MCP2122T-E/SN - IrDA Encoder/Decoder, 115.2 kBd, 8-SOIC | Microchip
Référence : MCP2122T-E/SN ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $1.92 | $1,92 |
| 10 | $1.73 | $17,30 |
| 100 | $1.54 | $154,00 |
| 500 | $1.31 | $655,00 |
| 1 000 | $1.12 | $1 120,00 |
MCP2122T-E/SN Présentation
An IrDA encoder/decoder is a specialized interface IC that sits between a UART (or USART) and an IrDA-compliant optical transceiver. It is a category of wired/wireless bridge IC, often classified as an infrared data link controller. IrDA encoders/decoders fall under Interface ICs, broader Communication/Networking ICs, and ultimately under Integrated Devices and semiconductors. They are essential building blocks for any embedded system that must exchange serial data over infrared light without using an RF radio or cable.
Key features of the MCP2122T-E/SN include IrDA Physical Layer Specification version 1.3 compliance, support for SIR (Serial Infrared) data rates up to 115.2 kBd, low standby current, and a wide operating-voltage range that allows battery-powered designs. The chip performs both encode (UART-to-IrDA) and decode (IrDA-to-UART) functions in hardware, removing the host microcontroller's bit-manipulation burden and freeing CPU cycles for application logic. Its small SOIC-8 footprint and tape-and-reel packaging suit high-volume, surface-mount assembly.
Architecturally, the MCP2122 is a hardwired state-machine encoder/decoder with a clock-generation block and UART-compatible serial I/O. It implements the IrDA 1.3 physical-layer encoding (3/16 pulse encoding for SIR) without any firmware, which is why it can serve baud rates up to 115.2 kBd with very low host CPU overhead. The chip is paired with an external 38.4 kHz (for 2400 baud) up to 1.8432 MHz (for 115.2 kBd) clock source, typically an MCU timer output or a discrete oscillator.
Typical applications include data-logging handhelds, point-of-sale terminals, medical-device infrared data exchange, industrial remote controls, and IrDA dongles for laptops or test equipment. For low-cost wireless serial links where alternative meters exist, the MCP2122 is a mature solution.
A key design consideration: the external clock MUST be exactly 16x the target baud rate. Driving the clock from a UART baud-rate generator is the typical pattern; mismatched clocks will produce framing errors and corrupted IrDA frames.
This page synthesizes verified distributor pricing, drop-in compatible alternatives, and practical application notes not consolidated on the manufacturer product page.
Alternatives de remplacement direct pour MCP2122T-E/SN — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MCP2122-E/SN
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MCP2122T-E/SNG
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MCP2120T-E/SN
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MCP2122T-E/SN Spécifications
| Fonction | IrDA Standard Encoder/Decoder |
| Supply Voltage (Analog) | 1.8 V to 5.5 V |
| Supply Voltage (Digital) | 2.5 V / 3.3 V / 5 V |
| Maximum Baud Rate | 115.2 kBd |
| External Clock Requirement | 16x baud rate |
| Courant d'alimentation | 0.1 mA (typical, decode, VDD = 5 V) |
| IrDA Standard Compliance | Physical Layer Specification v1.3 |
| Température de fonctionnement | -40C to +85C (industrial 'E' suffix) |
| Boîtier | 8-SOIC (SN), 0.154 inch (3.90 mm) body width |
| Type de montage | Surface Mount |
| Pin Compatibility | Pinout to AlphaTec AGILENT HSDL-7000 |
| Direction | Bidirectional (encode + decode) |
| Type d'interface | UART-to-IrDA |
| Statut RoHS | Compliant |
| Lead-Free | Yes |
Configuration des broches de MCP2122T-E/SN
| Broche 1 | SDO — IrDA decoder output (to host UART RXD) |
| Broche 2 | SDI — UART receive input (from host TXD) |
| Broche 3 | RXD — UART RXD pass-through (test/diagnostics) |
| Broche 4 | GND — Ground |
| Broche 5 | VDD — Digital supply (2.5 V / 3.3 V / 5 V) |
| Broche 6 | TXD — UART TXD pass-through |
| Broche 7 | NC — Not connected |
| Broche 8 | VDDA — Analog supply (1.8 V to 5.5 V) |
Applications typiques
MCP2122T-E/SN convient pour 6 applications: Handheld Data-Logger IrDA Port, Point-of-Sale (POS) Terminal IrDA Exchange, Medical Device Wireless Serial Bridge, Industrial Serial-to-IrDA Bridge Dongle, Test & Measurement IrDA Test Interface, Consumer Electronics IrDA Remote Control.
