AT28BV64B-20SU-T from Microchip Tech, in a SOIC-28-300mil. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	NC	unconnected	No connect; the pin is not internally connected.
2	A12	input	Address input A12; A6 to A12 define the page that all bytes of a page write must reside on.
3	A7	input	Address input A7; A6 to A12 define the page that all bytes of a page write must reside on.
4	A6	input	Address input A6; A6 to A12 define the page that all bytes of a page write must reside on.
5	A5	input	Address input A5; A0 to A5 select which byte within the 64-byte page is written.
6	A4	input	Address input A4; A0 to A5 select which byte within the 64-byte page is written.
7	A3	input	Address input A3; A0 to A5 select which byte within the 64-byte page is written.
8	A2	input	Address input A2; A0 to A5 select which byte within the 64-byte page is written.
9	A1	input	Address input A1; A0 to A5 select which byte within the 64-byte page is written.
10	A0	input	Address input A0; A0 to A5 select which byte within the 64-byte page is written.
11	I/O0	bidirectional	Data input/output bit 0 for read data and write data.
12	I/O1	bidirectional	Data input/output bit 1 for read data and write data.
13	I/O2	bidirectional	Data input/output bit 2 for read data and write data.
14	GND	power_in	Device ground; all input and output voltage limits are specified with respect to ground.
15	I/O3	bidirectional	Data input/output bit 3 for read data and write data.
16	I/O4	bidirectional	Data input/output bit 4 for read data and write data.
17	I/O5	bidirectional	Data input/output bit 5 for read data and write data.
18	I/O6	bidirectional	Data input/output bit 6; it toggles during a write cycle and can be used as a toggle-bit end-of-write indicator.
19	I/O7	bidirectional	Data input/output bit 7; DATA polling on this pin shows the complement of the written data until the write cycle ends.
20	CE	input	Chip enable; read requires CE low, and when CE is high the outputs are high impedance.
21	A10	input	Address input A10; A6 to A12 define the page that all bytes of a page write must reside on.
22	OE	input	Output enable; with CE low and WE high, data is driven onto the I/O pins when OE is low.
23	A11	input	Address input A11; A6 to A12 define the page that all bytes of a page write must reside on.
24	A9	input	Address input A9; raising it to 12V ±0.5V accesses the 64-byte device identification area at addresses 0000H to 003FH.
25	A8	input	Address input A8; A6 to A12 define the page that all bytes of a page write must reside on.
26	NC	unconnected	No connect; the pin is not internally connected.
27	WE	input	Write enable; a low pulse on WE with CE low and OE high initiates a write cycle.
28	VCC	power_in	Power supply; 2.7V to 3.6V for the AT28BV64B-20 operating range.

Key specifications

Parameter	Value
Manufacturer	Microchip Tech
Package	SOIC-28-300mil
Category	Memory
Pins	28

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter	Symbol	Min	Typ	Max	Unit	Conditions	Page
Temperature Under Bias		-55		125	°C		5
Storage Temperature		-65		150	°C		5
All Input Voltages (including NC Pins) with Respect to Ground		-0.6		6.25	V		5
All Output Voltages with Respect to Ground		-0.6			V	Upper limit printed as VCC + 0.6 V	5
Voltage on OE and A9 with Respect to Ground		-0.6		13.5	V		5
Operating Temperature (Case)		-40		85	°C	AT28BV64B-20	5
VCC Power Supply	VCC	2.7		3.6	V	AT28BV64B-20	5
Input Load Current	ILI			10	µA	VIN = 0V to VCC + 1V	6
Output Leakage Current	ILO			10	µA	VI/O = 0V to VCC	6
VCC Standby Current CMOS	ISB			50	µA	CE = VCC - 0.3V to VCC + 1V	6
VCC Active Current	ICC			15	mA	f = 5 MHz; IOUT = 0 mA	6
Input Low Voltage	VIL			0.6	V		6
Input High Voltage	VIH	2			V		6
Output Low Voltage	VOL			0.45	V	IOL = 1.6 mA	6
Output High Voltage	VOH	2			V	IOH = -100 µA	6
Input Pin Capacitance	CIN		4	6	pF	f = 1 MHz, T = 25°C; VIN = 0V	7
Output Pin Capacitance	COUT		8	12	pF	f = 1 MHz, T = 25°C; VOUT = 0V	7
Address to Output Delay	tACC			200	ns		6
CE to Output Delay	tCE			200	ns		6
OE to Output Delay	tOE	0		80	ns		6
CE or OE to Output Float	tDF	0		55	ns	CL = 5pF (note 3)	6
Output Hold from OE, CE or Address, Whichever Occurred First	tOH	0			ns		6
Address, OE Set-up Time	tAS,tOES	0			ns		8
Address Hold Time	tAH	100			ns		8
Chip Select Set-up Time	tCS	0			ns		8
Chip Select Hold Time	tCH	0			ns		8
Write Pulse Width (WE or CE)	tWP	200			ns		8
Data Set-up Time	tDS	100			ns		8
Data, OE Hold Time	tDH,tOEH	0			ns		8
Write Pulse Width High	tWPH	100			ns		8
Write Cycle Time	tWC			10	ms		9
Address Set-up Time	tAS	0			ns		9
Address Hold Time	tAH	100			ns		9
Data Set-up Time	tDS	100			ns		9
Data Hold Time	tDH	0			ns		9
Write Pulse Width	tWP	200			ns		9
Byte Load Cycle Time	tBLC			100	µs		9
Write Pulse Width High	tWPH	100			ns		9
Data Hold Time (Data Polling)	tDH	0			ns		10
OE Hold Time (Data Polling)	tOEH	0			ns		10
Write Recovery Time (Data Polling)	tWR	0			ns		10
Data Hold Time (Toggle Bit)	tDH	10			ns		11
OE Hold Time (Toggle Bit)	tOEH	10			ns		11
OE High Pulse	tOEHP	150			ns		11
Write Recovery Time (Toggle Bit)	tWR	0			ns		11

CAD (KiCad official)

Symbol: AT28BV64B-20SU-T
Footprint: Package_SO:SOIC-28W_7.5x17.9mm_P1.27mm
3D model: SOIC-28-300mil (KiCad packages3D, STEP)
3D model files: at28bv64b-20su-t-etched.step / at28bv64b-20su-t-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); at28bv64b-20su-t.step / at28bv64b-20su-t.glb are the bare package body.

Provenance

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

Datasheet: Microchip Tech datasheet (17 pp, sha256 d0489c27bca44b69, retrieved 2026-11-12, tier: manufacturer)
Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF

AT28BV64B-20SU-T

Verified AT28BV64B-20SU-T

Verification log 1 record

3D Model

Symbol & Footprint

Schematic Symbol

PCB Footprint

Datasheet

README