Design DocumentAnalog

Evaluation Board for the AD7191 Pin-Programmable, 24-Bit Sigma-Delta ADC (UG-280)

Evaluation board guide for the AD7191 24-bit Sigma-Delta ADC, featuring standalone LCD operation, USB PC software interface, and support for weigh scale applications.

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Overview

The UG-280 User Guide details the evaluation board for the Analog Devices AD7191, a pin-programmable 24-bit sigma-delta ADC. The board facilitates standalone operation using a microcontroller and LCD display, or PC-based control via a USB interface with provided software for real-time data logging and configuration. It includes onboard power regulation using ADP3303 regulators, an ADR421 precision reference, and specific headers for noise testing and load cell connections. The documentation covers hardware setup, power supply options (USB, battery, or external DC), standalone weigh scale demonstration, and software installation for performance evaluation.

Use Cases

Precision weigh scale design
Sensor signal conditioning
ADC performance characterization
Low-frequency data acquisition
Analog front-end prototyping

Topics

AD7191

Analog Devices

Evaluation Board

24-bit Sigma-Delta ADC

UG-280

ADR421

ADP3303

Precision Measurement

Weigh Scale Demo

USB Interface

Referenced Parts

AD5258BRMZ10

Analog Devices

U50 1 10 kΩ, 64-step digital potentiometer Analog Devices AD5258BRMZ10

AD7191BRUZ

Analog Devices

U1 1 AD7191 Analog Devices AD7191BRUZ

ADP3303ARZ-3.3

Analog Devices

U32 1 3.3 V voltage regulator Analog Devices ADP3303ARZ-3.3

ADP3303ARZ-5

Analog Devices

U31 1 5 V voltage regulator Analog Devices ADP3303ARZ-5

ADR421BRZ

Analog Devices

U2 1 ADR421 reference Analog Devices ADR421BRZ

MC1602C-SYR

Everbouquet

1 LCD module 2 × 16 char, 1 × 16-pin, top Everbouquet MC1602C-SYR

BSS138N

Infineon

Q51 1 N-MOSFET Infineon BSS138N

1613 14

Lumberg

J31 1 Connector, power jack, barrel, 2.1 mm, SMD Lumberg 1613_14

548190572

Molex

J51 1 Connector, USB Mini-B, SMD Molex 548190572

A6S-8102-H

Omron

S6 1 Switch, 8-way Omron A6S-8102-H

B3S-1000

Omron

S1 to S5 5 Switch Omron B3S-1000

1727010

Phoenix Contact

J10 1 Screw terminal block Phoenix Contact 1727010

1803332

Phoenix Contact

J4 1 1 × 8 way header Phoenix Contact 1803332

CX5032GB24000H0PESZZ

AVX

XTAL51 1 24 MHz crystal AVX CX5032GB24000H0PESZZ

TAJA106M016R

AVX

C17, C18, C25, C30 4 10 μF tantalum capacitor AVX TAJA106M016R

P6SMB68AT3G

Onsemi

D1 1 Diode ON Semiconductor P6SMB6.8AT3G

AD7191

Analog Devices

U1 1 AD7191 Analog Devices AD7191BRUZ

HSME-C191

Avago Technology

LED4 to LED8 5 LED green, high intensity (>50 mCd), 0603 Avago Technology HSME-C191

CY7C68013A-56LFXC

Cypress Semiconductor

U51 1 USB controller Cypress Semiconductor CY7C68013A-56LFXC

76341-308LF

FCI

U53 1 LCD connector FCI 76341-308LF

593+594

Keystone

B1 1 Clip for 9 V battery Keystone 593+594

24LC64-I/SN

Microchip Technology, Inc.

U52 1 64k I2 C EEPROM Microchip Technology, Inc. 24LC64-I/SN

BAT721C

Philips

D31 to D34 4 Diode Philips BAT721C

2238 246 13663

Phycomp

C9, C12, C14 3 1 μF ceramic capacitor Phycomp 2238 246 13663

2238 586 15636

Phycomp

C8, C10, C11, C13 4 0.01 μF ceramic capacitor Phycomp 2238 586 15636

2238 786 15649

Phycomp

C19 to C24, C31 to C33, C50, C54 to C61 18 0.1 μF ceramic capacitor Phycomp 2238 786 15649

2238 867 15129

Phycomp

C52, C53 2 12 pF ceramic capacitor Phycomp 2238 867 15129

2255 206 13672

Phycomp

C34 to C38, C51 6 4.7 μF ceramic capacitor Phycomp 2255 206 13672

232270296001

Phycomp

R1, R2 2 0 Ω resistor Phycomp 232270296001

232270461001

Phycomp

R3 to R4, R8, R20 to R25, R54 10 100 Ω resistor Phycomp 232270461001

232270461002

Phycomp

R6, R7, R52, R53 4 1 kΩ resistor Phycomp 232270461002

232270461003

Phycomp

R12 to R15, R19, R50 10 100 kΩ resistor Phycomp 232270461003

232270461004

Phycomp

R18, R31 to R37, R55 to R57, R61 to R70, R72, R73 23 100 kΩ resistor Phycomp 232270461004

