HT1621BQ

@@ -0,0 +1,99 @@+# HT1621BQ++**HGSEMI** · LCD Drivers · LQFP-48(7x7)++HT1621BQ from HGSEMI, in a LQFP-48(7x7). Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.++## Pinout++| Pin | Name | Type | Function |+|---|---|---|---|+| 1 | /CS | input | Chip-select input, active low, with internal pull-up. When /CS is high, data/command transfers are inhibited and the serial interface is reset. When /CS is low, the host can transfer data and commands. |+| 2 | /RD | input | READ clock input with internal pull-up. RAM data is shifted out onto DATA on the falling edge of /RD; the host latches the data on the following rising edge. |+| 3 | /WR | input | WRITE clock input with internal pull-up. Data on DATA is latched into the HT1621B on the rising edge of /WR. |+| 4 | DATA | bidirectional | Serial data I/O for addresses, commands, and RAM data, with internal pull-up. Driven by the host during writes/commands and by the HT1621B during reads. |+| 5 | VSS | power_in | Ground reference (0 V). |+| 6 | OSCO | output | Crystal / external clock oscillator output. Connect a 32.768 kHz crystal between OSCI and OSCO, or leave OSCO floating when using the internal 256 kHz RC oscillator or an external clock on OSCI. |+| 7 | OSCI | input | Crystal / external clock input. Connects to a 32.768 kHz crystal (with OSCO) or accepts an external 256 kHz clock; leave floating if the internal RC oscillator is used. |+| 8 | VLCD | power_in | LCD bias-voltage input. Sets the LCD drive amplitude; VLCD must be less than or equal to VDD. |+| 9 | VDD | power_in | Main supply, 2.4 V to 5.2 V. |+| 10 | /IRQ | output | Time base / WDT overflow flag output, N-channel open-drain. Requires an external pull-up to VDD; goes low on overflow after IRQ_EN. |+| 11 | /BZ | output | Complementary buzzer drive output. Provides an anti-phase 2 kHz or 4 kHz square wave (selected by TONE2k/TONE4k, enabled by TONE ON) for driving a piezo buzzer differentially with BZ. |+| 12 | BZ | output | Buzzer drive output. Provides a 2 kHz or 4 kHz square wave (selected by TONE2k/TONE4k, enabled by TONE ON) for driving a piezo buzzer differentially with /BZ. |+| 13 | COM0 | output | LCD common (backplane) driver output 0. |+| 14 | COM1 | output | LCD common (backplane) driver output 1. |+| 15 | COM2 | output | LCD common (backplane) driver output 2. |+| 16 | COM3 | output | LCD common (backplane) driver output 3. |+| 17 | SEG31 | output | LCD segment driver output 31. |+| 18 | SEG30 | output | LCD segment driver output 30. |+| 19 | SEG29 | output | LCD segment driver output 29. |+| 20 | SEG28 | output | LCD segment driver output 28. Datasheet notes that on the 48-pin LQFP the SEG27/SEG28 pin ordering is non-standard; verify against silkscreen before layout. |+| 21 | SEG27 | output | LCD segment driver output 27. Datasheet notes that on the 48-pin LQFP the SEG27/SEG28 pin ordering is non-standard; verify against silkscreen before layout. |+| 22 | SEG26 | output | LCD segment driver output 26. |+| 23 | SEG25 | output | LCD segment driver output 25. |+| 24 | SEG24 | output | LCD segment driver output 24. |+| 25 | SEG23 | output | LCD segment driver output 23. |+| 26 | SEG22 | output | LCD segment driver output 22. |+| 27 | SEG21 | output | LCD segment driver output 21. |+| 28 | SEG20 | output | LCD segment driver output 20. |+| 29 | SEG19 | output | LCD segment driver output 19. |+| 30 | SEG18 | output | LCD segment driver output 18. |+| 31 | SEG17 | output | LCD segment driver output 17. |+| 32 | SEG16 | output | LCD segment driver output 16. |+| 33 | SEG15 | output | LCD segment driver output 15. |+| 34 | SEG14 | output | LCD segment driver output 14. |+| 35 | SEG13 | output | LCD segment driver output 13. |+| 36 | SEG12 | output | LCD segment driver output 12. |+| 37 | SEG11 | output | LCD segment driver output 11. |+| 38 | SEG10 | output | LCD segment driver output 10. |+| 39 | SEG9 | output | LCD segment driver output 9. |+| 40 | SEG8 | output | LCD segment driver output 8. |+| 41 | SEG7 | output | LCD segment driver output 7. |+| 42 | SEG6 | output | LCD segment driver output 6. |+| 43 | SEG5 | output | LCD segment driver output 5. |+| 44 | SEG4 | output | LCD segment driver output 4. |+| 45 | SEG3 | output | LCD segment driver output 3. |+| 46 | SEG2 | output | LCD segment driver output 2. |+| 47 | SEG1 | output | LCD segment driver output 1. |+| 48 | SEG0 | output | LCD segment driver output 0. |++## Key specifications++| Parameter | Value |+|---|---|+| Manufacturer | HGSEMI |+| Package | LQFP-48(7x7) |+| Category | LED-drv |+| Pins | 48 |++## Ordering variants++- `HT1621BQQ`+- `HT1621BQ`+- `HT1621BQDQ`+- `HT1621BQHT1621BDQ`+- `HT1621BQ`+- `HT1621BQM/TR`+- `HT1621BQHT1621B`+- `HT1621BQHT1621BM/TR`+- `HT1621BQMS/TR`+- `HT1621BQHT1621BMS/TR`+- `HT1621BQDM/TR`+- `HT1621BQHT1621BDM/TR`++## CAD (KiCad official)++- Symbol: `HT1621BQ`+- Footprint: `Package_QFP:LQFP-48_7x7mm_P0.5mm`+- 3D model: LQFP-48(7x7) (KiCad packages3D, STEP)++## Provenance++Data extracted from the manufacturer datasheet, not a distributor listing:++- **Datasheet:** [HGSEMI datasheet](docs/ht1621bq-datasheet.pdf) (19 pp, sha256 `38800fa307b08f96`, retrieved 2026-08-17, 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:** `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/ht1621bq-datasheet.pdf)