XC121S101

Si Change · Analog To Digital Converters (ADC) · SOT-23-6

XC121S101 from Si Change, in a SOT-23-6. 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	VA	power_in	Positive analog supply input (4 V to 5.25 V single supply), which also serves as the ADC reference voltage; the VA supply should be set greater than or equal to the maximum VIN input signal to avoid saturating the maximum conversion code.
2	GND	power_in	Analog input signal ground; all analog and digital signals are referenced to this pin.
3	VIN	power_in	Analog signal input, single-ended unipolar, with a signal range of 0 V to VA.
4	SCLK	input	Serial clock input that directly controls the conversion and readout process; the 16th falling edge ends the conversion cycle.
5	SDATA	output	Serial data output; data is output MSB first after three leading zeros, and the pin goes tri-state after the 16th falling SCLK edge.
6	CS	input	Active-low chip select; a falling edge on CS wakes the device and starts a conversion, and CS must be held high for at least 1 µs after SDATA enters tri-state before the next conversion.

Key specifications

Parameter	Value
Manufacturer	Si Change
Package	SOT-23-6
Category	Data Acquisition
Pins	6

Electrical characteristics

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

Parameter	Symbol	Min	Max	Unit	Page
Supply voltage (VA), single supply	VA	4	5.25	V	1
Integral nonlinearity (INL)	INL	-1.25	1.25	LSB	2
Differential nonlinearity (DNL)	DNL	-1	1	LSB	2
Operating temperature range		-40	85	°C	1

CAD (KiCad official)

Symbol: XC121S101
Footprint: Package_TO_SOT_SMD:SOT-23-6
3D model: SOT-23-6 (KiCad packages3D, STEP)
3D model files: xc121s101-etched.step / xc121s101-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); xc121s101.step / xc121s101.glb are the bare package body.

Provenance

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

Datasheet: Si Change datasheet (4 pp, sha256 dcc7880856c2f232, retrieved 2026-10-14, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), 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

# XC121S101

**Si Change** · Analog To Digital Converters (ADC) · SOT-23-6

XC121S101 from Si Change, in a SOT-23-6. 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 | VA | power_in | Positive analog supply input (4 V to 5.25 V single supply), which also serves as the ADC reference voltage; the VA supply should be set greater than or equal to the maximum VIN input signal to avoid saturating the maximum conversion code. |
| 2 | GND | power_in | Analog input signal ground; all analog and digital signals are referenced to this pin. |
| 3 | VIN | power_in | Analog signal input, single-ended unipolar, with a signal range of 0 V to VA. |
| 4 | SCLK | input | Serial clock input that directly controls the conversion and readout process; the 16th falling edge ends the conversion cycle. |
| 5 | SDATA | output | Serial data output; data is output MSB first after three leading zeros, and the pin goes tri-state after the 16th falling SCLK edge. |
| 6 | CS | input | Active-low chip select; a falling edge on CS wakes the device and starts a conversion, and CS must be held high for at least 1 µs after SDATA enters tri-state before the next conversion. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Si Change |
| Package | SOT-23-6 |
| Category | Data Acquisition |
| Pins | 6 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Supply voltage (VA), single supply | VA | 4 |  | 5.25 | V |  | 1 |
| Integral nonlinearity (INL) | INL | -1.25 |  | 1.25 | LSB |  | 2 |
| Differential nonlinearity (DNL) | DNL | -1 |  | 1 | LSB |  | 2 |
| Operating temperature range |  | -40 |  | 85 | °C |  | 1 |

## CAD (KiCad official)

- Symbol: `XC121S101`
- Footprint: `Package_TO_SOT_SMD:SOT-23-6`
- 3D model: SOT-23-6 (KiCad packages3D, STEP)
- 3D model files: `xc121s101-etched.step` / `xc121s101-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `xc121s101.step` / `xc121s101.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Si Change datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603387431764967424) (4 pp, sha256 `dcc7880856c2f232`, retrieved 2026-10-14, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), 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/xc121s101-datasheet.pdf)