QRP Power Supply: 12.0V / 9.0V VLDO Linear Regulator (M9OMS VLDO V2)

**OUT OF STOCK - NEW STOCK ARRIVING WC 20/07**


M9OMS VLDO V2 — Very Low Dropout Linear Regulator Kit

This discrete LDO kit delivers 2 A continuous with a very low dropout.

For a nylon 3D printed enclosure, please see my other listing 267715531314. To print your own, search "M9OMS" on Thingiverse.

Electrical Specification
Parameter Value Note
Input voltage8–18 V DC
Output voltage9.0 / 12.0 / 13.8 VSet via header pins, trim via R7
Max output current2 AContinuous
Dropout voltage<100 mVAt 1 A
Quiescent current~6 mAVin = 13 V
Load regulation~20 mV / ~40 mV0.1 A to 1 A  /  0.1 A to 2 A
Transient response~25-40 µs recovery
0.1 A  1.5 A

A no-load offset of 20-30mV is exhibited, resolving at currents above 30 mA. Adding a pre-load resistor is recommended for applications requiring tight regulation accuracy at very light loads.

Dropout Operation
The VLDO V2 ensures uninterrupted power as the source voltage declines. Once regulation threshold is reached, the device enters a dropout state. In this mode, the output tracks the input with a very low overhead, allowing downstream equipment to remain operational across the battery discharge curve.
Load Regulation (12 V setting) M9OMS VLDO V2 — regulation across load levels 8.0 9.0 10.0 11.0 12.0 9 10 11 12 13 14 15 16 DROPOUT REGULATION Vout = Vin Load 0 mA 100 mA 500 mA 1000 mA 1500 mA 2000 mA Input Voltage Vin (V) Output Voltage Vout (V)
What's in the BOX

Input and output through-hole pads accommodate up to 18 AWG stranded wire.

Thermal Note

Power dissipated in the pass element is:

P = (Vin − Vout) × Iload

The supplied heatsink is rated for 1.5 W continuous, or 3 W at 50% duty cycle (typical for SSB/CW radio operation). At a 13.8 V input and 12 V / 1 A output, dissipation is 1.8 W - typical intermittent operation will not require external cooling. For higher input voltages, increased current, or continuous-duty operation at maximum load, external cooling is required. Bottom-mount the PMOS to couple the pass element directly to a metal enclosure or a larger external heatsink.

The PCB includes a clearance hole to facilitate bottom-mounting. Always use high-quality thermal paste for optimal heat transfer.

How it Compares
Regulation Knee — V2 vs. V1.1 (12 V setting) Tighter grouping of a board’s traces = less drop 10.5 11.0 11.5 12.0 11 12 13 14 Vout = Vin Board V2 V1.1 Load 100 mA 1 A 2 A Input Voltage Vin (V) Output Voltage Vout (V)