MAX3221EETE+T from Maxim Integrated, in a TQFN-16-EP(5x5). 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	C1-	passive	Negative terminal of the voltage doubler Charge-Pump Capacitor.
2	C2+	passive	Positive terminal of the inverting Charge-Pump Capacitor.
3	C2-	passive	Negative terminal of the inverting Charge-Pump Capacitor.
4	V-	power_out	-5.5V generated by the charge pump.
5	R1IN	input	RS-232 receiver input.
6	R1OUT	output	TTL/CMOS receiver output.
7	INVALID	output	Output of the valid signal detector; INVALID is enabled high if a valid RS-232 level is present on any receiver input.
8	T1IN	input	TTL/CMOS transmitter input.
9	FORCEON	input	Drive high to override automatic circuitry keeping transmitters and charge pump on (FORCEOFF must be high).
10	T1OUT	output	RS-232 transmitter output.
11	GND	power_in	Ground.
12	VCC	power_in	+3.0V to +5.5V supply voltage.
13	FORCEOFF	input	Force-Off input, active low; drive low to shut down transmitters, receivers and the on-board charge pump, overriding all automatic circuitry and FORCEON.
14	EN	input	Receiver enable control; drive low for normal operation and high to force the receiver outputs (R_OUT) into a high-impedance state.
15	V+	power_out	+5.5V generated by the charge pump.
16	C1+	passive	Positive terminal of the voltage doubler Charge-Pump Capacitor.
17	EP	passive	Exposed pad (from the footprint; not named in the datasheet pin table).

Key specifications

Parameter	Value
Manufacturer	Maxim Integrated
Package	TQFN-16-EP(5x5)
Category	Interface ICs
Pins	17

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 Logic Threshold Low				0.8	V	VCC = 3.3V or 5.0V, TA = +25°C	2
Input Logic Threshold High		2.4			V	VCC = 3.3V or 5.0V, TA = +25°C	2
Input Leakage Current T_IN, EN, FORCEON, FORCEOFF		-1	0.01	1	µA	VCC = 3.3V or 5.0V, TA = +25°C	2
Output Voltage Low (R_OUT)				0.4	V	IOUT = 1.6mA	2
INVALID Output Voltage Low				0.4	V		2
Receiver Input Threshold to INVALID Output Low		-0.3		0.3	V	Figure 5a	2
Receiver Input Threshold to INVALID Output High		-2.7		2.7	V	Figure 5a	2
Supply Current, AutoShutdown Disabled	ICC		0.3	1	mA	FORCEON = FORCEOFF = VCC, no load	2
Supply Current, Shutdown	ICC		1	10	µA	FORCEOFF = GND, all R_IN = GND	2
Supply Current, AutoShutdown	ICC		1	10	µA	FORCEON = GND, FORCEOFF = VCC, all R_IN open	2
Output Leakage Current (R_OUT, receivers disabled)		-10	0.05	10	µA	R_OUT receivers disabled	2
Output Leakage Current (T_OUT)		-25		25	µA	VOUT = ±12V, VCC = 0 or 3V to 5.5V, transmitters disabled	3
Output Short-Circuit Current		-60		60	mA		3
Output Resistance		300			Ω	VCC = V+ = V- = 0, TOUT = ±2V	3
Output Voltage Swing		-5	5.4		V	All transmitter outputs loaded with 3kΩ to ground	3
Input Threshold Low (VCC = 3.3V)		0.6	1.2		V	VCC = 3.3V	3
Input Threshold Low (VCC = 5.0V)		0.8	1.5		V	VCC = 5.0V	3
Input Threshold High (VCC = 3.3V)		1.5	2.4		V	VCC = 3.3V	3
Input Threshold High (VCC = 5.0V)		1.8	2.4		V	VCC = 5.0V	3
Input Resistance		3	5	7	kΩ		3
Input Voltage Range (R_IN)		-25		25	V		3
Maximum Data Rate		250			kbps		4
Transition-Region Slew Rate		6		30	V/µs	VCC = 3.3V, RL = 3kΩ to 7kΩ, CL = 150pF, TA = +25°C, measured from +3V to -3V or -3V to +3V, one transmitter switching	4
Supply Voltage VCC	VCC	3		5.5	V	Electrical characteristics test range VCC = +3.0V to +5.5V	2
Operating Temperature (MAX32__EE__)	TA	-40		85	°C	Extended temperature grade (MAX3221EETE+)	2
VCC to GND	VCC	-0.3		6	V		2
V+ to GND	V+	-0.3		7	V	Note 1	2
V- to GND	V-	-7		0.3	V	Note 1	2
V+ + /V-/				13	V	Note 1	2
T_IN, EN, FORCEON, FORCEOFF to GND		-0.3		6	V		2
R_IN to GND		-25		25	V		2
T_OUT to GND		-13.2		13.2	V		2
R_OUT, R2OUTB, INVALID to GND		-0.3			V	Maximum printed as VCC + 0.3V	2
Storage Temperature Range	TSTG	-65		160	°C		2
Lead Temperature (soldering, 10s)				300	°C	soldering, 10s	2
Soldering Temperature (reflow)				260	°C	reflow	2
Derating above +70°C (16-Pin TQFN)			20.8		mW/°C	above +70°C, 16-Pin TQFN	2

CAD (KiCad official)

Symbol: MAX3221EETE+T
Footprint: Package_DFN_QFN:QFN-16-1EP_5x5mm_P0.8mm_EP2.7x2.7mm
3D model: TQFN-16-EP(5x5) (KiCad packages3D, STEP)
3D model files: max3221eete-t-etched.step / max3221eete-t-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); max3221eete-t.step / max3221eete-t.glb are the bare package body.

Provenance

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

Datasheet: Maxim Integrated datasheet (19 pp, sha256 05825bd0ffbc0555, 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

MAX3221EETE+T

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3D Model

Symbol & Footprint

Schematic Symbol

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Datasheet

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