ATTINY87-XUR from Microchip Tech, in a TSSOP-20. 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	PA0	bidirectional	Port A bit 0 with selectable pull-up; alternate functions PCINT0, ADC0, RXD (UART receive) and RXLIN (LIN receive).
2	PA1	bidirectional	Port A bit 1 with selectable pull-up; alternate functions PCINT1, ADC1, TXD (UART transmit) and TXLIN (LIN transmit).
3	PA2	bidirectional	Port A bit 2 with selectable pull-up; alternate functions PCINT2, ADC2, OC0A, DO (USI data output) and MISO (SPI).
4	PA3	bidirectional	Port A bit 3 with selectable pull-up; alternate functions PCINT3, ADC3, ISRC (current source pin) and INT1.
5	AVCC	power_in	Analog supply voltage.
6	AGND	power_in	Analog ground.
7	PA4	bidirectional	Port A bit 4 with selectable pull-up; alternate functions PCINT4, ADC4, ICP1, DI/SDA (USI) and MOSI (SPI).
8	PA5	bidirectional	Port A bit 5 with selectable pull-up; alternate functions PCINT5, ADC5, T1, USCK/SCL (USI) and SCK (SPI).
9	PA6	bidirectional	Port A bit 6 with selectable pull-up; alternate functions PCINT6, ADC6, AIN0 (comparator negative input) and SS (SPI slave select).
10	PA7	bidirectional	Port A bit 7 with selectable pull-up; alternate functions PCINT7, ADC7, AIN1 (comparator positive input), XREF (internal reference output) and AREF (external ADC reference input).
11	PB7	bidirectional	Port B bit 7 with selectable pull-up; functions as RESET input (I/O only if RSTDISBL fuse is programmed) and dW (debugWIRE), plus PCINT15, ADC10 and OC1BX.
12	PB6	bidirectional	Port B bit 6 with selectable pull-up; alternate functions PCINT14, ADC9, OC1AX and INT0.
13	PB5	bidirectional	Port B bit 5 with selectable pull-up; alternate functions PCINT13, ADC8, OC1BW, XTAL2 (oscillator pin 2) and CLKO (divided system clock output).
14	PB4	bidirectional	Port B bit 4 with selectable pull-up; alternate functions PCINT12, OC1AW, XTAL1 (oscillator pin 1) and CLKI (external clock input).
15	VCC	power_in	Supply voltage (1.8 - 5.5V operating range).
16	GND	power_in	Ground.
17	PB3	bidirectional	Port B bit 3 with selectable pull-up; alternate functions PCINT11 and OC1BV.
18	PB2	bidirectional	Port B bit 2 with selectable pull-up; alternate functions PCINT10, OC1AV, USCK and SCL (USI default clock).
19	PB1	bidirectional	Port B bit 1 with selectable pull-up; alternate functions PCINT9, OC1BU and DO (USI default data output).
20	PB0	bidirectional	Port B bit 0 with selectable pull-up; alternate functions PCINT8, OC1AU, DI and SDA (USI default data input/output).

Key specifications

Parameter	Value
Manufacturer	Microchip Tech
Package	TSSOP-20
Category	Single Chip Microcomputer/Microcontroller
Pins	20

