GN1668T from GN Semic, in a SSOP-24-150mil. 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	DIO	bidirectional	Serial data I/O for the 3-wire interface. N-channel open-drain output with internal pull-up resistor; external pull-up not required for typical operation.
2	CLK	input	Serial clock input for the 3-wire interface. Data on DIO is latched on the clock edges; PWCLK min 400 ns, Fmax = 1 MHz at 50% duty.
3	STB	input	Strobe / chip-select input. A high-to-low edge on STB begins a new instruction/data frame on DIO; taking STB high aborts the current transfer.
4	K1	input	Keyboard-matrix return line 1. Internal pull-down resistor (typ. 10 kΩ); asserted high by the SEG/KS scan driver when a key on the K1 row is pressed.
5	K2	input	Keyboard-matrix return line 2. Internal pull-down resistor (typ. 10 kΩ); asserted high by the SEG/KS scan driver when a key on the K2 row is pressed.
6	VDD	power_in	Positive supply input. Recommended operating range 3.0 V to 5.5 V (typ. 5 V); absolute max +7 V. Typical quiescent IDD = 130 µA (no load).
7	SEG1/KS1	output	Multiplexed segment-drive / key-scan output 1. P-channel open-drain sink to VDD; -50 mA max source per SEG. Drives display segments in display cycles and asserts the K1/K2 row during keyboard scan.
8	SEG2/KS2	output	Multiplexed segment-drive / key-scan output 2. P-channel open-drain, -50 mA max.
9	SEG3/KS3	output	Multiplexed segment-drive / key-scan output 3. P-channel open-drain, -50 mA max.
10	SEG4/KS4	output	Multiplexed segment-drive / key-scan output 4. P-channel open-drain, -50 mA max.
11	SEG5/KS5	output	Multiplexed segment-drive / key-scan output 5. P-channel open-drain, -50 mA max.
12	SEG6/KS6	output	Multiplexed segment-drive / key-scan output 6. P-channel open-drain, -50 mA max.
13	SEG7/KS7	output	Multiplexed segment-drive / key-scan output 7. P-channel open-drain, -50 mA max.
14	SEG8/KS8	output	Multiplexed segment-drive / key-scan output 8. P-channel open-drain, -50 mA max.
15	SEG9/KS9	output	Multiplexed segment-drive / key-scan output 9. P-channel open-drain, -50 mA max.
16	SEG10/KS10	output	Multiplexed segment-drive / key-scan output 10. P-channel open-drain, -50 mA max.
17	SEG12/GRID7	output	Multiplexed segment / grid (digit) output. Push-pull P/N-channel open-drain output - acts as SEG12 in 13-segment/4-grid mode, or as GRID7 in 10-segment/7-grid mode.
18	SEG13/GRID6	output	Multiplexed segment / grid output. Push-pull P/N-channel open-drain output; SEG13 in 13-seg/4-grid mode, GRID6 in 11-seg/6-grid mode.
19	SEG14/GRID5	output	Multiplexed segment / grid output. Push-pull P/N-channel open-drain output; SEG14 in 13-seg/4-grid mode, GRID5 in 12-seg/5-grid mode.
20	GRID4	output	Grid (digit common) output 4. N-channel open-drain output; +150 mA max sink, VOL = 0.3 V at 100 mA typ. Drives one common-cathode digit.
21	GRID3	output	Grid (digit common) output 3. N-channel open-drain output; +150 mA max sink.
22	GND	power_in	Ground / reference (0 V). Common return for supply and all outputs.
23	GRID2	output	Grid (digit common) output 2. N-channel open-drain output; +150 mA max sink.
24	GRID1	output	Grid (digit common) output 1. N-channel open-drain output; +150 mA max sink.

Key specifications

Parameter	Value
Manufacturer	GN Semic
Package	SSOP-24-150mil
Category	LED-drv
Pins	24

Ordering variants

Same part, different packaging or reel option.

GN1668TT
GN1668T

CAD (KiCad official)

Symbol: GN1668T
Footprint: Package_SO:SSOP-24_5.3x8.2mm_P0.65mm
3D model: SSOP-24-150mil (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`gn1668t.step`	315 KB	You want the bare part, or you mark your own boards.
`gn1668t-etched.step`	2.5 MB	You want the part with `GN1668T` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 630 faces against 387 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: GN Semic datasheet (16 pp, sha256 23e60bbc70cfe4a2, 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