SN74LV244APWR from Texas Instruments, in a TSSOP-20. 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	1OE	input	Active-low output-enable for buffer group 1 (1Y1-1Y4). When low, the 1Y outputs are enabled; when high, the 1Y outputs are placed in the high-impedance (3-state) mode.
2	1A1	input	Buffer group 1 data input channel 1. Standard CMOS input; drives corresponding 1Y1 output when 1OE is low.
3	2Y4	tri_state	Buffer group 2 output channel 4. 3-state output driven from 2A4 when 2OE is low; high-impedance when 2OE is high. Drive capability up to 16 mA at VCC = 4.5 V.
4	1A2	input	Buffer group 1 data input channel 2. Standard CMOS input; drives corresponding 1Y2 output when 1OE is low.
5	2Y3	tri_state	Buffer group 2 output channel 3. 3-state output driven from 2A3 when 2OE is low; high-impedance when 2OE is high.
6	1A3	input	Buffer group 1 data input channel 3. Standard CMOS input; drives corresponding 1Y3 output when 1OE is low.
7	2Y2	tri_state	Buffer group 2 output channel 2. 3-state output driven from 2A2 when 2OE is low; high-impedance when 2OE is high.
8	1A4	input	Buffer group 1 data input channel 4. Standard CMOS input; drives corresponding 1Y4 output when 1OE is low.
9	2Y1	tri_state	Buffer group 2 output channel 1. 3-state output driven from 2A1 when 2OE is low; high-impedance when 2OE is high.
10	GND	power_in	Ground reference for the device. Connect to system ground with a low-impedance return path.
11	2A1	input	Buffer group 2 data input channel 1. Standard CMOS input; drives corresponding 2Y1 output when 2OE is low.
12	1Y4	tri_state	Buffer group 1 output channel 4. 3-state output driven from 1A4 when 1OE is low; high-impedance when 1OE is high.
13	2A2	input	Buffer group 2 data input channel 2. Standard CMOS input; drives corresponding 2Y2 output when 2OE is low.
14	1Y3	tri_state	Buffer group 1 output channel 3. 3-state output driven from 1A3 when 1OE is low; high-impedance when 1OE is high.
15	2A3	input	Buffer group 2 data input channel 3. Standard CMOS input; drives corresponding 2Y3 output when 2OE is low.
16	1Y2	tri_state	Buffer group 1 output channel 2. 3-state output driven from 1A2 when 1OE is low; high-impedance when 1OE is high.
17	2A4	input	Buffer group 2 data input channel 4. Standard CMOS input; drives corresponding 2Y4 output when 2OE is low.
18	1Y1	tri_state	Buffer group 1 output channel 1. 3-state output driven from 1A1 when 1OE is low; high-impedance when 1OE is high.
19	2OE	input	Active-low output-enable for buffer group 2 (2Y1-2Y4). When low, the 2Y outputs are enabled; when high, the 2Y outputs are placed in the high-impedance (3-state) mode.
20	VCC	power_in	Positive supply voltage, 2 V to 5.5 V operating range. Decouple locally with a 0.1 uF ceramic capacitor to GND.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	TSSOP-20
Category	Logic
Pins	20

Ordering variants

Same part, different packaging or reel option.

SN74LV244APWR
SN74LV244APWRDB
SN74LV244APWRDBR
SN74LV244APWRDGV
SN74LV244APWRDGVR
SN74LV244APWRDW
SN74LV244APWRDWR
SN74LV244APWRNS
SN74LV244APWRNSR
SN74LV244APWRRGY
SN74LV244APWRRGYR
SN74LV244APWRRKS
SN74LV244APWRRKSR
SN74LV244APWRDGS
SN74LV244APWRDGSR

CAD (KiCad official)

Symbol: SN74LV244APWR
Footprint: Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm
3D model: TSSOP-20 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`sn74lv244apwr.step`	267 KB	You want the bare part, or you mark your own boards.
`sn74lv244apwr-etched.step`	2.7 MB	You want the part with `SN74LV244APWR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 700 faces against 327 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: Texas Instruments datasheet (42 pp, sha256 cd9506c8b2555370, retrieved 2026-08-17, tier: manufacturer)
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