MAX3232IDW - Dual RS-232 Transceiver, 3-5.5V | Texas Instruments
MPN: MAX3232IDW ✓ ActiveMAX3232IDW Overview
An RS-232 transceiver is an interface IC that converts low-voltage CMOS logic signals into RS-232-compatible levels and receives differential bipolar signals back into CMOS logic. Within the interface IC hierarchy, the MAX3232IDW belongs to the RS-232 transceiver family, supports TIA/EIA-232-F and ITU V.28 requirements, and is commonly used to connect 3.3 V or 5 V controllers to legacy serial equipment.
Key features include operation from 3 V to 5.5 V, data rates up to 250 kbit/s, low supply current of 300 µA typical, and compatibility with 5 V logic. The charge-pump design generates the positive and negative voltages required for true RS-232 signaling without an external 12 V supply. Four external 0.1 µF capacitors are required for the charge-pump and voltage-regulation functions.
The device combines two transmit channels with two receive channels in one package. Each driver converts a CMOS logic input into an RS-232 output, while each receiver converts an RS-232 input into a CMOS output. The internal charge pumps support both 3 V and 5 V operation, allowing the same interface design to be used across common embedded and industrial supply levels.
Typical applications include serial port adapters, industrial control equipment, data acquisition systems, point-of-sale terminals, test and measurement instruments, and embedded systems communicating with legacy RS-232 peripherals. The ±15 kV ESD protection improves robustness when cables are connected or disconnected in industrial environments.
For PCB layout, place the four 0.1 µF charge-pump capacitors close to their associated pins and route each RS-232 trace away from sensitive analog or high-speed digital signals. Confirm logic thresholds, connector protection, cable length, and grounding before releasing a design, especially when connecting the interface to exposed external cables.
This page organizes the electrical limits, package information, verified pricing, drop-in alternatives, and application guidance for engineers evaluating the MAX3232IDW in a new or existing RS-232 design.
Drop-in alternatives for MAX3232IDW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MAX3232IDW (same form factor and footprint) — differing in Operating Temperature, Package, ESD Protection, Maximum Data Rate, Number of Drivers.
MAX3232EIDWR
✅ Drop-In📋 Reference alternative (not in catalog)
MAX3232EID
✅ Drop-InContact for price
View Datasheet →MAX3232EWE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX3232IDRE4
✅ Drop-InContact for price
View Datasheet →MAX232IDWR
✅ Drop-In📋 Reference alternative (not in catalog)
MAX3232IDW Specifications
| Device Type | RS-232 line driver/receiver transceiver |
| Number of Drivers | 2 |
| Number of Receivers | 2 |
| Supply Voltage Range | 3 V to 5.5 V |
| Maximum Data Rate | 250 kbit/s |
| Supply Current | 300 µA typical |
| ESD Protection | ±15 kV |
| External Capacitors | 4 x 0.1 µF |
| Logic Compatibility | 5 V logic |
| RS-232 Compliance | TIA/EIA-232-F and ITU V.28 |
| Technology | RS-232 and CMOS |
| Package | 16-pin SOIC (DW), 5.30 mm body width |
| Pin Count | 16 |
| Operating Temperature | 0°C to 70°C |
| Charge-Pump Architecture | Dual charge-pump circuit |
| Power Rail Topology | Dual positive and negative voltage generation |
| Mounting Type | Surface mount |
MAX3232IDW 16-pin soic (dw), 5.30 mm body width Pin Configuration Guide
Pin configuration for MAX3232IDW (16-pin soic (dw), 5.30 mm body width 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 MAX3232IDW.
Refer to the datasheet for full pin configuration.
Typical Applications
MAX3232IDW is suitable for 6 applications: 3.3 V Embedded Serial Port Interface, Industrial Serial Port Adapter, RS-232-to-TTL Serial Adapter, Data Acquisition Equipment, Point-of-Sale Terminal Interface, Test and Measurement Instrument Interface.
3.3 V Embedded Serial Port Interface
The MAX3232IDW is appropriate for a 3.3 V microcontroller that needs an RS-232 port without a 5 V-only interface limitation. Its 3 V to 5.5 V operating range supports the controller supply while the dual charge-pump circuit produces the positive and negative voltages required for RS-232 signaling. The two drivers and two receivers enable a console, configuration port, or data link on one device. Four external 0.1 µF capacitors implement the charge-pump functions, and the 250 kbit/s maximum data rate suits conventional asynchronous serial communication.
