursuant to subpart J of par...

Page 4: ...iv...

Page 5: ...1 4 EVM DIP Switch Functionality 1 8 1 5 EVM Circuit Configuration 1 9 1 6 Using The THS7001 EVM 1 10 1 7 THS7001 EVM Performance 1 11 1 8 General High Speed Amplifier Design Considerations 1 14 1 9...

Page 6: ...e VCC 5 V 1 12 1 9 THS7001 EVM Preamplifier PGA Response VCC 15 V 1 13 1 10 THS7001 EVM Preamplifier PGA Response VCC 5 V 1 13 1 11 PowerPAD PCB Etch and Via Pattern 1 15 1 12 Maximum Power Dissipatio...

Page 7: ...nfiguring connecting and using the EVM and a discussion on high speed amplifier and PowerPAD package design considerations Topic Page 1 1 Features 1 2 1 2 Description 1 2 1 3 Programmable Gain Amplifi...

Page 8: ...rogrammable gain amplifier evaluation module EVM is a complete low noise receiver and a highly configurable programmable gain amplifier circuit It consists of the TI THS7001 programmable gain amplifie...

Page 9: ...JP1 R6 C6 R20 C7 C12 R2 R41 R23 R25 R27 R29 R31 JP2 C8 1999 Texas Instruments J4 J3 J2 J1 SLOP250 THS7001 EVM Board R8 GND 1 R7 C1 C3 R1 A C13 C14 Input power is applied to the EVM through banana jac...

Page 10: ...TP8 S D TP7 C19 0 1 F 15 V R23 330 R25 330 R27 330 R24 3 3 k R26 3 3 k R28 3 3 k 3 2 1 TP5 VH R41 49 9 R42 4 7 k R31 49 9 R32 4 7 k R44 100 J9 PGA A Output VL TP6 S1 F 15 V 5 V 15 V JP3 G2 TP3 C17 0 1...

Page 11: ...can easily be changed to support different applications by changing the resistor ratios Although any of the components on the EVM board can be replaced with different values it is imperative that the...

Page 12: ...PGA Gain dB PGA Gain V V 0 0 0 22 0 08 0 0 1 16 0 16 0 1 0 10 0 32 0 1 1 4 0 63 1 0 0 2 1 26 1 0 1 8 2 52 1 1 0 14 5 01 1 1 1 20 10 One aspect of the THS7001 PGA signal input that must be considered...

Page 13: ...linear input range and saturation characteristics of most ADCs the PGA output incorporates a voltage clamp These clamps are typically connected to the power supply pins to allow a full output range Ho...

Page 14: ...onality SWITCH LABEL POSITION DESCRIPTION S1 A A G0 0 PGA Gain Bit 0 LSB Value 0 Low S1 A A G0 1 PGA Gain Bit 0 LSB Value 1 High S1 B A G1 0 PGA Gain Bit 1 Value 0 Low S1 B A G1 1 PGA Gain Bit 1 Value...

Page 15: ...2 Jumper JP1 J 1 2 Connects the input of the PGA U1 B to the input A BNC J6 bypassing the THS7001 preamplifier U1 A J 2 3 Connects the input of A channel PGA U1 B to the output of the A channel pream...

Page 16: ...onnect an oscilloscope probe to the PGA A amplifier output BNC J9 Connecting directly to J9 with a 50 nominal impedance cable and probe is not recommended The output drive capability of the PGA is ver...

Page 17: ...ndwidth of the preamplifier with a 15 V power supply is 100 MHz and 90 MHz with a 5 V power supply Figure 1 5 THS7001 EVM Preamplifier Response VCC 15 V f Frequency Hz 100k 1M 10M 100M 6 4 2 7 5 3 1 5...

Page 18: ...2 dB Typical 3 dB bandwidth is 70 MHz with a 5 V power supply and 80 MHz with a 15 V power supply Figure 1 7 THS7001 EVM PGA Response VCC 15 V f Frequency Hz 100k 1M 10M 100M 3 1 1 4 2 0 2 500M VO 0 4...

Page 19: ...input The PGA was set to a gain of 2 dB Typical 3 dB bandwidth is 70 MHz with a 5 V power supply and 80 MHz with a 15 V power supply Figure 1 9 THS7001 EVM Preamplifier PGA Response VCC 15 V f Freque...

Page 20: ...ce and reduce ground plane noise coupling into these pins This is especially important for the inverting pin while the amplifier is operating in the noninverting mode Because the voltage at this pin s...

Page 21: ...rmal pad Figure 1 11 PowerPAD PCB Etch and Via Pattern Thermal pad area 0 12 x 0 17 with 8 vias Via diameter 13 mils 2 Place 8 holes in the area of the thermal pad These holes should be 13 mils in dia...

Page 22: ...depends on the application In the example above if the size of the internal ground plane is approximately 3 inches 3 inches then the expected thermal coefficient JA is about 32 6_C W For a given JA th...

Page 23: ...roper thermal management when using PowerPAD mounted devices Correct PCB layout and manufacturing techniques are critical for achieving adequate transfer of heat away from the PowerPAD IC package More...

Page 24: ...Input voltage VI VCC max Output drive THS7001 Preamplifier IO 95 mA typ Output drive THS7001 PGA IO 50 mA typ Continuous total power dissipation at TA 25 C 3 8 W max For complete THS7001 amplifier IC...

Page 25: ...ence This chapter includes a parts list and PCB layout illustrations for the THS7001 EVM Topic Page 2 1 THS7001 Dual Differential Line Drivers and Receivers EVM Parts List 2 2 2 2 THS7001 EVM Board La...

Page 26: ...NG JUMPERS 0 1 CTRS FOR 0 025 SQ PINS 3 SW1 6PST DIP SWITCH CTS 219 NST Series Gold Finish 1 DIGI KEY CT2196MST ND R6 RESISTOR 0 1 8 W 1 SM 0805 1 R18 R31 R41 RESISTOR 49 9 1 10 W 1 SM 0805 3 R5 R9 RE...

Page 27: ...1 EVM Board Layouts Board layout examples of the THS7001 EVM PCB are shown in the following illustrations They are not to scale and appear here only as a reference Figure 2 1 THS7001 EVM PC Board Top...

Page 28: ...THS7001 EVM Board Layouts 2 4 Reference Figure 2 3 THS7001 EVM PC Board Bottom Layer Top VIew...

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