# KSA1220A

**Changjing** · Bipolar Transistors - BJT · TO-126

KSA1220A from Changjing, in a TO-126. 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 | EMITTER | passive | Emitter terminal of the KSA1220A PNP transistor in the TO-126 package, listed as pin 1 in the datasheet pinout. |
| 2 | COLLECTOR | passive | Collector terminal of the KSA1220A PNP transistor, with collector-emitter voltage rated at -160 V and DC collector current at -1.2 A. |
| 3 | BASE | passive | Base terminal of the KSA1220A PNP transistor, with base current rated at -0.3 A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | TO-126 |
| Category | Triode/MOS Tube/Transistor |
| Pins | 3 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Collector-Base Voltage | VCBO |  |  | -160 | V | KSA1220A | 1 |
| Collector-Emitter Voltage | VCEO |  |  | -160 | V | KSA1220A | 1 |
| Emitter-Base Voltage | VEBO |  |  | -5 | V |  | 1 |
| Collector Current (DC) | IC |  |  | -1.2 | A |  | 1 |
| Collector Current (pulse) | ICP |  |  | -2.5 | A | PW ≤10ms,Duty Cycle ≤2 % | 1 |
| Base Current | IB |  |  | -0.3 | A |  | 1 |
| Collector Power Dissipation | PC |  |  | 1.25 | W | Ta = 25 ℃ | 1 |
| Collector Power Dissipation | PC |  |  | 20 | W | Tc = 25 ℃ | 1 |
| Operation Junction and Storage Temperature Range | TJ,Tstg | -55 |  | 150 | ℃ |  | 1 |
| Collector cut-off current | ICBO |  |  | -1 | μA | VCB=-120V, IE=0 | 2 |
| Emitter cut-off current | IEBO |  |  | -1 | μA | VEB=-3 V, IC=0 | 2 |
| DC current gain | hFE(1) | 35 |  |  |  | VCE=-5V, IC=-5mA | 2 |
| DC current gain | hFE(2) | 60 |  | 320 |  | VCE=-5V, IC=-300mA | 2 |
| Collector-emitter saturation voltage | VCE(sat) |  | -0.4 | -0.7 | V | IC=-1 A, IB=-200mA (1) | 2 |
| Base-emitter saturation voltage | VBE(sat) |  | -1 | -1.3 | V | IC=-1 A, IB=-200mA (1) | 2 |
| Transition frequency | fT |  | 175 |  | MHz | VCE=-5V, IC=-200mA | 2 |
| Collector output capacitance | Cob |  | 26 |  | pF | VCB=-10V, IE=0, f=1MHz | 2 |

## CAD (KiCad official)

- Symbol: `KSA1220A`
- Footprint: `Package_TO_SOT_THT:TO-126-3_Vertical`
- 3D model: TO-126 (KiCad packages3D, STEP)
- 3D model files: `ksa1220a-etched.step` / `ksa1220a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ksa1220a.step` / `ksa1220a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](docs/ksa1220a-datasheet.pdf) (3 pp, sha256 `1f9e824f10ee6b53`, retrieved 2026-10-27, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `off` (skipped (clean text read)), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/ksa1220a-datasheet.pdf)