Recommended
Industrial Serial Port Adapter
The MAX3232IDW fits industrial adapters that translate controller logic into RS-232 for machinery, instruments, or service equipment. Its ±15 kV ESD protection is valuable when an external cable is connected frequently, although it does not replace a surge-protection network for severe transients. The 0°C to 70°C operating range supports common industrial environments. Place the four 0.1 µF capacitors close to the IC, route protected cable traces away from sensitive circuitry, and verify the grounding strategy at the connector.
Recommended
RS-232-to-TTL Serial Adapter
The MAX3232IDW can implement a compact RS-232-to-TTL adapter for service ports, programming interfaces, and legacy peripheral connections. Its CMOS logic compatibility allows direct interfacing with 3.3 V or 5 V digital controllers, while the internal charge pumps generate compliant bipolar output levels. The two-channel arrangement supports both transmit and receive paths in a single board area. Keep the interface connector and cable entry away from high-speed digital routes, and provide a stable ground reference between the two connected systems.
Recommended
Data Acquisition Equipment
The MAX3232IDW is useful in laboratory and industrial data-acquisition equipment that must communicate with a host computer over RS-232. Two full-duplex channels permit simultaneous command transmission and response reception, and the 250 kbit/s rate is sufficient for many legacy measurement protocols. The device's low 300 µA typical supply current helps in compact multi-instrument systems. For exposed laboratory leads, retain the ±15 kV ESD capability and consider connector-level protection and chassis grounding.
Recommended
Point-of-Sale Terminal Interface
The MAX3232IDW can provide the legacy RS-232 connection used by printers, scales, scanners, and other point-of-sale peripherals. The 3 V to 5.5 V supply range supports both controller platforms, while the two transmit and two receive channels cover common multi-peripheral arrangements. ESD protection is especially useful in retail equipment where service personnel repeatedly attach and detach cables. Keep the charge-pump capacitors compact and isolate the connector region from display, switching, and touch-controller circuitry.
Recommended
Test and Measurement Instrument Interface
The MAX3232IDW is appropriate for bench instruments and automated test systems that retain an RS-232 control or service port. It accepts 5 V logic, operates at up to 250 kbit/s, and avoids the external negative supply that older RS-232 implementations often required. The two-channel capability can connect a controller to two independent instruments. Use the manufacturer pin-description table when assigning driver, receiver, and charge-pump connections, and confirm EMI margins before finalizing the enclosure and cable layout.
Recommended
Recommended Products Summary
Engineering reference data for MAX3232IDW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX3232EIDWR | MAX3232EID | MAX3232EWE+ | MAX3232IDR | MAX232IDWR |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Package | SOIC-16 (DW) | SOIC-16 (DW) - same | SOIC-16 (DW) - same | SOIC-16 (DW) - same | SOIC-16 (DW) - same | SOIC-16 (DW) - same |
| Device Type | RS-232 transceiver | RS-232 transceiver | RS-232 transceiver | RS-232 transceiver | RS-232 transceiver | RS-232 transceiver |
| Supply Voltage Range | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 5 V |
Key Differentiators
- Broad single-rail operating range (vs MAX232IDWR)
- Manufacturer-recommended improved family option (vs MAX3232EIDWR)
- Integrated two-channel interface (vs MAX232IDWR)
Design Notes
Place all four 0.1 µF charge-pump capacitors close to their named MAX3232IDW pins, with the component ground connection providing a short return path. Keep the compact charge-pump loop away from the RS-232 connector and protected cable routing. This arrangement limits switching-current area and reduces the chance that charge-pump transients couple into sensitive receiver or logic circuitry.
Route RS-232 driver outputs directly toward the connector and keep receiver inputs away from switching regulators, clock lines, and high-current power paths. Respect the manufacturer-recommended clearance between charge-pump circuitry and interface traces. For externally accessible cables, evaluate connector-level protection in addition to the device's ±15 kV ESD rating rather than assuming that board-level protection handles every surge condition.
Do not substitute a 5 V-only MAX232-family device into a 3.3 V design without reviewing the power architecture. The MAX3232IDW operates from 3 V to 5.5 V, while the MAX232IDWR is identified as a 5 V-only cross-reference candidate. Also verify the exact pin assignments and external capacitor values in the selected replacement's datasheet before approving a board-level substitution.
Compliance Information
The device is an RS-232 interface IC; automotive qualification is not applicable. Compliance declarations were not identified and are therefore recorded as unknown.
