Nexus Lite Raspberry Pi IO HAT with relays shown mounted on a Pi.

AQEX Synapse Nexus Lite: Essential Raspberry Pi IO Module for Simple Tasks

Essential I/O expansion for your Raspberry Pi without the overkill. A cost-effective, professional control board engineered with isolated inputs and relays for straightforward automation and smart home tasks.

Built for Developers & Industrial Systems - Developer-Centric Hardware (DCH).

Right-Sized Architecture: Designed for focused projects where you only need essential inputs and relays without paying for unused channels.

Electrical Isolation: Built-in optical protection to safeguard your Raspberry Pi from power surges and noise.

Professional Connectivity: Reliable screw terminals for secure, durable wiring in compact spaces.

Zero-Configuration Integration: Built-in Home Assistant Auto-MQTT Discovery for instant setup.

Jump iconLearn About Our Approach

The Objective Behind Synapse Nexus Lite

Nexus Lite Raspberry Pi IO HAT : Clearly visible I/O terminals & relays.

Driven by our Developer-Centric Hardware (DCH) philosophy, we set out to eliminate the cost and bulk of oversized modules for projects where fewer channels are exactly enough.
Most Raspberry Pi I/O boards force you to pay for unused capacity. By focusing strictly on 2 opto-isolated inputs and 2 relay outputs, combined with professional-grade protection and built-in Home Assistant Auto-MQTT Discovery, we created a compact, budget-friendly control solution. Whether you are automating a small setup or tackling a straightforward task, you get uncompromising safety and zero code configuration without paying for extra ports.

Design Choices for Synapse Nexus Lite

Form icon

From Factor

For easy assembly, Nexus Lite has HAT form factor. Simply connect it via the 40 pin header.

Stackablility icon

Stackability

Pins on the connector are long ones, all can be accessed from the top of the product.

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Reliable connection

Massive, soldered pin header for power and signal connection. Pogo pins are not reliable.

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High quality IO connectors

All IO connectors are high quality, vibration-resistant spring terminals.

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Zero firmware

Everything is done by hardware.

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GPIO communication

Easy programming. Avoid extra load on capacitance limited I2C bus. Only 4 GPIO ports for communication.

Isolation icon

Optical isolation

Optically isolated channels safeguard your Raspberry Pi from electrical noise and damage.

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Wide input voltage range

3-45V range for level type inputs.

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Versatile SPDT Relays

Each relay features both Normally Open (NO) and Normally Closed (NC) contacts, letting you choose how to control your circuits.

Pin allocation of the Synapse Nexus Lite

Input 1/17
Input 2/27
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Relay Out 1/14
Relay Out 2/15

Synapse Nexus Lite User Interface and Indicators

Nexus Lite top view: Clearly visible I/O terminals relays.
Raspberry Pi 2x20 pin connector
1
Relays
2
Output connectors
3
Input connectors
4

1 - Raspberry Pi 2x20 pin connector
2 - Relays
3 - Output connectors
4 - Input connectors

Technical Specs of the Synapse Nexus Lite

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Physical parameters

Form factor
Raspberry Pi HAT
Dimensions
65x56x17mm + 11mm header
Stackable
Yes
Input iconInputs
Number of input
2
Input types
Level
Input voltage range
3-45V
Output iconOutputs
Number of outputs
2
Output type
Relay
Relay type
SPDT
Max voltage
240VAC, 24VDC
Max current resistive
7A
Max current inductive
3A
Connector iconConnectors
Connection type
Spring terminal
Vibration resistant
Yes
Communication iconCommunication
Method
GPIO ports
Used GPIO ports for input
2
Used GPIO ports for output
2
Helmet iconSafety
Optical isolation
Yes
Software iconSoftware
Control software
C++ & Python
Open Source
Yes
Home Assistant compatibility
Auto-MQTT Discrovery

Synapse Nexus Lite Home Assistant Integration

Home Assistant integration steps:

Open the Github page:
 https://github.com/aqexhu/synapse/tree/main/src

Download the driver and sample file:
 qpio-ha & sample-config-nexus-lite.json

Update the MQTT parameters in the json file:
  broker, port, username, password

Rename the json file, if you want

Start the driver

qpio-ha --config xxx.json

Synapse Nexus Lite Gallery

Synapse Nexus Lite 3D view & Model

Purchase Options for Synapse Nexus Lite

Synapse Nexus Lite Manuals & Resources