HGX232ECM from HGSEMI, in a SOP-16. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	C1+	passive	Positive terminal of the external flying capacitor for the positive charge-pump voltage multiplier. Connect a 0.1 uF capacitor between C1+ (pin 1) and C1- (pin 3).
2	V+	power_out	Positive output of the charge-pump voltage multiplier (approximately +10 V from a 5 V VCC). Bypass to VCC with a 0.1 uF capacitor.
3	C1-	passive	Negative terminal of the external flying capacitor for the positive charge-pump voltage multiplier. Pairs with C1+ (pin 1).
4	C2+	passive	Positive terminal of the external flying capacitor for the negative charge-pump voltage multiplier. Connect a 0.1 uF capacitor between C2+ (pin 4) and C2- (pin 5).
5	C2-	passive	Negative terminal of the external flying capacitor for the negative charge-pump voltage multiplier. Pairs with C2+ (pin 4).
6	V-	power_out	Negative output of the charge-pump voltage multiplier (approximately -10 V from a 5 V VCC). Bypass to GND with a 0.1 uF capacitor.
7	T2OUT	output	Transmitter 2 output at RS-232 levels (typically +/-5 V or greater). Drives the far-end RS-232 receiver line.
8	R2IN	input	Receiver 2 input at RS-232 levels (up to +/-30 V). Internally biased with ~5 kOhm input resistance to ground.
9	R2OUT	output	Receiver 2 output at TTL/CMOS levels. Inverted output of the R2IN receiver.
10	T2IN	input	Transmitter 2 input at TTL/CMOS levels. Driven by the host UART TXD line.
11	T1IN	input	Transmitter 1 input at TTL/CMOS levels. Driven by the host UART TXD line.
12	R1OUT	output	Receiver 1 output at TTL/CMOS levels. Inverted output of the R1IN receiver.
13	R1IN	input	Receiver 1 input at RS-232 levels (up to +/-30 V). Internally biased with ~5 kOhm input resistance to ground.
14	T1OUT	output	Transmitter 1 output at RS-232 levels (typically +/-5 V or greater). Drives the far-end RS-232 receiver line.
15	GND	power_in	Ground / common return. All supply and signal returns reference this pin.
16	VCC	power_in	Positive supply input, 4.5 V to 5.5 V recommended (6.0 V absolute maximum). Decouple to GND with a 0.1 uF capacitor.

Key specifications

Parameter	Value
Manufacturer	HGSEMI
Package	SOP-16
Category	Interface
Pins	16

Ordering variants

Same part, different packaging or reel option.

HGX232ECM/TR
HGX232EIM/TR
HGX232ECN
HGX232EIN
HGX232ECMT/TR
HGX232EIMT/TR

CAD (KiCad official)

Symbol: HGX232ECM
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOP-16 (KiCad packages3D, STEP)

Provenance

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

Datasheet: HGSEMI datasheet (11 pp, sha256 10f1bf5b12850453, retrieved 2026-08-17, tier: lcsc)
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