Electrical characteristics

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

Parameter	Symbol	Min	Typ	Max	Unit	Conditions	Page
Operating Temperature		-40		85	°C		250
Storage Temperature		-65		150	°C		250
Voltage on any Pin except RESET		-0.5		5.5	V	with respect to Ground; max printed as VCC+0.5V (5.5 is not printed; see review)	250
Voltage on RESET		-0.5		13	V	with respect to Ground	250
Voltage on VCC	VCC	-0.5		6	V	with respect to Ground	250
DC Current per I/O Pin				40	mA		250
DC Current VCC and GND Pins				200	mA		250
Injection Current		-5		5	mA	VCC = 0V to 5V	250
Supply voltage	VCC	1.8		5.5	V	TA = -40°C to +85°C	250
Input Low Voltage	VIL	-0.5		0.2	V	Except XTAL1 and RESET pins; max is 0.2 VCC	250
Input Low Voltage XTAL1	VIL1	-0.5		0.1	V	XTAL1 pin - External Clock Selected; max is 0.1 VCC	250
Input Low Voltage RESET	VIL2	-0.5		0.2	V	RESET pin; max is 0.2 VCC	250
Input Low Voltage RESET as I/O	VIL3	-0.5		0.2	V	RESET pin as I/O; max is 0.2 VCC	250
Input High Voltage	VIH	0.7			V	Except XTAL1 and RESET pins; min is 0.7 VCC, max VCC + 0.5 V	250
Input High Voltage XTAL1	VIH1	0.8			V	XTAL1 pin - External Clock Selected; min is 0.8 VCC, max VCC + 0.5 V	250
Input High Voltage RESET	VIH2	0.9			V	RESET pin; min is 0.9 VCC, max VCC + 0.5 V	250
Input High Voltage RESET as I/O	VIH3	0.7			V	RESET pin as I/O; min is 0.7 VCC, max VCC + 0.5 V	250
Output Low Voltage	VOL			0.6	V	IOL = 10 mA, VCC = 5V	250
Output Low Voltage	VOL			0.5	V	IOL = 5 mA, VCC = 3V	250
Output High Voltage	VOH	4.3			V	IOH = -10 mA, VCC = 5V	250
Output High Voltage	VOH	2.5			V	IOH = -5 mA, VCC = 3V	250
Input Leakage Current I/O Pin (pin low)	IIL		0.05	1	µA	VCC = 5.5V, pin low (absolute value)	250
Input Leakage Current I/O Pin (pin high)	IIH		0.05	1	µA	VCC = 5.5V, pin high (absolute value)	250
Reset Pull-up Resistor	RRST	30		60	kΩ		251
I/O Pin Pull-up Resistor	Rpu	20		50	kΩ		251
Power Supply Current Active Mode	ICC		5.5	7	mA	8 MHz, VCC = 5V, external clock	251
Power Supply Current Active Mode	ICC		1.8	2.5	mA	4 MHz, VCC = 3V, external clock	251
Power Supply Current Active Mode	ICC		0.3	0.6	mA	1 MHz, VCC = 2V, external clock	251
Power Supply Current Idle Mode	ICC		1.8	2.5	mA	8 MHz, VCC = 5V, external clock	251
Power Supply Current Idle Mode	ICC		0.5	0.8	mA	4 MHz, VCC = 3V, external clock	251
Power Supply Current Idle Mode	ICC		0.05	0.2	mA	1 MHz, VCC = 2V, external clock	251
Power Supply Current Power-down Mode	ICC		5	10	µA	WDT enabled, VCC = 3V	251
Power Supply Current Power-down Mode	ICC		0.15	4	µA	WDT disabled, VCC = 3V	251
Analog Comparator Input Offset Voltage	VACIO		10	40	mV	VCC = 5V, Vin = VCC/2	251
Analog Comparator Input Leakage Current	IACLK	-50		50	nA	VCC = 5V, Vin = VCC/2	251
Analog Comparator Propagation Delay	tACID		170		ns	VCC = 2.7V, common mode VCC/2	251
Analog Comparator Propagation Delay	tACID		180		ns	VCC = 5.0V, common mode VCC/2	251
Factory calibrated internal oscillator accuracy		-10	8	10	%	8.0 MHz, 3V, 25C	252
User calibrated internal oscillator accuracy		-1		1	%	7.3 - 8.1 MHz, 1.8 - 5.5V, -40C to +85C	252
Oscillator Frequency	1/tCLCL	0		4	MHz	Vcc = 1.8 - 5.5V	253
Oscillator Frequency	1/tCLCL	0		8	MHz	Vcc = 2.7 - 5.5V	253
Oscillator Frequency	1/tCLCL	0		16	MHz	Vcc = 4.5 - 5.5V	253
Bandgap reference voltage	VBG	1	1.1	1.2	V	VCC = 4.5, TA = 25°C	254
Brown-out threshold BODLEVEL=110	VBOT	1.7	1.8	2	V	BODLEVEL[2:0] = 110b	254
Brown-out threshold BODLEVEL=101	VBOT	2.5	2.7	2.9	V	BODLEVEL[2:0] = 101b	254
Brown-out threshold BODLEVEL=100	VBOT	4.1	4.3	4.5	V	BODLEVEL[2:0] = 100b	254
Power-on Reset Threshold Voltage (falling)	VPOT	1	1.3	1.6	V	falling	253
Current Source current	IISRC	94		106	µA	VCC = 2.7 V / 5.5 V, T = -40°C / +85°C	255
ADC absolute accuracy single ended	TUE		2	3.5	LSB	VCC = 4V, VRef = 4V, ADC clock = 200 kHz	255
ADC INL single ended	INL		0.6	2	LSB	VCC = 4V, VRef = 4V, ADC clock = 200 kHz	255
ADC DNL single ended	DNL		0.3	0.8	LSB	VCC = 4V, VRef = 4V, ADC clock = 200 kHz	255
ADC gain error single ended	Gain error	-6	-2.5	2	LSB	VCC = 4V, VRef = 4V, ADC clock = 200 kHz	255
ADC offset error single ended	Offset error	-3.5	1.5	3.5	LSB	VCC = 4V, VRef = 4V, ADC clock = 200 kHz	255
Internal 1.1V reference	VINT	1	1.1	1.2	V		255
Internal 2.56V reference	VINT	2.3	2.56	2.8	V	VCC > 3.0V	255
External voltage reference single ended	AREF	2			V	Single Ended Conversions; max AVCC	255

CAD (KiCad official)

Symbol: ATTINY87-XUR
Footprint: Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm
3D model: TSSOP-20 (KiCad packages3D, STEP)
3D model files: attiny87-xur-etched.step / attiny87-xur-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); attiny87-xur.step / attiny87-xur.glb are the bare package body.

Provenance

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

Datasheet: Microchip Tech datasheet (303 pp, sha256 bd44c151eaf787c8, retrieved 2026-10-30, tier: manufacturer)
Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-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

ATTINY87-XUR

Verified ATTINY87-XUR

Verification log 1 record

3D Model

Symbol & Footprint

Schematic Symbol

PCB Footprint

Datasheet

README