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dc1925af

DEMO MANUAL DC1925A

DC1925A JUMPERS

Definitions
JP1
 – EEPROM is for factory use only. Leave this in the 

default WP position.
JP2 – V+ Selects 8V or 5V for V+. The default is position 

is 8V. Setting V+ to 5V is useful for evaluating single 5V 

supply operation of the buffer when operating the ADC 

with Digital Gain Compression turned on.
JP3 – VCCIO sets the output levels at P1 to either 3.3V 

or 2.5V. Use 2.5V to interface to the DC890 which is the 

default setting. Use 3.3V to interface to the DC590.
JP4 – VCM sets the DC bias for AIN+ and AIN– if the single 

ended to differential mode is enabled, and the inputs are 

AC coupled. V

REF

/2 is the default setting.

JP5 – V– Selects –3.6V or ground for V–. The default set-

ting is –3.6V. Setting V– to ground is useful for evaluating 

single supply operation of the buffer when operating the 

ADC with Digital Gain Compression turned on.
JP6 – FS selects whether the Digital Gain Compression is 

on or off. In the VREF position, Digital Gain Compression 

is off and the analog input range at A

IN

+ and A

IN

– is 0V to 

V

REF

. In the 0.8VREF position, Digital Gain Compression is 

turned on and the analog input range at A

IN

+ and A

IN

– is 

0.1V

REF

 to 0.9V

REF

. The default setting is off.

JP7 – Coupling selects AC or DC coupling of A

IN

+. The 

default setting is DC. 
JP8 – Coupling selects AC or DC coupling of A

IN

–. The 

default setting is DC.

Summary of Contents for DC1925A Series

Page 1: ...ing on the information therein All referenced brands product names service names and trademarks are the property of their respective owners 00000005981LF 000 EOS Power Buy Now We have 45 000 LP502030 PCM NTC LD A02554 EEMB Lithium Battery Rectangular 3 7V 250mAh Rechargeable in stock now Starting at 0 034 This EEMB part is fully warrantied and traceable 1 855 837 4225 Give us a call International ...

Page 2: ...LTC2378 20 in conjunction with the DC590 QuikEval and DC890 PScope data collection boards Use the DC590 to demonstrate DC performance such as L LT LTC LTM Linear Technology and the Linear logo are registered trademarks and QuikEval and PScope are trademarks of Linear Technology Corporation All other trademarks are the property of their respective owners BOARD PHOTO Figure 1 DC1925A Connection Diag...

Page 3: ...te that J1 has a 50Ω termination resistor to ground Run the PScope software PScope exe version K73 or later supplied with the DC890 or download it from www linear com software Complete software documentation is available from the Help menu Updates can be downloaded from the Tools menu Check for updates periodically as new features may be added The PScope software should recognize the DC1925A and c...

Page 4: ...ssing is desired Alternatively the data can be fed directly into an application circuit Use Pin 50 of P1 to latch the data The data can be latched using either edge of this signal The data output signal levels at P1 can also be changed to 0V to 3 3V if the application circuit requires a higher voltage This is accomplished by moving VCCIO JP3 to the 3 3V position Reference The default reference is ...

Page 5: ...on is feeding the converter with a frequency that is a sub multiple of the sample rate and which will only exercise a small subset of the possible output codes The proper methodistopickanM Nfrequencyfortheinputsinewave frequency N is the number of samples in the FFT M is a prime number between one and N 2 Multiply M N by the sample rate to obtain the input sine wave frequency Another scenario that...

Page 6: ...8 20 component selection is important so as to not degrade performance Resistors should have low values to minimize noise and distortion Metal film resistors are recommended to reduce distortion caused by self heating Because of their low voltage coefficients to further reduce distortion NPO or silver mica capacitors should be used Any buffer used to drive the LTC2378 20 should have low distortion...

Page 7: ...6 dc1925af DEMO MANUAL DC1925A DC1925A SETUP Figure 6 QuikEval Screen Shot ...

Page 8: ...differential mode is enabled and the inputs are AC coupled VREF 2 is the default setting JP5 V Selects 3 6V or ground for V The default set ting is 3 6V Setting V to ground is useful for evaluating single supply operation of the buffer when operating the ADC with Digital Gain Compression turned on JP6 FS selects whether the Digital Gain Compression is on or off In the VREF position Digital Gain Co...

Page 9: ...VX 06036D475MAT2A 17 7 E1 E2 E3 E4 E5 E9 E10 TEST POINT TURRET 0 061 MILL MAX 2308 2 00 80 00 00 07 0 18 3 E6 E7 E8 TESTPOINT TURRET 0 094 PBF MILL MAX 2501 2 00 80 00 00 07 0 19 8 JP1 JP8 HEADER 3 PIN SINGLE ROW 0 100 SAMTEC TSW 103 07 L S 20 3 J1 J2 J4 CONNECTOR BNC CONNEX 112404 21 1 J3 CONN HEADER 14 POS 2MM VERT GOLD MOLEX 87831 1420 22 1 J5 HEADER 2X5 0 100 SAMTEC TSW 105 07 L D 23 4 MH1 MH2...

Page 10: ... IC SERIAL EEPROM TSSOP MICROCHIP 24LC024 I ST 52 2 U8 U9 IC UHS INVERTER SC70 5 FAIRCHILD NC7SZ04P5X 53 2 U10 U18 IC DUAL OP AMP MS8 LINEAR TECH LT6203CMS8 PBF 54 1 U11 IC MAX II CPLD TQFP100 ALTERA EPM240GT100C5N 55 1 U12 IC MICROPOWER REGULATOR SO 8 LINEAR TECH LT1763CS8 1 8 PBF 56 2 U13 U16 IC MICROPOWER REGULATOR SO 8 LINEAR TECH LT1763CS8 PBF 57 1 U14 IC MICROPOWER REGULATOR SO 8 LINEAR TECH...

Page 11: ...10 dc1925af DEMO MANUAL DC1925A SCHEMATIC DIAGRAM ...

Page 12: ...logy Corporation is believed to be accurate and reliable However noresponsibilityisassumedforitsuse LinearTechnologyCorporationmakesnorepresenta tion that the interconnection of its circuits as described herein will not infringe on existing patent rights SCHEMATIC DIAGRAM ...

Page 13: ...UDING 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 goo...

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