PS509QEX

Overview

The PS509QEX is a CMOS analog multiplexer manufactured by Diodes Incorporated, housed in a 16-pin QSOP package. It provides four differential channels or two dual single-ended channels. The device supports a supply voltage range of 10 V to 36 V for single-supply operation and ±5 V to ±18 V for dual-supply configurations. Key electrical parameters include an on-resistance maximum of 200 Ω at ±10 V, input leakage current of 1 nA, and charge injection of 2 pC. Operating temperatures span from -40°C to +125°C.

Feature Summary

• Supports differential 4:1 or dual 4:1 single-ended channel configurations
• Compatible with TTL and CMOS logic levels across valid supply ranges
• Features break-before-make switching action to prevent signal shorting
• Rail-to-rail operation capability for wide signal handling

Applications

• Factory automation and industrial process controls
• Programmable Logic Controllers (PLC)
• Analog input modules
• ATE test equipment
• Digital multimeters

Procurement Notes

Verify the specific ordering suffix 'QEX' corresponds to the 16-pin QSOP package and tape/reel delivery format as defined in the manufacturer's documentation. Confirm that the component meets RoHS compliance and halogen-free requirements if environmental standards are mandatory for the assembly process.

Selection Notes

Select this component when differential signal routing or dual single-ended multiplexing is required within a 16-pin footprint. Ensure the application operates within the specified 10 V to 36 V single-supply or ±5 V to ±18 V dual-supply limits. Verify that the 200 Ω on-resistance and 20 pF off-capacitance meet the system's signal integrity and bandwidth requirements.

Part Context

The PS509QEX belongs to the PS508/PS509 family of precision analog multiplexers produced by Diodes Incorporated. While the PS508 variant offers eight single-ended channels, the PS509 variant is designed for differential applications. Both share identical pinouts and control logic, allowing for flexible design choices based on channel configuration needs.

Replacement Considerations

The PS508QEX serves as a functional substitute if single-ended 8-channel multiplexing is acceptable instead of differential 4-channel operation. Other packages such as TSSOP (LEX) or SOIC (WEX) offer equivalent electrical performance but require physical footprint adjustments on the PCB layout.

FAQ

Can the PS509 operate with unsymmetric power supplies?

Yes, the datasheet confirms compatibility with unsymmetric supplies, such as VDD = 12V and VSS = –5V, provided the total supply voltage remains within the 10 V to 36 V range.

What is the maximum on-resistance specified for the PS509?

The maximum on-resistance is 200 Ω when operating with a dual supply of ±10 V and a channel current of 1 mA.

How does the EN pin function affect the switch state?

The EN pin is an active-high digital input. When low, all switches are turned off. When high, the address inputs (A0, A1) determine which specific channel pair is activated.