MAX3221CUE+T from Maxim Integrated, in a TSSOP-16. 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	EN	input	Receiver Enable Control: drive low for normal operation and high to force the receiver outputs into a high-Z state.
2	C1+	passive	Positive terminal of the voltage doubler charge-pump capacitor.
3	V+	power_out	+5.5V generated by the charge pump, regardless of VCC over the +3.0V to +5.5V range.
4	C1-	passive	Negative terminal of the voltage doubler charge-pump capacitor.
5	C2+	passive	Positive terminal of the inverting charge-pump capacitor.
6	C2-	passive	Negative terminal of the inverting charge-pump capacitor.
7	V-	power_out	-5.5V generated by the inverting charge pump, regardless of VCC over the +3.0V to +5.5V range.
8	R1IN	input	RS-232 receiver input, with a voltage range of -25V to +25V and a typical input resistance of 3 to 7 kΩ.
9	R1OUT	output	TTL/CMOS receiver output, inverting and three-state, that is active in shutdown and AutoShutdown.
10	INVALID	output	Output of the valid signal detector that is high when a valid RS-232 level is present on the receiver inputs.
11	T1IN	input	TTL/CMOS transmitter input, which the transmitter inverts to RS-232 levels of ±5.0V minimum.
12	FORCEON	input	Drive high to override the automatic circuitry and keep the transmitters on (FORCEOFF must be high).
13	T1OUT	output	RS-232 transmitter output with a swing of ±5.0V minimum into a 3kΩ load and ±60mA typical short-circuit current.
14	GND	power_in	Ground reference for the device.
15	VCC	power_in	Supply voltage input of +3.0V to +5.5V.
16	FORCEOFF	input	Drive low to shut down the transmitters and the on-board power supply, overriding all automatic circuitry and FORCEON.

