ST232BDR from UMW, 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 voltage-doubler charge-pump capacitor C1. Connect a 0.1 µF capacitor between C1+ (pin 1) and C1- (pin 3).
2	V+	power_out	Regulated +2·VCC (approx. +10 V) output generated by the internal charge pump. Bypass to GND with a 0.1 µF capacitor.
3	C1-	passive	Negative terminal of the voltage-doubler charge-pump capacitor C1. Paired with C1+ (pin 1) via a 0.1 µF capacitor.
4	C2+	passive	Positive terminal of the inverter charge-pump capacitor C2. Connect a 0.1 µF capacitor between C2+ (pin 4) and C2- (pin 5).
5	C2-	passive	Negative terminal of the inverter charge-pump capacitor C2. Paired with C2+ (pin 4) via a 0.1 µF capacitor.
6	V-	power_out	Regulated -2·VCC (approx. -10 V) output generated by the internal inverting charge pump. Bypass to GND with a 0.1 µF capacitor.
7	T2OUT	output	RS-232 driver 2 output. Swings between V+ and V- (typical ±5 V into a 3 kΩ load), inverted from the T2IN TTL/CMOS input.
8	R2IN	input	RS-232 receiver 2 input. Accepts EIA/TIA-232E line levels (±30 V absolute max) with an internal 3-7 kΩ pull-down and hysteresis (VIL≈0.8 V, VIH≈2.4 V).
9	R2OUT	output	TTL/CMOS receiver 2 output (inverted from R2IN). Drives VOL ≤ 0.4 V at 3.2 mA and VOH ≥ 3.5 V at -1 mA.
10	T2IN	input	TTL/CMOS driver 2 input. High-impedance CMOS input (VIL ≤ 0.8 V, VIH ≥ 2 V) whose logic level is inverted and level-shifted to the T2OUT RS-232 line driver.
11	T1IN	input	TTL/CMOS driver 1 input. High-impedance CMOS input (VIL ≤ 0.8 V, VIH ≥ 2 V) whose logic level is inverted and level-shifted to the T1OUT RS-232 line driver.
12	R1OUT	output	TTL/CMOS receiver 1 output (inverted from R1IN). Drives VOL ≤ 0.4 V at 3.2 mA and VOH ≥ 3.5 V at -1 mA.
13	R1IN	input	RS-232 receiver 1 input. Accepts EIA/TIA-232E line levels (±30 V absolute max) with an internal 3-7 kΩ pull-down and hysteresis (VIL≈0.8 V, VIH≈2.4 V).
14	T1OUT	output	RS-232 driver 1 output. Swings between V+ and V- (typical ±5 V into a 3 kΩ load), inverted from the T1IN TTL/CMOS input.
15	GND	power_in	Device ground reference and return path for the charge-pump bypass capacitors on V+ and V-.
16	VCC	power_in	Positive supply input, +4.5 V to +5.5 V. Typical quiescent supply current ICC ≤ 10 mA (no load, 25 °C). Bypass to GND with a 0.1 µF capacitor.

Key specifications

Parameter	Value
Manufacturer	UMW
Package	SOP-16
Category	Comm/UART
Pins	16

Ordering variants

Same part, different packaging or reel option.

ST232BDR
ST232CDR

CAD (KiCad official)

Symbol: ST232BDR
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOP-16 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`st232bdr.step`	217 KB	You want the bare part, or you mark your own boards.
`st232bdr-etched.step`	2.4 MB	You want the part with `ST232BDR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 601 faces against 267 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: UMW datasheet (10 pp, sha256 2e25f6be595237d6, 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