Hello David Murray,
Thank you for writing in.
Here are two recommendations to you:
#090398
DROK® LM2587 Auto Step Up Down Converter 24W 2A Boost Buck Module DC 3-35V to 1.2-30V Solar Energy Power Supply Charging Board Battery Voltage Regulator
Feature:
Module Properties: non-isolated buck-boost module
Input voltage: DC 3-35V
Output voltage: DC 1.25-30V (adjustable)
Output Current: 2A (when 9-35V input and 12V output, if 5V output can achieve 3A)
Input Current: 3.5A (MAX)
Output power: natural cooling 18W (input voltage greater than 10V), if install heat sink can achieve 24W
Output ripple: 20M bandwidth (for reference)
Input 10-14V, output 12V 0.2A, ripple 50mV
Operating Temperature: Industrial (-40°c to +85°c) (if ambient temperature exceeds 40 degrees, lower power use, or to enhance heat dissipation)
Full load temperature rise: 45°c
No-load current: Typical 10mA (10-14V switch 12V)
Load regulation: +/-1%
Voltage regulation: +/-0.5%
Dynamic response speed: 5% 200uS
Short circuit protection: Yes (10 seconds)
Input Reverse Polarity Protection: None (Please Series diode at the input port.)
Installation: can screw (diameter 3 mm), 2 fixing holes
Connection: Welding, can be directly soldered to a PCB

Applications:
Battery voltage regulator, 12V battery (10-14V) can output voltage at 12V, 24V battery output voltage at 24V.
Solar charging regulator, it can stabilize voltage fluctuations in solar cells, and can give the battery charge, battery to avoid overshoot.
In order to power your electronic devices, designed for wide voltage range.

#090638
DROK® DC-DC Buck Boost Converter 5V-25V to 0.5-25V 2A High Efficiency Voltage Regulator 5V 12V Variable Volt Power Supply Stabilizers with Green LED Voltmeter for Car Battery Fan
Product parameters:
Input voltage: DC 5.0-25V
Output voltage: DC 0.5V-25V (adjustable)
Continuous Output Current: 2A (max)
Continuous Input Current: 2A (max)
Input / Output Power: 25W (max)
Display color: green
Dimensions: 47 * 41 * 16mm (L * W * H)

Features:
Input and output voltage can display alternately
The starting state can be set freely.
On the right side is a momentary switch that is for turning the output on and off, you don’t have to disconnect it to turn off whatever you have connected, it is more convenient to control the output.
This module have the big power MOS to protect the circuit in case of connecting reversely, which can improve the efficiency and reliability.

Working Mode:
Input voltage mode: default display input voltage, display as “.”, LED indicator ON, the output is off.
Output voltage mode: Press S1 switch to output voltage mode, display “.”, LED indicator off, if turn off the output, display “OFF”.
Alternate mode: Press S1 key again, display input/output voltage alternately in 3 seconds, press S1 again switch to “input voltage mode”.

Memory Mode:
Long press S1key for 3 seconds, the module automatically remembers the current work status as the default power-on state.
[0]means boot default display input voltage
[1]means boot default display output voltage
[2]means boot default display input/output voltage alternately

Hope this can help you.
Best regards

Hello David Murray,
You’re welcome.
If there is any questions, please feel free to contact us.
Have a nice day!
Best regards