SN3257QPWRQ1 from Texas Instruments, in a TSSOP-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	SEL	input	Select pin: controls state of switches (routes SxA or SxB to Dx). 1.8 V-compatible logic input with internal 6 MΩ pull-down to GND (VIH ≥ 1.2 V, VIL ≤ 0.45 V).
2	S1A	bidirectional	Source pin 1A of channel 1. Analog/digital I/O routed to D1 when SEL selects the A path. RON ≈ 5 Ω, signals 0 V to 2×VDD (max 5.5 V).
3	S1B	bidirectional	Source pin 1B of channel 1. Analog/digital I/O routed to D1 when SEL selects the B path. RON ≈ 5 Ω, signals 0 V to 2×VDD.
4	D1	bidirectional	Drain pin 1 (common) of channel 1. Connects to either S1A or S1B based on SEL. Bidirectional analog switch path.
5	S2A	bidirectional	Source pin 2A of channel 2. Routed to D2 when SEL selects the A path.
6	S2B	bidirectional	Source pin 2B of channel 2. Routed to D2 when SEL selects the B path.
7	D2	bidirectional	Drain pin 2 (common) of channel 2. Connects to either S2A or S2B based on SEL.
8	GND	power_in	Ground (0 V) reference.
9	D3	bidirectional	Drain pin 3 (common) of channel 3. Connects to either S3A or S3B based on SEL.
10	S3B	bidirectional	Source pin 3B of channel 3. Routed to D3 when SEL selects the B path.
11	S3A	bidirectional	Source pin 3A of channel 3. Routed to D3 when SEL selects the A path.
12	D4	bidirectional	Drain pin 4 (common) of channel 4. Connects to either S4A or S4B based on SEL.
13	S4B	bidirectional	Source pin 4B of channel 4. Routed to D4 when SEL selects the B path.
14	S4A	bidirectional	Source pin 4A of channel 4. Routed to D4 when SEL selects the A path.
15	EN	input	Active-low enable (EN). When high, all switches are turned off (Hi-Z); when low, SEL controls the signal path selection. Internal 6 MΩ pull-down to GND.
16	VDD	power_in	Positive power supply (1.5 V to 5.5 V). Connect a 0.1 µF to 10 µF decoupling capacitor between VDD and GND for reliable operation.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	TSSOP-16
Category	Interface
Pins	16

Ordering variants

Same part, different packaging or reel option.

SN3257QPWRQ1
SN3257QPWRQ1DYY

CAD (KiCad official)

Symbol: SN3257QPWRQ1
Footprint: Package_SO:TSSOP-16_4.4x5mm_P0.65mm
3D model: TSSOP-16 (KiCad packages3D, STEP)

Provenance

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

Datasheet: Texas Instruments datasheet (38 pp, sha256 2bd0cef536bfca7d, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
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