MAX4209HAUA+ from Maxim Integrated, in a MSOP-8. 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	REFIN/MODE	input	Trimode input: connect to VDD for shutdown (about 1.4µA), to an external reference or resistive divider between VSS + 0.2V and VDD - 1.3V to buffer it onto REF, or to VSS to put the internal REF buffer output in high impedance for direct drive of REF.
2	IN-	input	Negative differential input; the maximum recommended differential input voltage is ±100mV, and linearity and accuracy degrade above that level.
3	IN+	input	Positive differential input; the maximum recommended differential input voltage is ±100mV, and linearity and accuracy degrade above that level.
4	VSS	power_in	Negative supply input; bypass to ground with a 0.1µF capacitor or connect to ground for single-supply operation (2.85V to 5.5V total supply).
5	REF	input	Output reference level that sets the OUT voltage for zero differential input; it is set by the internal buffer when REFIN/MODE is between VSS + 0.2V and VDD - 1.3V, and must be driven directly by a low-impedance reference only when REFIN/MODE is at VSS.
6	FB	input	Feedback input: on the MAX4208 connect to the center tap of an OUT-to-REF resistive divider to set gain, while on the MAX4209 it is internally connected to the gain-setting resistors; an optional CFB from OUT to FB (1nF to 10nF recommended) reduces autozero noise.
7	OUT	output	Amplifier output with rail-to-rail capability; in unipolar operation it can only swing to within 40mV of ground (VSS), and the device drives capacitive loads up to 200pF.
8	VDD	power_in	Positive supply input; bypass to ground with a 0.1µF capacitor (single-supply range 2.85V to 5.5V).

Key specifications

Parameter	Value
Manufacturer	Maxim Integrated
Package	MSOP-8
Category	Interface ICs
Pins	8

