# DS1307MM

**HGSEMI** · Real Time Clocks · MSOP-8

DS1307MM from HGSEMI, in a MSOP-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 | X1 | passive | 32.768 kHz crystal pin; the datasheet specifies a crystal load capacitance (CL) of 12.5 pF, and when the device is driven by an external 32.768 kHz oscillator, this pin is the oscillator input. |
| 2 | X2 | passive | 32.768 kHz crystal pin; it is left floating when the device is driven by an external 32.768 kHz oscillator on X1. |
| 3 | VBAT | power_in | +3V lithium battery or other battery input that must be held between 2.0 V and 3.5 V for proper operation, and it keeps the RTC and RAM powered when VCC falls below VBAT. |
| 4 | GND | power_in | Ground reference for the device. |
| 5 | SDA | bidirectional | Serial data input/output of the I2C interface; it is an open-drain pin that requires an external pull-up resistor. |
| 6 | SCL | input | Serial clock input of the I2C interface; it is an open-drain pin that requires an external pull-up resistor. |
| 7 | SQW/OUT | output | Square-wave output driver (1 Hz, 4.096 kHz, 8.192 kHz or 32.768 kHz when SQWE=1) or a static output level controlled by the OUT bit when square-wave output is disabled; it is an open-drain pin that requires an external pull-up resistor. |
| 8 | VCC | power_in | Power supply input of +5 V; the datasheet specifies VCC from 4.5 V to 5.5 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HGSEMI |
| Package | MSOP-8 |
| Category | Clock/Timing |
| 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 (recommended) | VCC | 4.5 | 5 | 5.5 | V |  | 3 |
| Logic 1 input voltage | VIH | 2.2 |  |  | V | Max printed as VCC+0.3 | 3 |
| Logic 0 input voltage | VIL | -0.5 |  | 0.8 | V |  | 3 |
| Battery voltage | VBAT | 2 |  | 3.5 | V | Column placement inferred from layout | 3 |
| Input leakage current (SCL) | ILI |  |  | 1 | µA |  | 3 |
| I/O leakage current (SDA and SQW/OUT) | ILO |  |  | 1 | µA |  | 3 |
| Logic 0 output voltage | VOL |  |  | 0.4 | V | IOL=5mA | 3 |
| Operating supply current | ICCA |  |  | 1.5 | mA | note 7: SCL at maximum frequency, 100kHz | 3 |
| Standby current | ICCS |  |  | 200 | µA | note 1: VCC, SDA and SCL = 5.0V | 3 |
| Battery current (OSC ON, SQW/OUT OFF) | IBAT1 |  | 300 | 500 | nA | SQW/OUT OFF; note 2: VCC=0V, VBAT=3V | 3 |
| Battery current (OSC ON, SQW/OUT ON 32kHz) | IBAT2 |  | 480 | 800 | nA | SQW/OUT ON (32kHz) | 3 |
| Power-fail voltage | VPF | 1.216 | 1.25 | 1.284 | V | Printed as 1.216×VBAT / 1.25×VBAT / 1.284×VBAT; note 8: VBAT=3.0V | 3 |
| SCL clock frequency | fSCL | 0 |  | 100 | kHz |  | 4 |
| Bus free time between STOP and START | tBUF | 4.7 |  |  | µs |  | 4 |
| START condition hold time | tHDSTA | 4 |  |  | µs | note 3 | 4 |
| SCL low period | tLOW | 4.7 |  |  | µs |  | 4 |
| SCL high period | tHIGH | 4 |  |  | µs |  | 4 |
| START condition setup time | tSUSTA | 4.7 |  |  | µs |  | 4 |
| Data hold time | tHDDAT | 0 |  |  | µs | notes 4, 5 | 4 |
| Data setup time | tSUDAT | 250 |  |  | ns |  | 4 |
| SDA and SCL rise time | tR |  |  | 1000 | ns |  | 4 |
| SDA and SCL fall time | tF |  |  | 300 | ns |  | 4 |
| STOP condition setup time | tSUSTO | 4.7 |  |  | µs |  | 4 |
| Capacitive load per bus | CB |  |  | 400 | pF | note 6: sum of bus capacitances | 4 |
| I/O capacitance | CI/O |  |  | 10 | pF | TA=25℃ | 4 |
| Specified crystal load capacitance |  |  | 12.5 |  | pF | TA=25℃ | 4 |
| Storage temperature |  | -55 |  | 125 | ℃ |  | 3 |
| Voltage on any pin to GND |  | -0.5 |  | 7 | V |  | 3 |
| Operating temperature (DS1307, non-Z grade) |  | 0 |  | 70 | ℃ | DS1307 commercial grade; DS1307Z (-40 to +85) excluded | 3 |
| Soldering temperature |  |  |  | 260 | ℃ | 10 s | 3 |

## CAD (KiCad official)

- Symbol: `DS1307MM`
- Footprint: `Package_SO:MSOP-8_3x3mm_P0.65mm`
- 3D model: MSOP-8 (KiCad packages3D, STEP)
- 3D model files: `ds1307mm-etched.step` / `ds1307mm-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ds1307mm.step` / `ds1307mm.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HGSEMI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8756372542519160832) (14 pp, sha256 `99d95856b4d3f840`, retrieved 2026-10-18, 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/ds1307mm-datasheet.pdf)