A dual RS-232 transceiver in SOIC-16, the low-voltage successor to the MAX232. It converts between a microcontroller's logic-level UART and the plus/minus RS-232 line levels, generating those swings from a single 3 to 5.5 V rail with an on-chip charge pump and four external capacitors, so it bridges a 3.3 V MCU to a PC serial port without a negative supply. It carries two transmit drivers and two receive buffers, enough for TX/RX plus one handshake pair. Pin-compatible with the MAX232 and good to 250 kbit/s.

Pinout

Pin	Name	Type	Function
1	C1+	passive	Positive lead of charge-pump capacitor C1 (typ. 0.1 µF at VCC = 3.3 V, or 0.047 µF at VCC = 5 V). Connect between C1+ and C1- as part of the charge-pump network.
2	V+	power_out	Positive charge-pump output for storage capacitor only. Nominally VCC-referenced positive rail generated by the internal charge pump (approx. +5.5 V). Connect a 0.1 µF (or 0.33 µF at 5 V) storage capacitor from V+ to GND.
3	C1-	passive	Negative lead of charge-pump capacitor C1. Connect between C1+ and C1- as part of the charge-pump network.
4	C2+	passive	Positive lead of charge-pump capacitor C2 (typ. 0.1 µF at 3.3 V, or 0.33 µF at 5 V). Connect between C2+ and C2- as part of the inverter charge-pump network.
5	C2-	passive	Negative lead of charge-pump capacitor C2. Connect between C2+ and C2- as part of the inverter charge-pump network.
6	V-	power_out	Negative charge-pump output for storage capacitor only. Inverted negative rail (approx. -5.5 V) generated by the internal charge pump. Connect a 0.1 µF (or 0.33 µF at 5 V) storage capacitor from V- to GND.
7	DOUT2	output	RS-232 line data output for channel 2 (to remote RS-232 system). Driver output swings between V+ and V- (typ. ±5.4 V), short-circuit protected to ground (Ios ~ ±35 mA).
8	RIN2	input	RS-232 line data input for channel 2 (from remote RS-232 system). Includes internal 3-7 kΩ RS-232 load; input voltage range ±25 V. Thresholds: VIT+ typ 1.5-1.8 V, VIT- typ 0.6-0.8 V.
9	ROUT2	output	Logic-level data output for channel 2 (to UART). CMOS-level output referenced to VCC; VOH ≥ VCC-0.6 V at IOH = -1 mA, VOL ≤ 0.4 V at IOL = 1.6 mA. Inverted from RIN2; open RIN gives high ROUT.
10	DIN2	input	Logic-level data input for channel 2 (from UART). Accepts 3-V or 5-V logic (VIH ≥ 2 V at VCC = 3.3 V, ≥ 2.4 V at VCC = 5 V; VIL ≤ 0.8 V). Input range 0 to 5.5 V; must be driven valid high or low.
11	DIN1	input	Logic-level data input for channel 1 (from UART). Accepts 3-V or 5-V logic (VIH ≥ 2 V at VCC = 3.3 V, ≥ 2.4 V at VCC = 5 V; VIL ≤ 0.8 V). Input range 0 to 5.5 V; must be driven valid high or low.
12	ROUT1	output	Logic-level data output for channel 1 (to UART). CMOS-level output referenced to VCC; VOH ≥ VCC-0.6 V at IOH = -1 mA, VOL ≤ 0.4 V at IOL = 1.6 mA. Inverted from RIN1; open RIN gives high ROUT.
13	RIN1	input	RS-232 line data input for channel 1 (from remote RS-232 system). Includes internal 3-7 kΩ RS-232 load; input voltage range ±25 V. Thresholds: VIT+ typ 1.5-1.8 V, VIT- typ 0.6-0.8 V.
14	DOUT1	output	RS-232 line data output for channel 1 (to remote RS-232 system). Driver output swings between V+ and V- (typ. ±5.4 V), short-circuit protected to ground (Ios ~ ±35 mA).
15	GND	power_in	Device ground reference. All voltages are with respect to this network GND.
16	VCC	power_in	Supply voltage; connect to external 3 V to 5.5 V power supply (recommended 3.0-3.6 V or 4.5-5.5 V). ICC typical 0.3 mA, max 1 mA at no load. Bypass with 0.1 µF.

Key specifications

Parameter	Value
Type	Dual RS-232 transceiver
Drivers / receivers	2 / 2
Supply voltage	3-5.5 V (single)
Level generation	on-chip charge pump (4 caps)
Data rate	up to 250 kbit/s
Compatibility	pin-identical to MAX232
ESD	±15 kV (line pins)
Package	SOIC-16

Ordering variants

Same part, different packaging or reel option.

MAX3232CDR (SOIC-16)
MAX3232IDR (SOIC-16, industrial)

CAD (KiCad official)

Symbol: Interface_UART:MAX3232
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOIC-16 (KiCad packages3D)

Provenance

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

Datasheet: Texas Instruments datasheet (30 pp, sha256 13b1834e8de7c628, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF