MAX3243EUU - 3V to 5.5V RS-232 Transceiver | Analog Devices
MPN: MAX3243EUU ✓ ActiveMAX3243EUU Overview
An RS-232 transceiver is a bidirectional interface IC that converts logic-level UART signals into RS-232 line levels and converts received line-level signals back into CMOS-compatible digital signals. The MAX3243 combines multiple drivers and receivers with charge-pump circuitry for ±RS-232 voltage generation, reducing the external component count compared with discrete implementations. In the MAX3243EUU, this integration supports a low-voltage system architecture without requiring a separate 5V-only transceiver.
Key electrical features include a 3V to 5.5V operating supply range, multichannel driver and receiver support, and operation up to 250 kbps. The Analog Devices product page identifies the MAX3243 as a production device with AutoShutdown capability, while the TI product listing describes the family as a 3V to 5.5V multichannel 250 kbps RS-232 line driver and receiver with plus-or-minus 15 kV ESD protection.
The MAX3243EUU is supplied in a 28-pin small-outline package identified by distributor listings as TSSOP-28. It is appropriate for UART bridges, USB-to-serial adapters, embedded control boards, test equipment, and industrial serial controllers. Its low-voltage operation allows direct use with 3.3V microcontrollers, provided the logic levels and supply arrangement are verified against the device data sheet.
Designers should confirm the exact package pinout, exposed-pad requirements, charge-pump capacitor values, and RS-232 line-driver loading limits before layout release. Decoupling capacitors should be placed close to the supply and ground pins, while the auto-shutdown and enable functions should be checked for compatibility with the host system's power-management sequence.
This page combines the verified manufacturer and distributor references, pricing information available as of 2026-10-30, package information, and practical design guidance for engineers evaluating the MAX3243EUU in low-voltage serial-interface designs.
Drop-in alternatives for MAX3243EUU — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
MAX3243CPA
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX3243EPA
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX3243ESA
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX3243CSA
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX3243EEAE
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX3243EUU Specifications
| Device Type | RS-232 line driver/receiver transceiver |
| Number of Drivers | 3 |
| Number of Receivers | 3 |
| Supply Voltage Range | 3.0 V to 5.5 V |
| Maximum Data Rate | 250 kbps |
| ESD Protection | ±15 kV |
| AutoShutdown | Yes |
| Operating Temperature | 0 °C to +70 °C |
| Package | TSSOP-28 |
| Mounting Type | Surface mount |
| Logic Compatibility | 3.3 V and 5 V CMOS interface |
| Transceiver Channels | 3 driver/receiver channels |
| RoHS Status | Compliant |
MAX3243EUU tssop-28 Pin Configuration Guide
Pin configuration for MAX3243EUU (tssop-28 package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for MAX3243EUU.
Refer to the datasheet for full pin configuration.
Typical Applications
MAX3243EUU is suitable for 6 applications: 3.3V Embedded UART Interface, USB-to-Serial Adapter, Industrial Serial Control, Data Acquisition Equipment, Instrument and Test Console, Battery-Powered Portable Equipment.
3.3V Embedded UART Interface
The MAX3243EUU fits a 3.3V embedded controller because its verified 3.0V to 5.5V supply range operates directly from a 3.3V rail, while the internal charge-pump circuitry generates the RS-232 line voltages. It is useful when a legacy DB9 or RJ45-style RS-232 port must be added to an industrial controller, data logger, or service console. Place the required charge-pump and bypass capacitors close to the device and route driver outputs away from sensitive logic. The 250 kbps capability supports UART traffic well above common 115200-baud console rates, while the ±15 kV ESD rating helps protect a connector exposed to user-accessible cabling.
Recommended
USB-to-Serial Adapter
MAX3243EUU can provide the host-side RS-232 level conversion in a USB-to-serial adapter that accepts 3.3V or 5V UART signaling. Its three driver and three receiver channels allow several RS-232 ports to share one transceiver, reducing board area when an adapter exposes multiple connectors. The AutoShutdown feature is valuable in portable adapters because the interface can reduce consumption when the USB link is inactive, subject to the host-control implementation. Cable routing and connector grounding are important because long external cables can introduce transients and ground-potential differences that are not solved solely by the integrated ESD protection.
Recommended
Industrial Serial Control
The MAX3243EUU is appropriate for industrial control boards that need an RS-232 service port alongside a modern microcontroller or processor. Its 0 °C to +70 °C verified operating range supports commercial-temperature equipment, and the 250 kbps maximum data rate covers high-speed configuration links and legacy peripheral communication. Three transmit and three receive channels allow multiple point-to-point ports on one board. Designers should verify the actual RS-232 load on each driver, provide adequate chassis and signal grounding, and confirm whether the industrial system requires a wider temperature grade than the listed MAX3243EUU.
Recommended
Data Acquisition Equipment
Data acquisition instruments often need a reliable service and configuration port rather than a high-speed differential interface. MAX3243EUU provides a compact RS-232 interface with three drivers and three receivers, making it possible to expose several instrument-control channels without separate transceiver packages. The 3V-to-5.5V operating range lets the design share a 3.3V or 5V rail with the measurement electronics. Keep the RS-232 traces away from analog inputs and reference nodes, use a solid ground strategy, and confirm the transceiver's shutdown behavior so unused ports do not increase the instrument's standby consumption.
Recommended
Instrument and Test Console
MAX3243EUU is well suited to bench instruments and programming consoles that communicate over RS-232 from a legacy host. The 250 kbps rating provides margin for typical 9600-baud to 115200-baud links, and AutoShutdown can reduce power consumption during idle periods. The TSSOP-28 package supports compact front-panel and single-board designs. Because RS-232 is an unbalanced, single-ended interface, keep cable routing short where possible, use proper connector shielding, and ensure that the logic ground and chassis-ground strategy matches the equipment architecture. The manufacturer data sheet remains the source for charge-pump capacitor values and shutdown timing.
Recommended
Battery-Powered Portable Equipment
The MAX3243EUU can serve as the RS-232 interface in portable measurement or diagnostic equipment powered from a 3.3V battery-derived rail. Its 3.0V minimum supply supports low-voltage designs, while AutoShutdown provides a path to reduce consumption when the serial port is not needed. The integrated ±15 kV ESD protection is valuable for a connector exposed to user cables, although it does not replace correct grounding or surge-protection design. Validate the shutdown current, wake-up behavior, and supply ramp timing in the finished system, and use the manufacturer's reference layout for charge-pump and bypass capacitors.
Recommended
Recommended Products Summary
Engineering reference data for MAX3243EUU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX3243CPA | MAX3243EPA | MAX3243ESA | MAX3243CSA | MAX3243EEAE |
|---|---|---|---|---|---|---|
| Package | TSSOP-28 | TSSOP-28 | TSSOP-28 | TSSOP-28 | TSSOP-28 | TSSOP-28 |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Supply Voltage Range | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Maximum Data Rate | 250 kbps | 250 kbps family rating | 250 kbps family rating | 250 kbps family rating | 250 kbps family rating | 250 kbps family rating |
| ESD Protection | ±15 kV | ±15 kV family rating | ±15 kV family rating | ±15 kV family rating | ±15 kV family rating | ±15 kV family rating |
| Drivers | 3 | 3 | 3 | 3 | 3 | 3 |
| Receivers | 3 | 3 | 3 | 3 | 3 | 3 |
| AutoShutdown | Yes | Yes, MAX3243 family feature | Yes, MAX3243 family feature | Yes, MAX3243 family feature | Yes, MAX3243 family feature | Yes, MAX3243 family feature |
Key Differentiators
- Single-chip integration for three RS-232 channels (vs MAX232DR)
- Lower-voltage operation with integrated shutdown control (vs MAX3243CPA)
- Verified production family with documented protection feature (vs MAX3243EPA)
Design Notes
Place the MAX3243 charge-pump capacitors and local bypass capacitors directly adjacent to their associated pins, following the Analog Devices reference layout. Keep the RS-232 driver traces short and keep them away from receiver inputs, analog nodes, and clock lines. Use a continuous ground reference under the device where the TSSOP-28 footprint permits, and verify the exposed thermal and electrical requirements against the package drawing before release.
Do not treat AutoShutdown as a substitute for a power-management design review. Confirm the ENABLE or shutdown-control logic, supply ramp order, and wake-up time in the final system. Also verify the maximum RS-232 driver load and cable length. The verified data confirms the 3.0V to 5.5V supply, 250 kbps rate, and ±15 kV ESD rating, but connector grounding and external transient protection remain system-level responsibilities.
The verified distributor listing identifies the MAX3243EUU as a 0 °C to +70 °C TSSOP-28 device, but the manufacturer order codes must still be checked for exact package and temperature variants. Before substituting a family member, compare the suffix-specific ordering information, pin names, electrical limits, and package drawing. A family-level functional match is not sufficient evidence of a production drop-in replacement.
Compliance Information
RoHS compliance is reported by the verified JLCPCB listing. REACH, lead-free, halogen-free, conflict-minerals, and AEC-Q100 status were not explicitly provided in the verified data; use the current Analog Devices product documentation and quality declarations for formal certification review.
