ADALM-MMSC

Mixed-Mode Signal Chain Active Learning Module

Overview

Figure 1 ADALM-MMSC Board

The Analog Devices Active Learning Module-Mixed-Mode Signal Chain (ADALM-MMSC) is an educational board designed to facilitate hands-on exploration of fundamental signal chain concepts.

The core of the circuit is the AD4080, a 40 MSPS oversampling SAR analog-to-digital converter (ADC) with a configurable digital filter and internal data capture memory (single-port FIFO).

The board includes a highly configurable 2nd order analog filter with adjustable cutoff frequencies, input attenuation, and filter gain.

An onboard selectable clock source provides sample rates from 5 MSPS to 40 MSPS. A MAX32666FTHR microcontroller runs an IIO server over a serial backend, allowing the use of standard tools such as Scopy, IIO Oscilloscope, Pyadi-iio, and ADI’s MATLAB precision toolbox.

The Libiio library provides language bindings for C, C#, MATLAB®, Python, and other languages.

Concepts demonstrated include:

• Digital filtering

• Analog vs. digital anti-alias filtering

• Properties of different digital filters

• Noise analysis

• Reference noise

Features

• Multiple input connections

  • 100-mil posts compatible with the ADALM2000

  • SMA connections for benchtop signal generators

  • 1/8-inch stereo audio jack for connection to sound cards and other audio sources

• Selectable input attenuator

  • 3:5 attenuation allows ±5V input swing

  • 3:50, 3:500 attenuation settings allow testing with low-amplitude signals for dynamic range measurements

• Configurable Sallen-Key filter with low-noise amplifier

  • Cutoff frequencies between 200 kHz and 8 MHz

  • Gains of unity, 2, and 5 for exploring noise optimization

• Onboard fully-differential amplifier

  • Accepts arbitrary input signals

  • Input and output test connections for monitoring all critical points

• Onboard low-noise reference

  • Flagship LTC6655 for optimal performance

  • “Reference Corruption” input allows noise and interfering tones to be introduced and their effects observed

• Selectable conversion rates from 5 MSPS to 40 MSPS allow observation of aliasing and ADC noise density vs. sample rate

Applications

• Mixed signal and digital signal processing experiments, workshops, and lab exercises

• Precision data acquisition

System Architecture

Figure 2 ADALM-MMSC Simplified Block Diagram

Package Contents

The ADALM-MMSC kit includes the following boards and accessories:

Figure 3 ADALM-MMSC Kit Contents

• (A.) 1x ADALM-MMSC Board

• (B.) 1x Pre-programmed MAX32666FTHR board

• (C.) 1x USB-A to Micro-USB cable

• (D.) 1x MAX32625PICO with 10-pin ribbon cable for SWD connection (for future firmware upgrades)

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Components and Connections

Figure 4 ADALM-MMSC Primary Side

Figure 5 ADALM-MMSC Secondary Side

Table 1 Jumper Configurations

Jumper	Function	Default Setting
P15	Input attenuation	1-2 (5:3 attenuation, +/-5V full-scale)
P10	Positive FDA input	1-2 (Direct connection)
P12	Negative FDA input	2-3 (Ground)
P5	Filter RA	1-2 (RAL, 1.2k total)
P8	Filter RB	1-2 (RBL, 1.2k)
P16	Filter CI	1-3 (not connected)
P14	Filter CF	1-3 (not connected)
P11	Gain select	1-3 (unity gain)
P9	FDA Mode	1-2 (full power mode)
P29, P30	Extra CIN	Not installed
P23	Ref Disturbance Bypass	Not installed

Table 2 Connection Descriptions

Connection	Function	Range
P17	Fly-wire/m2k input	Pin 1: +/-3 V, +/-5 V when P10 set to filter path
		Pin 2: +/-3 V
J1	IN+	+/-3 V, +/-5 V when P10 set to filter path
J2	IN-	+/-3V
P4	Phono input	Left (tip): +/-3 V, +/-5 V when P10 set to filter path
		Right: +/-3 V
P24	Reference interference input	+/- 5V
P6	FDA input	For monitoring only
P7	FDA output	For monitoring only

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Quick Start

There are numerous combinations of signal sources, signal analyzers, and software that can be used with the ADALM-MMSC. The most straightforward approach to get up and running and establish baseline functionality is to use the ADALM2000 with Scopy. Scopy is a general-purpose IIO-based utility with instrument-specific control panels for various hardware, including the ADALM2000.

