lm120/lm320 series 3-terminal negative regulators
The LM120/LM320 series are three‑terminal negative regulators offering fixed output voltages of –5 V, –12 V, and –15 V with up to 1.5 A load current. They require only a single external compensation capacitor, providing simple implementation and reliable performance.
The devices include internal current limiting and thermal shutdown for overload protection, and can be programmed to higher output voltages using a resistive divider. Various TO‑3, TO‑39, and TO‑220 packages are available, each with specific power dissipation ratings.
| Fixed output voltages | -5 V, -12 V, -15 V |
|---|---|
| Maximum load current | 1.5 A |
| Input‑output voltage differential | 30 V |
| Package TO‑3 power dissipation | 20 W, 1.5 A |
| Package TO‑39 power dissipation | 0.5 W, 0.5 A |
| Package TO‑220 power dissipation | 15 W, 1.5 A |
| Ripple rejection (120 Hz) | 54‑64 dB |
| Thermal resistance, junction‑to‑case | 3 °C/W |
| Thermal resistance, junction‑to‑ambient | 35 °C/W |
The LM120 series provides fixed output voltages of –5 V, –12 V, and –15 V.
Only one external compensation capacitor at the output is required.
The maximum input‑output voltage differential is 30 V.