SwitchBlox 5V Output Performance

Jul 16, 2021

4 min read

Author

Josh Elijah

CEO and Head of Hardware

Performance & Benchmarks

Detailed 5V regulator performance analysis for the original SwitchBlox, covering output voltage stability, efficiency under load, and power consumption measurements across operating conditions.

SwitchBlox includes a 5V output that can be used to power downstream devices. To help you integrate it confidently, we ran a series of tests to quantify how that output performs in terms of voltage stability and thermal behaviour under load.

All tests were conducted on SwitchBlox Rev E2. Results are expected to be broadly representative of previous revisions (excluding Rev A).

Test Setup

Ambient temperature: 25°C
Airflow: 0 LPM (no forced cooling)
SwitchBlox operation: 100 Mbps networking active between two ports
Input voltage: 32V

Top view of SwitchBlox Rev E with the 5V 2A output connector highlighted in green

Results

We tested four output current levels, measuring voltage ripple and temperature rise at each point :
0A:

Oscilloscope trace of the SwitchBlox 5V rail at no load: 5.04V mean with 80mV peak-to-peak ripple

Thermal image of the board at 0A output current

Thermal image of SwitchBlox at no load, warmest area reaching 36°C

0.5A:

Oscilloscope trace of the SwitchBlox 5V rail under 0.5A load: 5.04V mean, 80mV peak-to-peak

5V Output at 0.5A load current

AC-coupled oscilloscope capture at 0.5A load showing 162mV peak-to-peak switching spikes

5V Output Ripple (AC Coupled oscilloscope trace) at 0.5A load current

Thermal image of SwitchBlox at 0.5A load, regulator area reaching 48°C

1A:

Oscilloscope trace of the 5V rail at 1A load: 5.04V mean, 320mV peak-to-peak ripple

5V Output at 1A load current

AC-coupled ripple capture at 1A load: 238mV peak-to-peak switching noise

5V Output Ripple (AC Coupled oscilloscope trace) at 1A load current

Thermal image of SwitchBlox at 1A load, regulator hotspot reaching 59°C

Thermal image of the board at 1A output current

2A:

Oscilloscope trace of the 5V rail at 2A load: 5.04V mean, 440mV peak-to-peak ripple

5V Output at 2A load current

AC-coupled ripple capture at 2A load: 306mV peak-to-peak switching noise

5V Output Ripple (AC Coupled oscilloscope trace) at 2A load current

Thermal image of SwitchBlox at 2A load, regulator area reaching 79°C

Thermal image of the board at 2A output current

Input Voltage	Output Current	Voltage Ripple (mV)	Temperature Rise (°C)
30V	0A	30	11
30V	0.5A	162	23
30V	1A	238	34
30V	2A	306	54

Chart of SwitchBlox 5V output performance: voltage ripple and board temperature rise versus output current from 0 to 2A

Both voltage ripple and temperature rise show a near-linear relationship with output current. The two main heat sources are the step-down regulator and the flyback diode, both rated to a maximum junction temperature of 125°C.

What This Means in Practice

At maximum load (2A), the board sees a 54°C temperature rise above ambient. Starting from 25°C, that puts the board at 79°C, well within the component ratings. If your operating environment reaches ambient temperatures around 71°C, active cooling of those two components is recommended to maintain long-term reliability.