Key specifications

Parameter	Value
Manufacturer	Maxim Integrated
Package	TSSOP-16
Category	Interface ICs
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
Supply Current, AutoShutdown			1	10	µA	VCC = 3.3V or 5.0V, TA = +25°C; All R_IN open, FORCEON = GND, FORCEOFF = VCC	2
Supply Current, Shutdown			1	10	µA	FORCEOFF = GND	2
Supply Current, AutoShutdown Disabled			0.3	1	mA	FORCEON = FORCEOFF = VCC, no load	2
Input Logic Threshold Low				0.8	V	T_IN, FORCEON, FORCEOFF, EN (MAX3223)	2
Input Logic Threshold High		2			V	T_IN, EN, FORCEON, FORCEOFF; VCC = 3.3V	2
Input Logic Threshold High		2.4			V	T_IN, EN, FORCEON, FORCEOFF; VCC = 5.0V	2
Input Leakage Current		-1	0.01	1	µA	T_IN, EN, FORCEON, FORCEOFF	2
Output Leakage Current		-10	0.05	10	µA	Receivers disabled	2
Output Voltage Low				0.4	V	IOUT = 1.6mA	2
Receiver Input Thresholds to Transmitters Enabled, Positive threshold		2.7			V	Figure 5	2
Receiver Input Thresholds to Transmitters Enabled, Negative threshold				-2.7	V	Figure 5	2
Receiver Input Thresholds to Transmitters Disabled		-0.3		0.3	V	1μA supply current, Figure 5	2
INVALID Output Voltage Low				0.4	V	IOUT = 1.6mA	2
Receiver Threshold to Transmitters Enabled (tWU)	tWU			250	µs	Figure 5	2
Receiver Positive or Negative Threshold to INVALID High (tINVH)	tINVH			1	µs	Figure 5	3
Receiver Positive or Negative Threshold to INVALID Low (tINVL)	tINVL			30	µs	Figure 5	3
Input Voltage Range		-25		25	V	Receiver inputs	3
Input Threshold Low		0.6		1.2	V	TA = +25°C; VCC = 3.3V	3
Input Threshold Low		0.8		1.5	V	TA = +25°C; VCC = 5.0V	3
Input Threshold High		1.5		2.4	V	TA = +25°C; VCC = 3.3V	3
Input Threshold High		1.8		2.4	V	TA = +25°C; VCC = 5.0V	3
Input Hysteresis				0.3	V		3
Input Resistance		3	5	7	kΩ	TA = +25°C	3
Output Voltage Swing		-5	5.4		V	All transmitter outputs loaded with 3kΩ to ground	3
Output Resistance		300		10	Ω	VCC = V+ = V- = 0V, transmitter output = ±2V	3
Output Short-Circuit Current		35		60	mA		3
Output Leakage Current		-25		25	µA	VOUT = ±12V, VCC = 0V or 3.0V to 5.5V, transmitters disabled	3
Maximum Data Rate		120	235		kbps	RL = 3kΩ, CL = 1000pF, one transmitter switching	3
Receiver Propagation Delay tPHL	tPHL			0.3	µs	Receiver input to receiver output, CL = 150pF	3
Receiver Propagation Delay tPLH	tPLH			0.3	µs	Receiver input to receiver output, CL = 150pF	3
Receiver Output Enable Time				200	ns	Normal operation	3
Receiver Output Disable Time				200	ns	Normal operation	3
Transmitter Skew	│tPHL, tPLH│			200	ns	MAX3221/MAX3223	3
Receiver Skew	│tPHL, tPLH│			100	ns	MAX3221/MAX3223	3
Transition-Region Slew Rate		4	8	30	V/µs	VCC = 3.3V, RL = 3kΩ to 7kΩ, TA = +25°C, measured from +3V to -3V or -3V to +3V; CL = 200pF to 2500pF	3
Transition-Region Slew Rate		6		30	V/µs	VCC = 3.3V, RL = 3kΩ to 7kΩ, TA = +25°C, measured from +3V to -3V or -3V to +3V; CL = 200pF to 1000pF	3
Supply Voltage VCC	VCC	3		5.5	V	VCC = +3.0V to +5.5V, C1-C4 = 0.1μF	2
Operating Temperature Range MAX3221C	TA	0		70	°C	MAX32_ C _ (commercial)	2
VCC Supply Voltage (absolute maximum)	VCC	-0.3		6	V		2
V+ Voltage (absolute maximum)	V+	-0.3		7	V	Note 1	2
V- Voltage (absolute maximum)	V-	-7		0.3	V	Note 1	2
V+ + /V-/ (absolute maximum)	V+ + /V-/			13	V	Note 1	2
R_IN Input Voltage (absolute maximum)	R_IN	-25		25	V		2
T_OUT Output Voltage (absolute maximum)	T_OUT	-13.2		13.2	V		2
T_IN, FORCEOFF, FORCEON, EN Input Voltage (absolute maximum)		-0.3		6	V	MAX3223 for EN	2
R_OUT, INVALID Output Voltage (absolute maximum lower bound)		-0.3			V	Upper bound is VCC + 0.3V	2
Storage Temperature Range	TSTG	-65		150	°C		2
Lead Temperature (soldering, 10s)				300	°C	10s	2
Thermal Resistance, junction-to-ambient, 16-pin TSSOP (single layer board)	θJA		106		°C/W	Single layer board, package U16+1	15
Thermal Resistance, junction-to-case, 16-pin TSSOP (single layer board)	θJC		27		°C/W	Single layer board, package U16+1	15
Thermal Resistance, junction-to-ambient, 16-pin TSSOP (multi layer board)	θJA		90		°C/W	Multi layer board, package U16+1	15
Thermal Resistance, junction-to-case, 16-pin TSSOP (multi layer board)	θJC		27		°C/W	Multi layer board, package U16+1	15

CAD (KiCad official)

Symbol: MAX3221CUE+T
Footprint: Package_SO:TSSOP-16_4.4x5mm_P0.65mm
3D model: TSSOP-16 (KiCad packages3D, STEP)
3D model files: max3221cue-t-etched.step / max3221cue-t-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); max3221cue-t.step / max3221cue-t.glb are the bare package body.

Provenance

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

Datasheet: Maxim Integrated datasheet (16 pp, sha256 4b10ea08c7155060, 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

MAX3221CUE+T

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3D Model

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