Manufacturer: Texas Instruments, STMicroelectronics, onsemi
Figures from the datasheet: Texas Instruments SNOSBT0L, rev. L, September 2016
5 V, 1.5 A fixed positive linear voltage regulator with internal current limiting and thermal shutdown, in TO-220 and D2PAK packages.
The LM7805 is a three-terminal positive regulator with a fixed 5 V output, intended for local on-card regulation. Internal current limiting, thermal shutdown and safe-area protection make it hard to damage; with adequate heatsinking it delivers up to 1.5 A (2.1 A typical short-circuit current). It needs at least 7.5 V at the input to stay in regulation (about 2 V of dropout at 1 A) and accepts up to 35 V. The figures on this page come from the Texas Instruments LM340/LM7805 datasheet (SNOSBT0L), cross-checked with onsemi MC7800/D; 7805 regulators from STMicroelectronics, onsemi and other vendors share the pinout, but their limits and thermal figures differ slightly, so check the datasheet of the part you use.
Interactive package pinout and pin mapping for TO-220-3.
Package illustration, not a dimensioned mechanical drawing.
| # | Pin name | Type | 5V Tolerant | Alternate functions / details |
|---|---|---|---|---|
| IN | power in | — | Unregulated DC input (at least 7.5 V for regulation, 35 V absolute maximum) | |
| GND | ground | — | Common ground (electrically connected to the TO-220 metal tab) | |
| OUT | power out | — | Regulated +5 V output (up to 1.5 A with adequate heatsinking) |
| Parameter | Min | Typical | Max | Unit | Test condition |
|---|---|---|---|---|---|
| Output Voltage(VOUT) | 4.8 | 5 | 5.2 | V | TJ = 25 °C, 5 mA ≤ IO ≤ 1 A, VI = 10 V |
| Output Voltage (line, load, temperature)(VOUT_FULL) | 4.75 | 5 | 5.25 | V | PD ≤ 15 W, 5 mA ≤ IO ≤ 1 A, 7.5 V ≤ VIN ≤ 20 V, 0–125 °C |
| Input Voltage Required for Regulation(VIN_MIN) | 7.5 | — | — | V | TJ = 25 °C, IO ≤ 1 A |
| Dropout Voltage(VDROP) | — | 2 | — | V | TJ = 25 °C, IO = 1 A (no maximum specified) |
| Output Current(IOUT) | — | 1.5 | — | A | With adequate heatsinking |
| Short-Circuit Current(ISC) | — | 2.1 | — | A | TJ = 25 °C |
| Peak Output Current(IPK) | — | 2.4 | — | A | TJ = 25 °C |
| Quiescent Current(IQ) | — | — | 8 | mA | TJ = 25 °C, IO ≤ 1 A (8.5 mA max over temperature) |
| Line Regulation(RegLine) | — | 3 | 50 | mV | TJ = 25 °C, IO = 500 mA, 7 V ≤ VIN ≤ 25 V |
| Load Regulation(RegLoad) | — | 10 | 50 | mV | TJ = 25 °C, 5 mA ≤ IO ≤ 1.5 A |
| Ripple Rejection(RR) | 62 | 80 | — | dB | f = 120 Hz, 8 V ≤ VIN ≤ 18 V, TJ = 25 °C, IO ≤ 1 A |
| Max input voltage | 35 V |
| Operating junction temperature | 0 – 125 °C |
| Storage temperature | -65 – 150 °C |
| ESD rating (HBM) | 2000 V |
| Thermal resistance θJA (TO-220) | 54 °C/W |
| Thermal resistance θJC (TO-220) | 4 °C/W |
| Thermal resistance θJA (D2PAK) | 50 °C/W |
| Thermal resistance θJC (D2PAK) | 1.5 °C/W |
Each column comes from that manufacturer's own datasheet. Highlighted values differ from the reference part; "not checked" means we have not compared that value yet.
| Parameter | LM7805Texas Instruments · reference | MC7805CTonsemi |
|---|---|---|
| Output Voltage (VOUT) | 4.8 / 5 / 5.2 V | 4.8 / 5 / 5.2 V |
| Output Voltage (line, load, temperature) (VOUT_FULL) | 4.75 / 5 / 5.25 V | 4.75 / 5 / 5.25 VSpecified for 7.0 V ≤ VIN ≤ 20 V |
| Dropout Voltage (VDROP) | 2 V | 2 V |
| Output Current (IOUT) | 1.5 A | 1 A(differs from the reference part)Rated for output current in excess of 1.0 A |
| Peak Output Current (IPK) | 2.4 A | 2.2 A(differs from the reference part) |
| Quiescent Current (IQ) | ≤ 8 mA | 3.2 mA (≤ 6.5)(differs from the reference part) |
| Load Regulation (RegLoad) | 10 mV (≤ 50) | 1.3 mV (≤ 25)(differs from the reference part) |
| Ripple Rejection (RR) | 80 dB (≥ 62) | 83 dB (≥ 62)(differs from the reference part) |
| Max input voltage | ≤ 35 V | ≤ 35 V |
| Storage temperature | -65 / 150 °C | -65 / 150 °C |
| θJA (TO-220) | 54 °C/W | 65 °C/W(differs from the reference part) |
| θJC (TO-220) | 4 °C/W | 5 °C/W(differs from the reference part) |
| θJC (D2PAK) | 1.5 °C/W | 5 °C/W(differs from the reference part) |
Real-world hardware caveats, PCB layout constraints and silicon errata to know before manufacturing.
A linear regulator turns all excess voltage into heat: PD = (VIN − 5 V) × IO, and the junction reaches TJ = TA + PD × θJA. A 500 mA load from 12 V dissipates 3.5 W; in free air the TO-220 (θJA 54 °C/W) would rise about 189 °C, so the regulator goes into thermal shutdown.
TI specifies 7.5 V as the input needed to maintain line regulation (dropout is about 2 V at 1 A). When the input sags below that — a discharged 9 V battery or ripple troughs of a loaded transformer supply — ripple passes through to the 5 V rail.
TI: the input capacitor (0.22 µF) is required only if the regulator is far from the supply filter (more than about 6 in / 150 mm); the output capacitor is not needed for stability but a 0.1 µF ceramic improves transient response. onsemi warns that output capacitors below 0.1 µF can cause instability.
If the input is shorted to ground while a large output capacitor is charged, the capacitor discharges backwards through the regulator and can destroy it. TI: generally no protection diode is needed for output capacitance up to 10 µF.
If only the ground pin is disconnected, the output rises towards the unregulated input voltage and can damage the circuits on the 5 V rail; reconnecting ground with power on can damage the regulator. This typically happens when plugging modules into a powered socket.
| Part number (MPN) | Manufacturer | Compatibility | Electrical differences / BOM considerations |
|---|---|---|---|
| L7805CV | STMicroelectronics | pin to pin drop in | Same TO-220 pinout (IN, GND, OUT); check the ST L78 datasheet for its exact limits. |
| MC7805CT | onsemi | pin to pin drop in | Same TO-220 pinout; onsemi rates the MC7800 series for output current in excess of 1.0 A and gives θJA 65 °C/W for TO-220. |
| TSR 1-2450 | Traco Power | differing electrical limits | Switching regulator module in a TO-220-compatible footprint; check input range, output current and output noise in the Traco datasheet. |
Primary semiconductor vendor datasheets, errata, and application notes.
Found a pin, package or parameter that does not match the datasheet? Report it.
Opens a public form on GitHub with this page already filled in; a free GitHub account is needed. How reports and confirmations work