Electrical characteristics

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

Parameter	Symbol	Min	Typ	Max	Unit	Conditions	Page
Input Offset Voltage (MAX4209H, G = 100V/V)	VOS	-20	3	20	µV	MAX4209H, G = 100V/V	2
Gain Error		-0.25	0.05	0.25	%	-20mV ≤ VDIFF ≤ +20mV, MAX4209H, G = 100V/V	2
Gain Nonlinearity			25	150	ppm	MAX4209H, G = 100V/V	2
Input Common-Mode Rejection Ratio	CMRR	106	135		dB	VCM = (VSS - 0.1V) to (VDD - 1.30V)	2
Power-Supply Rejection Ratio	PSRR	100	125		dB	VDD = 2.85V to 5.5V, VREF = VCM = (VSS + 0.5V)	3
REFIN/MODE Buffer Input Offset Voltage		-40	10	40	µV		3
REFIN/MODE Buffer Common-Mode Rejection Ratio		106	135		dB	(VSS + 0.2V) ≤ VREF/MODE ≤ (VDD - 1.3V) (Note 2)	3
REFIN/MODE Buffer Power-Supply Rejection Ratio		100	125		dB	VDD = 2.85V to 5.5V, VREF/MODE = VCM = (VSS + 0.5V)	3
REF Common-Mode Rejection Ratio		106	135		dB	VSS ≤ VREF ≤ (VDD - 1.30V) (Note 4)	3
REF Input Current (MAX4209)	IREF	-10		10	nA	VDIFF = 0V (Note 5)	3
REF Input Current (MAX4209)	IREF	-100		100	µA	VDIFF = ±100mV (Note 5)	3
Output Voltage Swing High	VOH		30	45	mV	RL = 100kΩ	3
Output Voltage Swing High	VOH		50	70	mV	RL = 10kΩ	3
Output Voltage Swing High	VOH		250	325	mV	RL = 1kΩ	3
Output Voltage Swing Low	VOL		30	40	mV	RL = 100kΩ	3
Output Voltage Swing Low	VOL		50	65	mV	RL = 10kΩ	3
Output Voltage Swing Low	VOL		250	285	mV	RL = 1kΩ	3
Short-Circuit Current, Source	ISC			20	mA	Source	3
Short-Circuit Current, Sink	ISC	-25			mA	Sink	3
Maximum Capacitive Load	CL			200	pF	No sustained oscillations	4
Supply Voltage	VDD	2.85		5.5	V	Guaranteed by PSRR test	4
Supply Current, buffer OFF	IDD		0.75	1.3	mA	VREFIN/MODE = VSS, buffer OFF, VDD = 5V	4
Supply Current, buffer ON	IDD		1.4	2.3	mA	(VSS + 0.2V) ≤ VREFIN/MODE ≤ (VDD - 1.3V), buffer ON, VDD = 5V	4
Supply Current, shutdown	IDD		1.4	5	µA	VREFIN/MODE = VDD, shutdown mode	4
Input Offset Voltage (MAX4209H)	VOS	-30		30	µV	MAX4209H, G = 100V/V, TA = +25°C to +85°C	4
Input Offset Voltage (MAX4209H)	VOS	-40		40	µV	MAX4209H, G = 100V/V, TA = -40°C to +125°C	4
Input Offset Voltage Temperature Drift (MAX4209H)	TCVOS	-0.17	0.01	0.17	µV/°C	MAX4209H, G = 100V/V, TA = +25°C to +85°C	4
Gain Error (MAX4209H)				0.3	%	-20mV ≤ VDIFF ≤ +20mV, G = 100V/V, TA = +25°C to +85°C	4
Gain Error (MAX4209H)				0.35	%	-20mV ≤ VDIFF ≤ +20mV, G = 100V/V, TA = -40°C to +125°C	4
Gain Error Temperature Drift			50	180	ppm/°C	-20mV ≤ VDIFF ≤ +20mV, G = 100V/V, TA = -40°C to +125°C	5
Gain Nonlinearity (MAX4209H)	GNL			210	ppm	G = 100V/V, TA = +25°C to +85°C	5
Gain Nonlinearity (MAX4209H)	GNL			700	ppm	G = 100V/V, TA = -40°C to +125°C	5
Input Common-Mode Rejection Ratio	CMRR	96			dB	(VSS - 0.1V) ≤ VCM ≤ (VDD - 1.6V), TA = +25°C to +85°C	5
Input Common-Mode Rejection Ratio	CMRR	90			dB	(VSS - 0.1V) ≤ VCM ≤ (VDD - 1.6V), TA = -40°C to +125°C	5
Power-Supply Rejection Ratio	PSRR	96			dB	VDD = 2.85V to 5.5V, VREF = VCM = VSS + 0.5V, TA = +25°C to +85°C	5
Power-Supply Rejection Ratio	PSRR	90			dB	VDD = 2.85V to 5.5V, VREF = VCM = VSS + 0.5V, TA = -40°C to +125°C	5
REFIN/MODE Buffer Input Offset Voltage				100	µV	TA = +25°C to +85°C	5
REFIN/MODE Buffer Common-Mode Rejection Ratio		96			dB	(VSS + 0.2V) ≤ VREF ≤ (VDD - 1.6V), TA = +25°C to +85°C	6
REFIN/MODE Buffer Common-Mode Rejection Ratio		90			dB	(VSS + 0.2V) ≤ VREF ≤ (VDD - 1.6V), TA = -40°C to +125°C	6
REF Common-Mode Rejection Ratio		96			dB	VSS ≤ VREF ≤ (VDD - 1.6V), TA = +25°C to +85°C	6
REF Common-Mode Rejection Ratio		90			dB	VSS ≤ VREF ≤ (VDD - 1.6V), TA = -40°C to +125°C	6
REFIN/MODE Buffer Power-Supply Rejection Ratio		96			dB	VDD = 2.85V to 5.5V, VREFIN/MODE = VCM = (VSS + 0.5V), TA = +25°C to +85°C	6
REFIN/MODE Buffer Power-Supply Rejection Ratio		90			dB	VDD = 2.85V to 5.5V, VREFIN/MODE = VCM = (VSS + 0.5V), TA = -40°C to +125°C	6
Output Voltage Swing High (over temperature)	VOH			60	mV	RL = 100kΩ, TA = -40°C to +125°C	6
Output Voltage Swing High (over temperature)	VOH			90	mV	RL = 10kΩ, TA = -40°C to +125°C	6
Output Voltage Swing High (over temperature)	VOH			375	mV	RL = 1kΩ, TA = -40°C to +125°C	6
Output Voltage Swing Low (over temperature)	VOL			50	mV	RL = 100kΩ, TA = -40°C to +125°C	6
Output Voltage Swing Low (over temperature)	VOL			75	mV	RL = 10kΩ, TA = -40°C to +125°C	6
Output Voltage Swing Low (over temperature)	VOL			325	mV	RL = 1kΩ, TA = -40°C to +125°C	6
Supply Current, buffer OFF (over temperature)	IDD			1.7	mA	VREFIN/MODE = VSS, buffer OFF, VDD = 5V, TA = -40°C to +125°C	6
Supply Current, buffer ON (over temperature)	IDD			3	mA	(VSS + 0.2V) ≤ VREFIN/MODE ≤ (VDD - 1.6V), buffer ON, VDD = 5V, TA = -40°C to +125°C	6
Supply Current, shutdown (over temperature)	IDD			10	µA	REFIN/MODE = VDD, shutdown mode, TA = -40°C to +125°C	6
Operating Temperature Range		-40		125	°C		2
VDD to VSS		-0.3		6	V		2
Current Into OUT, VDD, and VSS		-25		25	mA		2
Current Into Any Other Pin		-20		20	mA		2
Junction Temperature				150	°C		2
Storage Temperature Range		-65		150	°C		2
Lead Temperature				300	°C	soldering, 10 s	2

CAD (KiCad official)

Symbol: MAX4209HAUA+
Footprint: Package_SO:MSOP-8_3x3mm_P0.65mm
3D model: MSOP-8 (KiCad packages3D, STEP)
3D model files: max4209haua-etched.step / max4209haua-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); max4209haua.step / max4209haua.glb are the bare package body.

Provenance

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

Datasheet: Maxim Integrated datasheet (17 pp, sha256 6968bc307add7a81, retrieved 2026-10-30, 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

MAX4209HAUA+

Verified MAX4209HAUA+

Verification log 1 record

3D Model

Symbol & Footprint

Schematic Symbol

PCB Footprint

Datasheet

README