LT1328CMS8#PBF

Analog Devices LT1328CMS8#PBF IrDA Photodiode Receiver in MSOP-8

The Analog Devices LT1328CMS8#PBF is a dedicated photodiode receiver IC engineered to support IrDA-compatible infrared data links. Originating from the Linear Technology lineage (now part of Analog Devices), the LT1328 integrates a low-noise transimpedance front end and on-chip signal conditioning to convert photodiode current into a clean digital output suitable for IrDA physical-layer interfaces. Packaged in a compact 8-lead MSOP (MSOP-8, MS8), it is optimized for space-constrained portable devices and peripheral products that require reliable, standards-based infrared communication.

This article distills what you need to know to evaluate, design-in, and source the LT1328CMS8#PBF efficiently—without overpromising or relying on unverified parameters. Where specific numeric limits are not available in the provided data, those items are called out explicitly so you can consult the official datasheet.

Why consider the LT1328CMS8#PBF for your design?

• IrDA-ready receiver path: The LT1328CMS8#PBF is tailored for IrDA-compatible links, translating photodiode current into a digital signal for downstream logic or IrDA PHYs.
• Integrated analog front end: The device integrates a transimpedance amplifier (TIA) and signal conditioning, reducing external component count versus discrete designs.
• Compact footprint: The 8-lead MSOP package fits tight layouts commonly found in laptops, notebooks, PDAs, printers, docking stations, and portable add-ons.
• Proven vendor heritage: As a Linear Technology design under the Analog Devices umbrella, the part benefits from a long track record of low-noise analog design and robust documentation.
• Pb-free/RoHS option: The #PBF suffix indicates a RoHS-compliant, lead-free variant to meet current environmental requirements.

Spec summary and ordering details

• MPN: LT1328CMS8#PBF
• Manufacturer/Brand: Analog Devices (Linear Technology)
• Function: IrDA photodiode receiver IC
• Architecture: Analog front end with integrated transimpedance stage and signal conditioning
• Output: Digital-compatible output intended for IrDA physical-layer interfacing (see datasheet for exact I/O type and logic levels)
• Package / Case: 8-Lead MSOP (MSOP-8, MS8)
• Mounting Type: Surface Mount
• Pin Count: 8
• Packaging: Tube
• RoHS / Environmental: RoHS Compliant (Pb-free #PBF)
• Lifecycle Status: Not specified in the provided data (verify on the Analog Devices product page)
• Electrical limits (supply range, input sensitivity, timing, data-rate class): Not specified in the provided data; consult the datasheet

If your sourcing workflow requires alternates, note that no drop-in replacements are listed in the provided data. Always confirm pin-compatibility and performance before substituting.

What the LT1328 does in an IrDA link

Infrared Data Association (IrDA) links rely on a short-range, line-of-sight IR light path between a transmitter (IR LED) and a receiver (photodiode + receiver IC). The LT1328 sits directly after the photodiode. Its transimpedance amplifier converts the diode’s tiny photocurrent into a voltage, while on-chip signal conditioning shapes and filters the waveform to present a clean digital output to the IrDA physical layer or a host controller.

Engineering value comes from the integration: designing a discrete TIA plus filtering that meets IrDA timing and noise requirements can be time-consuming and layout-sensitive. The LT1328CMS8#PBF provides a known-good analog front end in a small package, shortening design time and reducing risk.

Note on IrDA speed tiers: IrDA historically spans multiple data-rate classes (e.g., SIR, MIR, FIR/VFIR). The specific supported rate class for LT1328 is not included in the provided data—verify required speed compliance in the official datasheet before committing to a design.

Typical applications

• IrDA-compatible infrared data ports in:
• Portable devices and accessories
• Laptops, notebooks, and PDAs
• Printers and docking stations
• Legacy and maintenance equipment that must interoperate with existing IR data ports
• General-purpose photodiode receiver front ends where an IrDA-oriented digital output is desirable

Design-in guidance

While the LT1328CMS8#PBF reduces external component count, success still depends on good system design. The following best practices are general to photodiode receiver ICs and can help you achieve robust performance. For any exact values or pin-specific behavior, consult the LT1328 datasheet.

• Photodiode selection and placement

• Choose a photodiode with an IR-optimized spectral response and, if possible, an integrated IR filter window to reduce visible-light interference.

• Minimize stray capacitance at the photodiode node; extra capacitance can slow edges and degrade sensitivity.

• Keep the photodiode leads short and route them away from high-speed digital traces and clocks to reduce coupling.

• Layout for low noise

• Provide a quiet analog ground reference for the receiver front end; use a solid ground plane and star ground practices where helpful.

• Place the LT1328 and the photodiode close together to minimize loop area and interference pickup.

• Shield or mechanically baffle the photodiode against ambient light sources (fluorescent lighting, sunlight) to avoid saturating the receiver.

• Power integrity and decoupling

• Bypass supply pins with low-ESR capacitors placed as close as possible to the LT1328 supply pins.

• Consider a local ferrite bead and RC filtering if the supply rail is noisy, especially in systems with RF transmitters or switching regulators nearby.

• Output interface considerations

• The LT1328 provides a digital-compatible output. Confirm the logic topology, voltage levels, and any pull-up/pull-down requirements in the datasheet before interfacing to a microcontroller or IrDA PHY.

• If the host device employs aggressive sleep states or variable I/O voltage domains, ensure level compatibility and define a safe reset/initialization sequence.

• EMC/ESD awareness

• Infrared ports are often user-accessible. Implement enclosure design and board-level protection per system-level standards. Check the datasheet and application notes for recommended protection components if applicable.

• Optical alignment

• For maximum range and reliability, align the photodiode field-of-view with the expected transmitter position and consider optical windows or light pipes that preserve IR transmission while blocking visible light.

