MC74ACT244DTR2G from onsemi, in a ETSSOP-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	~{OE1}	input	Active-low output enable for bank 1 (drives outputs 1Y1-1Y4 on pins 18, 16, 14, 12). LOW = outputs follow inputs; HIGH = outputs are high-impedance (Z).
2	1A1	input	Bank 1 data input 1. Buffered through to 1Y1 (pin 18) when /OE1 is LOW.
3	2Y4	tri_state	Bank 2 3-state output 4. Reflects 2A4 (pin 17) when /OE2 is LOW; high-impedance when /OE2 is HIGH. Sources/sinks up to 24 mA.
4	1A2	input	Bank 1 data input 2. Buffered through to 1Y2 (pin 16) when /OE1 is LOW.
5	2Y3	tri_state	Bank 2 3-state output 3. Reflects 2A3 (pin 15) when /OE2 is LOW; high-impedance when /OE2 is HIGH.
6	1A3	input	Bank 1 data input 3. Buffered through to 1Y3 (pin 14) when /OE1 is LOW.
7	2Y2	tri_state	Bank 2 3-state output 2. Reflects 2A2 (pin 13) when /OE2 is LOW; high-impedance when /OE2 is HIGH.
8	1A4	input	Bank 1 data input 4. Buffered through to 1Y4 (pin 12) when /OE1 is LOW.
9	2Y1	tri_state	Bank 2 3-state output 1. Reflects 2A1 (pin 11) when /OE2 is LOW; high-impedance when /OE2 is HIGH.
10	GND	power_in	Ground reference (0 V) for logic and outputs.
11	2A1	input	Bank 2 data input 1. Buffered through to 2Y1 (pin 9) when /OE2 is LOW.
12	1Y4	tri_state	Bank 1 3-state output 4. Reflects 1A4 (pin 8) when /OE1 is LOW; high-impedance when /OE1 is HIGH.
13	2A2	input	Bank 2 data input 2. Buffered through to 2Y2 (pin 7) when /OE2 is LOW.
14	1Y3	tri_state	Bank 1 3-state output 3. Reflects 1A3 (pin 6) when /OE1 is LOW; high-impedance when /OE1 is HIGH.
15	2A3	input	Bank 2 data input 3. Buffered through to 2Y3 (pin 5) when /OE2 is LOW.
16	1Y2	tri_state	Bank 1 3-state output 2. Reflects 1A2 (pin 4) when /OE1 is LOW; high-impedance when /OE1 is HIGH.
17	2A4	input	Bank 2 data input 4. Buffered through to 2Y4 (pin 3) when /OE2 is LOW.
18	1Y1	tri_state	Bank 1 3-state output 1. Reflects 1A1 (pin 2) when /OE1 is LOW; high-impedance when /OE1 is HIGH.
19	~{OE2}	input	Active-low output enable for bank 2 (drives outputs 2Y1-2Y4 on pins 9, 7, 5, 3). LOW = outputs follow inputs; HIGH = outputs are high-impedance (Z).
20	VCC	power_in	Supply voltage. Recommended 4.5-5.5 V for 'ACT variant (TTL-compatible inputs). Absolute max -0.5 to +7.0 V.

Key specifications

Parameter	Value
Manufacturer	onsemi
Package	ETSSOP-20
Category	Logic
Pins	20

Ordering variants

Same part, different packaging or reel option.

MC74ACT244DTR2G
MC74ACT244DTR2GDWG
MC74ACT244DTR2GDWR2G

CAD (KiCad official)

Symbol: MC74ACT244DTR2G
Footprint: Package_SO:ETSSOP-20-1EP_4.4x6.5mm_P0.65mm_EP3x4.2mm
3D model: ETSSOP-20 (KiCad packages3D, STEP)

Provenance

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

Datasheet: onsemi datasheet (7 pp, sha256 b452f9bb0cbf3736, 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