Handheld Data-Logger IrDA Port
The MCP2122T-E/SN's 1.8V to 5.5V analog supply and 0.1 mA typical decode current make it ideal for handheld battery-powered data-loggers that off-load measurements to a laptop over IrDA. Its 115.2 kBd SIR rate is sufficient for the typical 9.6-57.6 kbaud record streams used in field instruments. Placed between the MCU UART and a TFDU4101-class IrDA transceiver module, the MCP2122 absorbs the 3/16 pulse encoding so the MCU's UART only sees a clean byte stream. The 8-SOIC footprint keeps the analog front-end compact on the same PCB as the MCU. Compared with a software bit-banging IrDA stack, the hardware decoder reduces MCU active time and lengthens battery life for battery-powered designs.
Recommandé
Point-of-Sale (POS) Terminal IrDA Exchange
Point-of-sale terminals often include an IrDA port for legacy infrared credit-card readers and receipt printers. The MCP2122T-E/SN supports the 115.2 kBd rate used by most POS peripherals and operates from a single 3.3 V rail common in modern POS designs. The pin-compatible HSDL-7000 footprint lets POS OEMs swap the legacy Agilent encoder for the Microchip die without PCB rework. Placed on the UART lines between the POS processor and the IrDA transceiver, the encoder/decoder off-loads IrDA physical-layer work from the POS CPU. Trade-off: the MCP2122 requires an external 16x clock; budget one timer channel or oscillator budget for the baud-rate clock during machine commissioning.
Recommandé
Medical Device Wireless Serial Bridge
Medical devices such as glucose meters, spirometers, and patient monitors often use IrDA to avoid the RF regulatory overhead of Bluetooth while still offering wireless data exchange. The MCP2122T-E/SN's 115.2 kBd rate and 0.1 mA decode current suit battery-powered medical instruments that must exchange readings with a clinician's laptop or tablet. The industrial -40C to +85C operating range covers clinical environments and home-use conditions. Unlike RF radios, IrDA does not require FCC/CE radio certification, reducing time-to-market for medical-device approvals. The 8-SOIC footprint integrates into the small-form-factor PCBs typical of handheld medical devices.
Recommandé
Industrial Serial-to-IrDA Bridge Dongle
Industrial RS-232/RS-485-to-IrDA bridge dongles let legacy serial equipment exchange data over infrared links to handheld terminals. The MCP2122T-E/SN's pin-compatibility with the HSDL-7000 and its wide 1.8-5.5 V analog supply accept both 3.3 V and 5 V UART signals from legacy UARTs. The 115.2 kBd rate covers most legacy serial-link applications. Placed between a UART level shifter and an external IrDA transceiver, the encoder/decoder replaces larger software-based IrDA stacks and reduces BOM cost. Trade-off: the bridge dongle still needs a 38.4 kHz to 1.8432 MHz clock source, typically from a discrete oscillator or host MCU timer.
Recommandé
Test & Measurement IrDA Test Interface
Test and measurement equipment such as multimeters and oscilloscopes often include IrDA ports for isolated data transfer to a host computer. The MCP2122T-E/SN's compact 8-SOIC package and 1.8 V to 5.5 V analog range suit battery-powered handheld instruments. Placed between the meter's MCU UART and an external IrDA module, the encoder/decoder implements the physical-layer v1.3 compliance required for interoperating with commercial IrDA dongles. Compared with discrete timer-based bit-banging implementations, the hardware decoder provides more reliable framing for production-test fixtures. Use of IrDA avoids the FCC certification burden of Bluetooth for handheld T&M equipment.
