AMC6821SQDBQRQ1 from Texas Instruments, in a SSOP-16-150mil. 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	PWM-OUT	output	Digital output, open-drain, providing the PWM output that controls fan speed.
2	TACH	input	Digital input for the fan tachometer, used to measure fan speed.
3	OVR	output	Digital output, open-drain, active low; goes low when temperature reaches the critical shutdown threshold or the remote temperature sensor has failed.
4	NC	unconnected	Not connected; reserved for manufacturer's testing.
5	GND	power_in	System ground.
6	VDD	power_in	Power supply input, 3 V to 5 V per the pin table; recommended operating VDD is 2.7 V to 5.5 V.
7	THERM	bidirectional	Open-drain I/O: as an output, active low indicates temperature over the THERM limit; as an input, pulling it low sets the THERM-IN bit and drives the fan to full speed.
8	FAN-FAULT	output	Digital open-drain output that goes low when a fan failure is detected.
9	IN-	input	Negative analog differential input, connected to the cathode of the external temperature-sensing diode.
10	IN+	input	Positive analog differential input, connected to the anode of the external temperature-sensing diode (Pentium-IV substrate transistor or 2N3904-type transistor).
11	PWM-MODE	input	PWM frequency range select, checked only on power-up or reset: tied to GND selects the high range (1 kHz to 40 kHz); tied to VDD or floated selects the low range (10 Hz to 94 Hz).
12	A1	input	Device slave address select bit, checked only on power-up or reset; tie to VDD or GND (NC allowed per the address table).
13	A0	input	Device slave address select bit, checked only on power-up or reset; tie to VDD or GND (NC allowed per the address table).
14	SMBALERT	output	Digital open-drain output, active low; requires a pullup resistor (2.2 kΩ typical).
15	SDA	bidirectional	Bidirectional open-drain SMBus data pin; requires a pullup resistor (2.2 kΩ typical).
16	SCLK	input	SMBus clock input; requires a pullup resistor (2.2 kΩ typical).

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SSOP-16-150mil
Category	Sensors
Pins	16

Electrical characteristics

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

Parameter	Symbol	Min	Typ	Max	Unit	Conditions	Page
VDD to GND		-0.3		6.5	V		4
Digital input voltage to GND		-0.3		6.5	V		4
Input current				10	mA		4
Select pins A0, A1, PWM-MODE to GND		-0.3			V		4
Analog input voltage to GND		-0.3			V		4
Operating temperature		-40		125	°C		4
Junction temperature (TJ Max)	TJ			150	°C		4
Storage temperature		-65		150	°C		4
Operating VDD	VDD	2.7	5	5.5	V		4
Specified VDD	VDD	3		5	V		4
Operating temperature		-40		125	°C		4
Local sensor accuracy		-3	0.5	3	°C	TA = 0°C to 90°C	5
Local sensor accuracy		-4	1	4	°C	TA = -25°C to 100°C	5
Remote sensor accuracy		-3	0.5	3	°C	TR = 50°C to 100°C	5
Remote sensor accuracy		-4	1	4	°C	TR = -40°C to 125°C	5
PWM frequency range (programmable)		10			Hz		5
PWM frequency accuracy		-6		7	%	TA = 25°C to 100°C	5
Duty cycle (programmable)		0		100	%	Programmable	5
Fan RPM-to-digital converter accuracy		-6		7	%	TA = 25°C to 100°C	5
Nominal input RPM		100		23000	RPM		5
Open-drain output low voltage	VOL	0		0.4	V	Sink current 6 mA, VDD = 3 V	5
Open-drain high-level output leakage current	IOH		0.1	1	μA		5
Input high voltage	VIH	2.1			V		5
Input low voltage	VIL			0.8	V		5
Input high current	IIH	-1			μA		5
Input low current	IIL			1	μA		5
Supply current			1.1	2	mA	VDD = 5	5
fSCLK clock frequency	fSCLK			100	kHz		5
Bus free time	tBUF	4.7			μs		5
Start setup time	tSU:STA	4.7			μs		5
Start hold time	tHD:STA	4			μs		5
Stop condition setup time	tSU:STO	4			μs		5
SCLK low time	tLOW	4.7			μs		5
SCLK high time	tHIGH	4			μs		5
SCLK, SDA rise time	tR			1000	ns		5
SCLK, SDA fall time	tF			300	ns		6
Data setup time	tSU:DAT	350			ns		6
Data hold time	tHD:DAT	350			ns		6
Time from software reset command or power-on to normal operation	tPOR			1.5	ms		6
Junction-to-ambient thermal resistance	RθJA		97.6		°C/W		4
Junction-to-case (top) thermal resistance	RθJC(top)		44.6		°C/W		4
Junction-to-board thermal resistance	RθJB		41.2		°C/W		4
Junction-to-top characterization parameter	ψJT		5.7		°C/W		4
Junction-to-board characterization parameter	ψJB		40.7		°C/W		4

CAD (KiCad official)

Symbol: AMC6821SQDBQRQ1
Footprint: Package_SO:SSOP-16_3.9x4.9mm_P0.635mm
3D model: SSOP-16-150mil (KiCad packages3D, STEP)
3D model files: amc6821sqdbqrq1-etched.step / amc6821sqdbqrq1-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); amc6821sqdbqrq1.step / amc6821sqdbqrq1.glb are the bare package body.

Provenance

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

Datasheet: Texas Instruments datasheet (56 pp, sha256 d968d3f762622bc4, retrieved 2026-11-13, 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).

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AMC6821SQDBQRQ1

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3D Model

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