SN74HCT244PWR 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 bank 1 (buffers 1A1-1A4 → 1Y1-1Y4). When low, bank 1 outputs pass the A input data. When high, bank 1 outputs are placed in the high-impedance state. Must be tied to VCC through a pull-up for high-Z during power up/down.
2	1A1	input	Bank 1 buffer input 1. TTL-compatible CMOS input; buffered non-inverting to 1Y1 when 1OE is low. VIH ≥ 2 V, VIL ≤ 0.8 V at VCC = 4.5-5.5 V; input current ≤ ±1 µA.
3	2Y4	tri_state	Bank 2 buffer output 4. 3-state, non-inverting output driven by 2A4 when 2OE is low; high-impedance when 2OE is high. ±6 mA output drive at 5 V.
4	1A2	input	Bank 1 buffer input 2. TTL-compatible CMOS input; buffered non-inverting to 1Y2 when 1OE is low.
5	2Y3	tri_state	Bank 2 buffer output 3. 3-state, non-inverting output driven by 2A3 when 2OE is low; high-impedance when 2OE is high.
6	1A3	input	Bank 1 buffer input 3. TTL-compatible CMOS input; buffered non-inverting to 1Y3 when 1OE is low.
7	2Y2	tri_state	Bank 2 buffer output 2. 3-state, non-inverting output driven by 2A2 when 2OE is low; high-impedance when 2OE is high.
8	1A4	input	Bank 1 buffer input 4. TTL-compatible CMOS input; buffered non-inverting to 1Y4 when 1OE is low.
9	2Y1	tri_state	Bank 2 buffer output 1. 3-state, non-inverting output driven by 2A1 when 2OE is low; high-impedance when 2OE is high.
10	GND	power_in	Device ground reference (0 V).
11	2A1	input	Bank 2 buffer input 1. TTL-compatible CMOS input; buffered non-inverting to 2Y1 when 2OE is low.
12	1Y4	tri_state	Bank 1 buffer output 4. 3-state, non-inverting output driven by 1A4 when 1OE is low; high-impedance when 1OE is high.
13	2A2	input	Bank 2 buffer input 2. TTL-compatible CMOS input; buffered non-inverting to 2Y2 when 2OE is low.
14	1Y3	tri_state	Bank 1 buffer output 3. 3-state, non-inverting output driven by 1A3 when 1OE is low; high-impedance when 1OE is high.
15	2A3	input	Bank 2 buffer input 3. TTL-compatible CMOS input; buffered non-inverting to 2Y3 when 2OE is low.
16	1Y2	tri_state	Bank 1 buffer output 2. 3-state, non-inverting output driven by 1A2 when 1OE is low; high-impedance when 1OE is high.
17	2A4	input	Bank 2 buffer input 4. TTL-compatible CMOS input; buffered non-inverting to 2Y4 when 2OE is low.
18	1Y1	tri_state	Bank 1 buffer output 1. 3-state, non-inverting output driven by 1A1 when 1OE is low; high-impedance when 1OE is high.
19	2OE	input	Active-low output enable for bank 2 (buffers 2A1-2A4 → 2Y1-2Y4). When low, bank 2 outputs pass the A input data. When high, bank 2 outputs are placed in the high-impedance state.
20	VCC	power_in	Positive supply rail, 4.5 V to 5.5 V (recommended). Absolute max 7 V. Decouple locally to GND with a 0.1 µF ceramic capacitor.

Key specifications

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

Ordering variants

Same part, different packaging or reel option.

SN74HCT244PWR
SN74HCT244PWRDB
SN74HCT244PWRDBR
SN74HCT244PWRDW
SN74HCT244PWRDWR
SN74HCT244PWRN
SN74HCT244PWRNS
SN74HCT244PWRNSR
SN74HCT244PWRDGS
SN74HCT244PWRDGSR
SN74HCT244PWRJ
SN74HCT244PWRFK

CAD (KiCad official)

Symbol: SN74HCT244PWR
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
`sn74hct244pwr.step`	267 KB	You want the bare part, or you mark your own boards.
`sn74hct244pwr-etched.step`	2.8 MB	You want the part with `SN74HCT244PWR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 727 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 (38 pp, sha256 5d3df17f40ffa6fd, 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