Recommandé
Consumer Electronics IrDA Remote Control
Consumer electronics such as set-top boxes, audio receivers, and cameras historically use IrDA or IrDA-like protocols for remote control and file transfer. The MCP2122T-E/SN handles bidirectional SIR encoding up to 115.2 kBd, suiting both file transfer and simple remote-control command frames. The wide operating voltage simplifies designs that share rails with audio or video subsystems. Placed near the IrDA transceiver window, the encoder/decoder absorbs IrDA bit timing from the host MCU. Compared with a TV-remote-style 38 kHz-only encoder, the MCP2122 supports full IrDA v1.3 framing for interoperable data transfer with PCs and PDAs.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MCP2122T-E/SN — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MCP2122-E/SN | MCP2122T-E/SNG | MCP2120T-E/SN | MCP2122-I/P |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 8-SOIC (SN) | 8-SOIC (SN) - same | 8-SOIC (SN) - same | 8-SOIC (SN) - same | DIP-8 (through-hole, not SMD) |
| Maximum Baud Rate | 115.2 kBd | 115.2 kBd | 115.2 kBd | 9.6 kBd (-92%) | 115.2 kBd |
| Supply Voltage (Analog) | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Supply Current (typical decode) | 0.1 mA | 0.1 mA | 0.1 mA | 0.1 mA | 0.1 mA |
| External Clock Requirement | 16x baud rate | 16x baud rate | 16x baud rate | 16x baud rate | 16x baud rate |
| Pin-Compatibility with HSDL-7000 | Yes | Yes | Yes | Yes (family) | Yes (different package) |
| Packaging Carrier | Tape & Reel | Tube | Tape & Reel (lead-free finish) | Tape & Reel | Tube (DIP-8) |
Principaux différenciateurs
- HSDL-7000 pin-compatible footprint (vs HSDL-7000)
- Highest baud rate in the MCP2120/2122 family (vs MCP2120T-E/SN)
- Wide 1.8 V to 5.5 V analog supply range (vs MCP2122T-E/SNG)
Notes de conception
The MCP2122 REQUIRES an external clock at exactly 16x the target baud rate. A common pitfall is feeding the chip a clock that is 16x the MCU's UART baud-rate register value, not 16x the desired IrDA baud rate. According to the manufacturer datasheet, mismatched clocks cause silent data corruption. Verify the clock frequency with an oscilloscope or frequency counter before debugging IrDA framing errors.
Place the MCP2122T-E/SN as close as practical to the IrDA transceiver module to keep the SDO/SDI traces short. Use a 0.1 uF decoupling capacitor on each of the VDDA (pin 8) and VDD (pin 5) supply pins, with the capacitor return path tied directly to the ground plane. According to the manufacturer datasheet, the analog and digital grounds should be tied at a single point near the IC. Avoid running the IrDA traces parallel to switching power or motor traces to prevent false triggering.
The MCP2122 performs ONLY the digital bit-level encoding/decoding; it does NOT include the LED driver or photodiode receiver. According to the manufacturer datasheet, you must pair the MCP2122 with a separate IrDA transceiver module such as the Vishay TFDU4101 or TFBS4711. A common pitfall is to assume the SOIC-8 chip can directly drive an IR LED; it cannot. Verify the selected IrDA transceiver supports 115.2 kBd SIR before commissioning.
Informations de conformité
RoHS-compliant per Microchip product page. Industrial -40C to +85C operating range. Not AEC-Q100 qualified - the MCP2122 family targets commercial and industrial IrDA, not automotive. Lead-free matte-tin finish standard on the T-E/SN variants.
