# TLP521-4

**TOSHIBA** · Transistor, Photovoltaic Output Optoisolators · DIP-16

TLP521-4 from TOSHIBA, in a DIP-16. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | ANODE1 | input | LED anode of channel 1; forward current max 50 mA (recommended 16 mA typ, 25 mA max), reverse voltage 5 V max. |
| 2 | CATHODE1 | passive | LED cathode of channel 1. |
| 3 | ANODE2 | input | LED anode of channel 2; forward current max 50 mA (recommended 16 mA typ, 25 mA max), reverse voltage 5 V max. |
| 4 | CATHODE2 | passive | LED cathode of channel 2. |
| 5 | ANODE3 | input | LED anode of channel 3; forward current max 50 mA (recommended 16 mA typ, 25 mA max), reverse voltage 5 V max. |
| 6 | CATHODE3 | passive | LED cathode of channel 3. |
| 7 | ANODE4 | input | LED anode of channel 4; forward current max 50 mA (recommended 16 mA typ, 25 mA max), reverse voltage 5 V max. |
| 8 | CATHODE4 | passive | LED cathode of channel 4. |
| 9 | EMITTER4 | passive | Phototransistor emitter of channel 4; emitter-collector voltage 7 V max. |
| 10 | COLLECTOR4 | passive | Phototransistor collector of channel 4; VCEO 55 V max, collector current 50 mA max. |
| 11 | EMITTER3 | passive | Phototransistor emitter of channel 3; emitter-collector voltage 7 V max. |
| 12 | COLLECTOR3 | passive | Phototransistor collector of channel 3; VCEO 55 V max, collector current 50 mA max. |
| 13 | EMITTER2 | passive | Phototransistor emitter of channel 2; emitter-collector voltage 7 V max. |
| 14 | COLLECTOR2 | passive | Phototransistor collector of channel 2; VCEO 55 V max, collector current 50 mA max. |
| 15 | EMITTER1 | passive | Phototransistor emitter of channel 1; emitter-collector voltage 7 V max. |
| 16 | COLLECTOR1 | passive | Phototransistor collector of channel 1; VCEO 55 V max, collector current 50 mA max. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | TOSHIBA |
| Package | DIP-16 |
| Category | Optoisolators |
| Pins | 16 |

## CAD (KiCad official)

- Symbol: `TLP521-4`
- Footprint: `Package_DIP:DIP-16_W7.62mm`
- 3D model: DIP-16 (KiCad packages3D, STEP)
- 3D model files: `tlp521-4-etched.step` / `tlp521-4-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `tlp521-4.step` / `tlp521-4.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [TOSHIBA datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589839353334960128) (9 pp, sha256 `525c043d61ed3677`, retrieved 2026-10-21, 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/tlp521-4-datasheet.pdf)