TMUX1237

SEL

S1

D

S2

18

TMUX1237

SCDS424A – DECEMBER 2019 – REVISED MARCH 2020

www.ti.com

Product Folder Links: TMUX1237

Submit Documentation Feedback

Copyright © 2019–2020, Texas Instruments Incorporated

8 Detailed Description

8.1 Overview

The TMUX1237 is an 2:1 (SPDT), 1-channel switch where the input is controlled with a single select (SEL)

control pin.

8.2 Functional Block Diagram

Figure 16. TMUX1237 Functional Block Diagram

8.3 Feature Description

8.3.1 Bidirectional Operation

The TMUX1237 conducts equally well from source (Sx) to drain (D) or from drain (D) to source (Sx). The device

has very similar characteristics in both directions and supports both analog and digital signals.

8.3.2 Rail to Rail Operation

The valid signal path input/output voltage for TMUX1237 ranges from GND to VDD.

8.3.3 1.8 V Logic Compatible Inputs

The TMUX1237 has 1.8-V logic compatible control for the logic control input (SEL). The logic input threshold

scales with supply but still provides 1.8-V logic control when operating at 5.5 V supply voltage. 1.8-V logic level

inputs allow the TMUX1237 to interface with processors that have lower logic I/O rails and eliminates the need

for an external translator, which saves both space and BOM cost. For more information on 1.8 V logic

implementations refer to Simplifying Design with 1.8 V logic Muxes and Switches

8.3.4 Fail-Safe Logic

The TMUX1237 supports Fail-Safe Logic on the control input pin (SEL) allowing for operation up to 5.5 V,

regardless of the state of the supply pin. This feature allows voltages on the control pin to be applied before the

supply pin, protecting the device from potential damage. Fail-Safe Logic minimizes system complexity by

removing the need for power supply sequencing on the logic control pins. For example, the Fail-Safe Logic

feature allows the select pin of the TMUX1237 to be ramped to 5.5 V while VDD = 0 V. Additionally, the feature

enables operation of the TMUX1237 with VDD = 1.2 V while allowing the select pin to interface with a logic level

of another device up to 5.5 V.