Specifications at a glance

Only specifications provided by the source data are listed here. For parameters not shown, refer to the official Analog Devices documentation.

• Brand / Manufacturer: Analog Devices (Linear Technology)
• MPN: LT1328CMS8#PBF
• Category: Infrared Receiver ICs / Photodiode Receivers
• Function: IrDA photodiode receiver
• Package: MSOP-8 (8-Lead MSOP)
• Mounting Type: Surface Mount
• Pin Count: 8
• Packaging: Tube
• RoHS Status: RoHS Compliant (Pb-free)
• Lifecycle Status: Not specified in the provided data
• Electrical limits (supply voltage, current consumption, sensitivity, timing, data rate): Not specified in the provided data

Lifecycle, compliance, and supply

• Lifecycle status: Not specified in the provided data. Check the Analog Devices LT1328 product page for the most current lifecycle information, including any product change or discontinuance notices.
• Environmental compliance: RoHS compliant (Pb-free #PBF). If your program requires additional environmental documentation (REACH, halogen content), request compliance certificates from Analog Devices or authorized distributors.
• Availability: Build-to-order; distributor stock may vary. Lead times can fluctuate with demand cycles for maintenance and legacy products—early engagement with distributors is recommended.

Tip for buyers and sourcing managers: Confirm the exact ordering code LT1328CMS8#PBF when placing POs to ensure the Pb-free variant ships. If your corporate AVL or ERP lists legacy Linear Technology numbers, align these with Analog Devices’ current ordering nomenclature.

Practical selection checklist

Use this quick checklist as you qualify the LT1328CMS8#PBF in your design or as a service replacement:

• Interface and protocol

• Your system requires an IrDA-compatible receive path.

• The expected data-rate tier is supported by the LT1328 (verify in the datasheet).

• Electrical and mechanical fit

• MSOP-8 footprint fits your PCB constraints and assembly process.

• Output logic characteristics are compatible with your host device I/O.

• Power rail availability matches the LT1328’s required supply range (verify in datasheet).

• Environmental and compliance

• RoHS compliance is required and satisfied by the #PBF variant.

• Operating temperature and environmental limits meet your application needs (confirm in datasheet if not already validated).

• Supply chain

• Availability aligns with your build plan; consider safety stock if lifecycle status is uncertain.

Applications in context

Engineers often encounter the LT1328CMS8#PBF in two scenarios:

1) New designs that must remain compatible with established IrDA equipment in installed fleets. For example, diagnostic tools, configuration dongles, or service interfaces where IR remains practical due to electrical isolation or EMI considerations.

2) Sustaining and service builds of mature products. The MSOP-8 package and integrated front end make the LT1328 a straightforward replacement or spare, reducing redesign risk when the rest of the system is fixed.

In both cases, the LT1328 simplifies the receive path by integrating the sensitive analog TIA with filtering, helping you achieve predictable results without extensive analog tuning.

Compliance and quality

• RoHS: Pb-free compliant per the #PBF suffix.
• Additional compliance: Not specified in the provided data. If your program requires conformance to specific safety, EMC, or reliability standards, verify with Analog Devices and consult any available application notes or qualification summaries.

Sourcing notes and purchasing tips

• Orderable part: LT1328CMS8#PBF (Pb-free, MSOP-8, tube packaging). Confirm suffixes for packing format if you require tape-and-reel; the provided data lists tube packaging only.
• Approved alternates: None provided. If evaluating alternates, compare:
• Package and pinout compatibility
• Receiver sensitivity and noise performance
• Supported IrDA rate class and timing characteristics
• Output logic type and supply voltage compatibility
• Counterfeit avoidance: Purchase from Analog Devices’ authorized distributors. Match labeling and suffixes (CMS8, #PBF) to your AVL and documentation.

Frequently asked questions (FAQs)

• What is the LT1328CMS8#PBF used for?

• It is an IrDA photodiode receiver IC that converts photodiode current into a conditioned digital output for IrDA physical-layer interfaces.

• What package does the LT1328CMS8#PBF use?

• MSOP-8 (8-lead MSOP) with surface-mount mounting.

• Is the LT1328CMS8#PBF RoHS compliant?

• Yes. The #PBF suffix denotes a Pb-free, RoHS-compliant variant.

• What are the supported IrDA data rates?

• The provided data does not specify speed class. Consult the LT1328 datasheet to confirm compatibility with your required IrDA tier.

• What are the supply voltage and current consumption?

• Not specified in the provided data. Refer to the datasheet for electrical limits and typical operating currents.

• Does the LT1328 provide a digital output?

• Yes, it provides a digital-compatible output intended for IrDA PHY interfacing. Confirm logic type and voltage levels in the datasheet.

• Are there drop-in replacements?

• No approved alternates are listed in the provided data. Evaluate potential substitutes carefully for pinout and performance equivalence.

Resources

• Product page and datasheet: https://www.analog.com/en/products/lt1328.html

If you need parameter confirmation not listed above—such as exact supply range, sensitivity, data-rate compliance, or timing characteristics—refer to the Analog Devices documentation. This will ensure your design meets performance targets without assumptions.

Summary

The Analog Devices LT1328CMS8#PBF is a focused solution for IrDA receiver designs, combining a transimpedance amplifier with on-chip conditioning to deliver a clean, digital-compatible output in a compact MSOP-8 package. Its Pb-free, RoHS-compliant build and space-efficient form factor make it a natural fit for portable devices, printers, docking stations, and maintenance equipment that rely on IrDA communications. While several key electrical limits are not included in the provided data, the official datasheet will supply the necessary detail to finalize your design. For sourcing, specify LT1328CMS8#PBF to obtain the lead-free MSOP-8 variant and consult authorized channels for current availability and lifecycle status.