# ZLDO1117QK50TC

**Diodes Incorporated** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-252

ZLDO1117QK50TC from Diodes Incorporated, in a TO-252. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | GND | power_in | Ground reference pin for the fixed-output ZLDO1117Q-50 variant. On adjustable variants this same pin is the ADJ feedback node; on this 5.0V fixed-mode part it is tied internally to the reference divider and must be connected to system ground. |
| 2 | VOUT | power_out | Regulated 5.0V output of the LDO, capable of sourcing up to 1A. Requires a minimum 4.7µF capacitor to ground (0.05Ω ≤ ESR ≤ 0.5Ω) for stability; a larger output capacitor improves AC load response. The exposed tab is also VOUT. |
| 3 | VIN | power_in | Input supply pin, 2.7V to 18V. A large storage capacitor (0.05Ω ≤ ESR ≤ 0.5Ω) should be placed close to this pin so the input does not sag below the minimum dropout during load transients. VIN must be at least ~1.3V above VOUT for proper regulation (6.3V minimum for 5.0V output at full load). |
| TAB | VOUT | power_out | Exposed thermal tab electrically tied to VOUT. Solder to the PCB copper pour associated with the output net to conduct heat and improve power dissipation (θJA = 73 °C/W, θJC = 12 °C/W for TO252). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Diodes Incorporated |
| Package | TO-252 |
| Category | PMIC |
| Pins | 4 |

## Ordering variants

Same part, different packaging or reel option.

- `ZLDO1117QK50TC`
- `ZLDO1117QG50TA`

## CAD (KiCad official)

- Symbol: `ZLDO1117QK50TC`
- Footprint: `Package_TO_SOT_SMD:TO-252-2`
- 3D model: TO-252 (KiCad packages3D, STEP)
- 3D model files: `zldo1117qk50tc-etched.step` / `zldo1117qk50tc-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `zldo1117qk50tc.step` / `zldo1117qk50tc.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Diodes Incorporated datasheet](docs/zldo1117qk50tc-datasheet.pdf) (14 pp, sha256 `52a05840bdb17cd6`, retrieved 2026-08-17, tier: lcsc)
- **Extractor:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/zldo1117qk50tc-datasheet.pdf)