Routes one of eight analog inputs (S1-S8) to a single common pin (D) under a 3-bit address, a modern precision replacement for the classic 4051. It runs on a single 1.8 to 5.5 V rail or a dual supply down to VSS for bipolar signals, with low on-resistance, low leakage, and fast switching that keeps signal error small. An EN pin disconnects all channels. Good for multiplexing sensor and ADC front ends where the older CMOS muxes leak or distort.

Pinout

Pin	Name	Type	Function
1	A0	input	Address line 0. Controls the switch configuration (which Sx channel connects to D) per the truth table. 1.8 V logic compatible; VIH ≥ 1.49 V, VIL ≤ 0.87 V at VDD = 5 V.
2	EN	input	Active-high enable input. When low, all switches are turned off; when high, the A[2:0] address inputs determine which channel is on. Fail-safe logic tolerates control voltages before VDD is applied.
3	VSS	power_in	Negative power supply. Tie to GND for single-supply operation, or to a negative rail for bipolar signal switching.
4	S1	bidirectional	Source pin 1. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
5	S2	bidirectional	Source pin 2. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
6	S3	bidirectional	Source pin 3. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
7	S4	bidirectional	Source pin 4. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
8	D	bidirectional	Common drain pin. Bidirectional analog/digital terminal that connects to the selected Sx source per the A[2:0]/EN inputs. Signal range: GND to VDD.
9	S8	bidirectional	Source pin 8. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
10	S7	bidirectional	Source pin 7. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
11	S6	bidirectional	Source pin 6. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
12	S5	bidirectional	Source pin 5. Bidirectional analog/digital switch terminal; can be input or output. Signal range: GND to VDD; RON ≈ 5 Ω typical at VDD = 5 V.
13	VDD	power_in	Positive power supply, 1.08 V to 5.5 V. Connect a 0.1 µF to 10 µF decoupling capacitor between VDD and GND close to the pin.
14	GND	power_in	Ground (0 V) reference for the device.
15	A2	input	Address line 2. Controls the switch configuration per the truth table. 1.8 V logic compatible.
16	A1	input	Address line 1. Controls the switch configuration per the truth table. 1.8 V logic compatible.

Key specifications

Parameter	Value
Type	8:1 analog multiplexer
Channels	8 (S1-S8) to 1 (D)
Address	3-bit (A0-A2) + EN
Supply	1.8-5.5 V single or +/-2.75 V dual
Leakage	Low (pA range)
Switching	Break-before-make
Package	TSSOP-16

Ordering variants

Same part, different packaging or reel option.

TMUX1208PWR (TSSOP-16)
TMUX1208RSVR (UQFN-16)

CAD (KiCad official)

Symbol: Analog_Switch:TMUX1208PW (KiCad official)
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 (37 pp, sha256 c2683e83f693c8d9, 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