Equipment Needed

• 1x ADALM-MMSC Board (as Device Under Test)

• Windows, Mac, or Linux host computer with an available USB port

• Signal generator such as the ADALM2000 or similar Alternative signal sources include:

  • Generators in the audio range work well

  • A PC sound card with Audacity is another option

Hardware Setup

The hardware setup uses the ADALM2000 (M2K) as the primary signal source for the system, as shown in the image below. In this configuration, the M2K’s waveform generator outputs are connected to the designated input pins on the ADALM-MMSC board, allowing the board to receive and process test signals.

Figure 6 ADALM2000 (M2K) to ADALM-MMSC Hardware Setup

1. Connect the two black GND wires from the ADALM2000 to the lower two posts of P17 (Pins 3 and 4).

2. Connect the solid yellow W1 wire from the ADALM2000 to P17 Pin 1.

3. Connect the striped yellow W2 wire from the ADALM2000 to P17 Pin 2.

4. Connect both the ADALM2000 and the ADALM‑MMSC to the host computer using two micro‑USB cables.

5. Set P10 to the lower position (DIR) and P12 to the upper position (DIR). This configuration bypasses the Sallen‑Key filter and applies the inputs directly to the fully differential amplifier.

Software Setup

Requirement:

Download

Scopy: latest version (user guide)

1. Connect the ADALM‑MMSC to the host computer using a USB‑A to USB‑Micro cable, then open the Scopy GUI.

2. If you are using the ADALM2000, connect the instrument and allow the calibration process to complete.

3. From the Scopy home screen, add the ADALM‑MMSC connection by clicking the + button, as shown in the figure below.

   

   Figure 7 Adding the ADALM‑MMSC in Scopy

4. Click the Scan button and select the ADALM‑MMSC serial port. More than one serial port may be listed, depending on the devices connected to the host machine.

   

   Figure 8 Scanning for the ADALM‑MMSC Serial Port

5. Click Verify, then click Add Device.

   

   Figure 9 Verifying the ADALM‑MMSC Connection

6. From the Scopy home screen, click Connect.

   

   Figure 10 Connecting to the ADALM‑MMSC in Scopy

7. Once connected, Scopy is ready to acquire data from the ADALM-MMSC.

   1. Open the ADC Time panel.

   2. Set the buffer size to 4096 (maximum is 16384, limited by the AD4080 FIFO depth).

   3. Click Start.

8. The figure below shows the ADC output when the signal generator is configured as follows:

   • Channel 1: 1 Vpp, 500 kHz sine wave

   • Channel 2: 1 Vpp, 50 kHz sawtooth

   

   Figure 11 ADC Time Domain Capture in Scopy

9. Refer to the supporting lab exercises and workshop materials for additional experiments.

Firmware Upgrades

1. Access the ADALM‑MMSC firmware source from the no‑OS repository:

   ADALM‑MMSC firmware (no‑OS).

2. Download the pre‑built firmware binaries from the no‑OS releases page:

   ADALM‑MMSC releases

   The firmware package is provided as adalm-mmsc.zip.

3. Use the included MAX32625PICO board to upgrade the firmware.

4. Follow the instructions in the MAX32625PICO firmware images repository to load the MAX32666FTHR‑specific binary:

   MAX32625PICO firmware images

5. Connect the 10‑pin ribbon cable between the MAX32625PICO and the MAX32666FTHR board.

6. Drag and drop the file adalm-mmsc_maxim_iio_example_max32665.hex into the DAPLINK drive (typically D:\ or E:\ on Windows).

7. Wait for the DAPLINK drive to automatically eject, indicating that the firmware upgrade has completed successfully.

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Resources

Design & Integration Files

Download

ADALM-MMSC Design & Integration Files

• Schematic

• PCB Layout

• Bill of Materials

• Allegro Project

Schematic Errata

The value of R44 is 499 Ohms (not 1.33K as shown in the schematic)

Helpful Links

• AD4080 Product Page

• ADA4945-1 Product Page

• ADM1085 Product Page

• LT1468 Product Page

• LT3042 Product Page

• LT3093 Product Page

• LT3471 Product Page

• LTC6655 Product Page

• MAX38912 Product Page

• ADALM2000 Product Page

• Scopy Overview

Support

For questions and more information, please visit the EngineerZone Support Community.