232270461009

Phycomp

R58, R59 2 10 Ω resistor Phycomp 232270461009

232270461508

Phycomp

R16 1 1.5 Ω resistor Phycomp 232270461508

232270464709

Phycomp

R74 1 47 Ω resistor Phycomp 232270464709

1-826629-6

Tyco

1 LCD header Tyco 1-826629-6

BMB2A1000LN2

Tyco

L1 1 Ferrite bead Tyco BMB2A1000LN2

1241050-4

Tyco/Amp

J1 1 2 × 4 way header Tyco/Amp 1241050-4

1241050-8

Tyco/Amp

J2, J3 2 2 × 8 way header Tyco/Amp 1241050-8

AD5258BRMZ10	Analog Devices	U50 1 10 kΩ, 64-step digital potentiometer Analog Devices AD5258BRMZ10
AD7191BRUZ	Analog Devices	U1 1 AD7191 Analog Devices AD7191BRUZ
ADP3303ARZ-3.3	Analog Devices	U32 1 3.3 V voltage regulator Analog Devices ADP3303ARZ-3.3
ADP3303ARZ-5	Analog Devices	U31 1 5 V voltage regulator Analog Devices ADP3303ARZ-5
ADR421BRZ	Analog Devices	U2 1 ADR421 reference Analog Devices ADR421BRZ
MC1602C-SYR	Everbouquet	1 LCD module 2 × 16 char, 1 × 16-pin, top Everbouquet MC1602C-SYR
BSS138N	Infineon	Q51 1 N-MOSFET Infineon BSS138N
1613 14	Lumberg	J31 1 Connector, power jack, barrel, 2.1 mm, SMD Lumberg 1613_14
548190572	Molex	J51 1 Connector, USB Mini-B, SMD Molex 548190572
A6S-8102-H	Omron	S6 1 Switch, 8-way Omron A6S-8102-H
B3S-1000	Omron	S1 to S5 5 Switch Omron B3S-1000
1727010	Phoenix Contact	J10 1 Screw terminal block Phoenix Contact 1727010
1803332	Phoenix Contact	J4 1 1 × 8 way header Phoenix Contact 1803332
CX5032GB24000H0PESZZ	AVX	XTAL51 1 24 MHz crystal AVX CX5032GB24000H0PESZZ
TAJA106M016R	AVX	C17, C18, C25, C30 4 10 μF tantalum capacitor AVX TAJA106M016R
P6SMB68AT3G	Onsemi	D1 1 Diode ON Semiconductor P6SMB6.8AT3G
AD7191	Analog Devices	U1 1 AD7191 Analog Devices AD7191BRUZ
HSME-C191	Avago Technology	LED4 to LED8 5 LED green, high intensity (>50 mCd), 0603 Avago Technology HSME-C191
CY7C68013A-56LFXC	Cypress Semiconductor	U51 1 USB controller Cypress Semiconductor CY7C68013A-56LFXC
76341-308LF	FCI	U53 1 LCD connector FCI 76341-308LF
593+594	Keystone	B1 1 Clip for 9 V battery Keystone 593+594
24LC64-I/SN	Microchip Technology, Inc.	U52 1 64k I2 C EEPROM Microchip Technology, Inc. 24LC64-I/SN
BAT721C	Philips	D31 to D34 4 Diode Philips BAT721C
2238 246 13663	Phycomp	C9, C12, C14 3 1 μF ceramic capacitor Phycomp 2238 246 13663
2238 586 15636	Phycomp	C8, C10, C11, C13 4 0.01 μF ceramic capacitor Phycomp 2238 586 15636
2238 786 15649	Phycomp	C19 to C24, C31 to C33, C50, C54 to C61 18 0.1 μF ceramic capacitor Phycomp 2238 786 15649
2238 867 15129	Phycomp	C52, C53 2 12 pF ceramic capacitor Phycomp 2238 867 15129
2255 206 13672	Phycomp	C34 to C38, C51 6 4.7 μF ceramic capacitor Phycomp 2255 206 13672
232270296001	Phycomp	R1, R2 2 0 Ω resistor Phycomp 232270296001
232270461001	Phycomp	R3 to R4, R8, R20 to R25, R54 10 100 Ω resistor Phycomp 232270461001
232270461002	Phycomp	R6, R7, R52, R53 4 1 kΩ resistor Phycomp 232270461002
232270461003	Phycomp	R12 to R15, R19, R50 10 100 kΩ resistor Phycomp 232270461003
232270461004	Phycomp	R18, R31 to R37, R55 to R57, R61 to R70, R72, R73 23 100 kΩ resistor Phycomp 232270461004
232270461009	Phycomp	R58, R59 2 10 Ω resistor Phycomp 232270461009
232270461508	Phycomp	R16 1 1.5 Ω resistor Phycomp 232270461508
232270464709	Phycomp	R74 1 47 Ω resistor Phycomp 232270464709
1-826629-6	Tyco	1 LCD header Tyco 1-826629-6
BMB2A1000LN2	Tyco	L1 1 Ferrite bead Tyco BMB2A1000LN2
1241050-4	Tyco/Amp	J1 1 2 × 4 way header Tyco/Amp 1241050-4
1241050-8	Tyco/Amp	J2, J3 2 2 × 8 way header Tyco/Amp 1241050-8