EEZ DIB MUX14D dual 2-wire 7:1 (14:1) Multiplexer
Work in progress
Yes (TME, Mouser, Digikey, Farnell, RS)
(include Eagle, Gerber and BOM files)
- On-board STM32F030C6T6 ARM Cortex-M0 Value line MCU, 32 KiB Flash, 48 MHz CPU, LQFP-48 package
- 2 x 16-pin dual row 3.81 mm connectors
- 2 x ADIB connectors (10-pin 2 mm)
- Dual 2-wire 1:7 reed relay multiplexer switchable to 1:14 multiplexer
- “Cold junction” temperature sensor
- On-board +3.3 V LDO
- Firmware download via UART
- Optional SWD for debugging
- I2C EEPROM for storing board specific parameters
- Dimensions: 131 x 95 mm, 2-layer PCB
The MUX14D module features dual 2-wire 7:1 reed relay multiplexer that can be combined in single 14:1 multiplexer. Multiplexer output is exposed on front panel terminal or can be connected (firmware controlled) to ADIB that offer internal wiring with other modules (e.g. MIO168).
The module has two 16-pin 3.81 mm connectors on the front panel thanks to which it is possible to quickly and easily connect the wires without the need for an additional breakout box. 8-way pluggable female terminal connector blocks in low-profile push-in and screw-fasten variants can be used to connect the wires.
EEZ DIB interface
The SMX46 module interface with the MCU module is accomplished over the 28-pin 0.1” right angled header (X2).
On-board I2C EEPROM (IC3) provides storage for module-specific information such as its ID, analog outputs calibration data, working hours counters and relay switch cycles. Its address is defined by RN2-2 to RN2-4 pull-up resistors and ground connections on the backplane.
The STM32F030C6T6, a mainstream ARM Cortex-M0 Value line MCU with 32 KiB Flash, 48 MHz (IC1) is used to control power relays and to communicate with the master MCU on the MCU module.
UART and BOOT0 are used to program its flash memory, a process that is controlled by the master MCU and can be easily done via a touchscreen screen without the need for an external programmer/ debugger (ST-Link or similar). 3-state buffer (IC2) is used to control the UART TX output which can only be active while downloading the firmware to flash memory.
The powering of the MCU and all logic is done via 3.3 V LDO (IC4) which uses +5 V from DIB.
Two 10-pin 2.0 mm ADIB connectors (X3, X4) are used for internal connectivity with other modules (e.g. MIO168): P1 multiplexer output could be connected to ADIB #1 and P2 output to ADIB #2. MUX14D ADIB ID is set to 002.
Reed relay multiplexers
Dual 2-wire 7:1 multiplexers are accomplished with two group of low power reed relays (K1-K7 and K10-K16). Multiplexer outputs are exposed to front panel terminals (pin X6-15, X6-16 and X6-7, X6-8). Outputs could be selectively applied to ADIB connectors that provides internal wiring to other DIB modules equipped with ADIB connections.
Multiplexer outputs can be combined to make a single 14:1 multiplexer by using to K8 relay.
Two 8-port darlington drivers (IC7, IC8) are used to drive two group of reed relays (K1,K3, K6, K8, K12, K14, K16, K9 and K2, K4, K7, K10, K13, K15, K17, K11). Selected drivers feature protection diodes whose common outputs are connected using zener diodes (ZD1, ZD2) at +5 V.
The remaining relay (K5) has a separate driver (Q1) with protection diodes (D1, ZD3).
“Cold junction” temperature sensor
The module also has a "cold junction" sensor for temperature compensation in case thermocouple sensors are connected to the inputs. The output voltage of the LM335A (1% error) sensor used gives 10 mV/K or about 2.93 V for room temperature (20 degrees Celsius). This voltage was applied to an attenuating operational amplifier (IC5) to extend the temperature range from 0 to 55 degrees Celsius to approximately the full scale of the ADC in the MCU (i.e. 400 mV to 3.2 V) for better measurement accuracy.
Table of content
- DIB BP3C backplane
- DIB AUX Power Supply
- DIB STM32F7 MCU module
- DIB DCP405 Power module
- DIB DCM220 Dual output power module
- DIB DCM224 auxiliary power module
- DIB SMX46 switch matrix module
- DIB PREL6 power relays module
- EEZ DIB MIO168 Mixed I/O module
- DIB MIO168 AFE1
- DIB MIO168 AFE2
- DIB MIO168 AFE3
- MUX14D 2-wire dual 7:1 (14:1) Multiplexer
- Specification and comparison with the EEZ H24005
- Wire harness
- User Manual
- 1. Introduction
- 2. Key features
- 3. Operation Environment
- 4. Unpacking and Checking the EEZ BB3
- 5. Overview
- 6. Getting started
- 7. Basic operations
- 8. System settings
- 9. System functions
- 10. Channel protections
- 11. Special channel functions
- 12. Power modules calibration
- 13. Firmware upgrade
- 14. Data logging
- 15. MQTT
- 16. Scripting with MicroPython
- 17. Node-RED integration
- SCPI reference manual
- 1. Introduction
- 2. Syntax and style
- 3. Registers and queues
- 4. Common command reference
- 5. Subsystem command reference
- 6. Device-specific (unclassified) commands
- 7. Error messages
- 8. Parameters and settings
- 9. Software simulator
- 10. Programming examples
- 11. SCPI commands scheduled for upcoming releases
- 12. SCPI commands summary
- Building instructions
- Firmware and scripts