# GX18B20Z

**GXCAS** · Temperature Sensors · SOP-8

GX18B20Z from GXCAS, in a SOP-8. 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 | N.C. | unconnected | Not connected; the datasheet says this pin is an empty pin or one that does not need to be connected. |
| 2 | N.C. | unconnected | Not connected; the datasheet says this pin is an empty pin or one that does not need to be connected. |
| 3 | VDD | power_in | Supply pin for external power, 2.5 V to 5.5 V per the DC characteristics; in parasitic-power mode this pin must be connected to ground. |
| 4 | DQ | bidirectional | 1-Wire data input/output; it requires an external pull-up of about 5 kΩ (4.7 kΩ in the application circuit) and also supplies the chip in parasitic-power mode. |
| 5 | GND | power_in | Ground reference pin for the device; all voltages are referenced to this pin. |
| 6 | N.C. | unconnected | Not connected; the datasheet says this pin is an empty pin or one that does not need to be connected. |
| 7 | N.C. | unconnected | Not connected; the datasheet says this pin is an empty pin or one that does not need to be connected. |
| 8 | N.C. | unconnected | Not connected; the datasheet says this pin is an empty pin or one that does not need to be connected. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | GXCAS |
| Package | SOP-8 |
| Category | Sensors |
| Pins | 8 |

## 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, local supply | VDD | 2.5 |  | 5.5 | V | 局部供电 (local supply); table header -55°C to +100°C | 21 |
| Pull-up supply voltage, parasitic supply | VPU | 2.5 |  | 5.5 | V | 寄生供电 (parasitic supply); notes 1, 2 | 21 |
| Pull-up supply voltage, local supply | VPU | 2.5 |  |  | V | 局部供电 (local supply); max printed as VDD | 21 |
| Input logic low voltage | VIL | -0.3 |  | 0.8 | V |  | 21 |
| Input logic high voltage, local supply | VIH | 2.2 |  |  | V | 局部供电 (local supply); max printed as lower of 5.5 and VDD+0.3 | 21 |
| Input logic high voltage, parasitic supply | VIH | 2.5 |  |  | V | 寄生供电 (parasitic supply) | 21 |
| Sink current | IL | 4 |  |  | mA | VI/O = 0.4V; note 4: logic-0 level obtained at 4 mA sink | 21 |
| Standby current | IDDS |  | 750 | 1000 | nA | note 7: defined at 70°C; note 8: DQ at GND to GND+0.3V or VDD-0.3V to VDD | 21 |
| Operating current | IDD |  | 1 | 1.5 | mA | VDD = 5V; note 9: during temperature conversion and EEPROM write | 21 |
| DQ input current | IDQ |  |  | 5 | μA | note 10: DQ high (high-impedance state) | 21 |
| Drift |  | -0.2 |  | 0.2 | ℃ | note 11: +125°C, VDD = 5.5V, 1000 hours | 21 |
| Temperature error | tERR | -0.4 |  | 0.4 | ℃ | -10℃~+85℃ | 21 |
| Temperature error | tERR | -1.2 |  | 1.2 | ℃ | -55℃~+125℃ | 21 |
| Accuracy, SOP8 package (product list) |  | -0.5 |  | 0.5 | ℃ |  | 25 |
| Voltage range on each pin to ground |  | -0.5 |  | 6 | V |  | 21 |
| Operating temperature range |  | -55 |  | 125 | ℃ |  | 21 |
| Storage temperature range |  | -55 |  | 125 | ℃ |  | 21 |
| NV write cycle time | tWR | 8 |  | 12 | ms |  | 22 |
| EEPROM writes | NEEWR | 1000 |  |  | writes | -55°C to +55°C | 22 |
| EEPROM data retention | tEEDR | 10 |  |  | years | -55°C to +55°C | 22 |
| Temperature conversion time | tCONV |  |  | 50 | ms | 9-bit resolution | 22 |
| Temperature conversion time | tCONV |  |  | 100 | ms | 10-bit resolution | 22 |
| Temperature conversion time | tCONV |  |  | 200 | ms | 11-bit resolution | 22 |
| Temperature conversion time | tCONV |  |  | 400 | ms | 12-bit resolution | 22 |
| Time to strong pullup on | tSPON |  |  | 10 | µs | Start Convert T command issued | 22 |
| Time slot | tSLOT | 60 |  | 120 | µs |  | 22 |
| Recovery time | tREC | 1 |  |  | µs |  | 22 |
| Write 0 low time | tLOW0 | 60 |  | 120 | µs |  | 22 |
| Write 1 low time | tLOW1 | 1 |  | 15 | µs |  | 22 |
| Read data valid | tRDV |  |  | 15 | µs |  | 22 |
| Reset time high | tRSTH | 480 |  |  | µs |  | 22 |
| Reset time low | tRSTL | 1 |  |  | ms |  | 22 |
| Presence-detect high | tPDHIGH | 15 |  | 60 | µs |  | 22 |
| Presence-detect low | tPDLOW | 60 |  | 240 | µs |  | 22 |
| Capacitance, CIN/OUT | CIN/OUT |  |  | 25 | pF |  | 22 |

## CAD (KiCad official)

- Symbol: `GX18B20Z`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOP-8 (KiCad packages3D, STEP)
- 3D model files: `gx18b20z-etched.step` / `gx18b20z-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `gx18b20z.step` / `gx18b20z.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [GXCAS datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588907354239225857) (27 pp, sha256 `e85c345c5677d199`, retrieved 2026-10-19, 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/gx18b20z-datasheet.pdf)