ADM239LAR - 5V RS-232 Interface with DC-DC | Analog Devices
MPN: ADM239LAR ✓ NakahandaADM239LAR Ulas
An RS-232 transceiver is an interface IC that converts logic-level digital signals into differential, bipolar RS-232 signals and converts received RS-232 signals back into CMOS logic levels. The RS-232 transceiver belongs to the serial-interface hierarchy, which includes interface ICs, line drivers and receivers, communication transceivers, and broader data-communication semiconductors. It is designed for equipment-to-equipment communication over cables where voltage levels exceed ordinary CMOS input and output ranges.
The ADM239LAR's principal advantages include operation from one 5 V supply, compliance with EIA-232-E and V.28 specifications, a maximum data rate of 120 kB/s, and an integrated DC-DC converter that generates the elevated RS-232 output voltage. Its 9 V output swing provides useful noise margin over the approximately 2 V RS-232 transition region. Low-power shutdown reduces consumption when the interface is not required, while the receiver remains active during shutdown.
The integrated charge-pump circuit develops the bipolar transmitter voltage required by RS-232 from the single 5 V supply. The manufacturer datasheet specifies small 1 μF capacitors for the charge-pump circuit. Three transmitters provide enough channels for common control, status, and data paths, while five receivers allow the opposite direction of the link to carry several signals. The CMOS implementation supports integration into systems that already operate from 5 V rather than requiring the additional negative supply traditionally associated with RS-232.
Typical uses include industrial control links, point-of-sale equipment, test and measurement instruments, data-acquisition systems, and embedded equipment interfaces. In each case, the ADM239LAR can translate between a 5 V controller and an external RS-232 port. The 120 kB/s rate is suitable for moderate-speed serial links, while the integrated DC-DC converter simplifies implementation where only a positive 5 V rail is available.
The main design consideration is external line protection. Although the receiver input is specified to 30 V, exposed RS-232 ports may encounter larger transients or incorrect polarity. Appropriate surge and ESD protection should be added where the cable environment requires it, and unused driver outputs should be handled according to the manufacturer recommendations.
This page consolidates the verified ADM239LAR specifications, sourcing information, procurement details, interface-application guidance, and data gaps that are not resolved by the supplied manufacturer and distributor records.
Mga alternatibo na pwedeng ilagay na ADM239LAR — parehas na package, pin-to-pin na katugmang. Hindi kasama ang mga bahagi ng iba't-ibang package na nangangailangan ng pagpapaayos ng PCB.
Wala ng magagamit na drop-in alternatibo para sa produkto na ito.
Hilingin ang AlternatiboADM239LAR Mga Pinakamataas na Rating at Electrical Characteristics
| Product Type | 5 V powered CMOS RS-232 drivers and receivers |
| Volte ng Pagbibigay | 5 V |
| Driver Channels | 3 channels |
| Receiver Channels | 5 channels |
| Maximum Data Rate | 120 kB/s |
| RS-232 Output Swing | 9 V |
| Charge-Pump Capacitance | 1 μF |
| Receiver Input Voltage Rating | 30 V |
| Shutdown Feature | Low-power shutdown |
| Receiver State During Shutdown | Receivers active |
| Compliance | EIA-232-E and V.28 |
| Packhaging | 24-lead SOIC |
| Package Width | 0.295 inch (7.50 mm) |
| Terminal Count | 24 terminals |
| Uri ng Pagpapasok | Gull-wing surface mount |
| Temperature Grade | Industrial |
Gabay sa Pin Configuration ng ADM239LAR 0.295 inch (7.50 mm)
Pin configuration para sa ADM239LAR (0.295 inch (7.50 mm) package). Ang power device na ito ay may gate, drain, at source terminals. Para sa mga non-polarized package, sumangguni sa datasheet ng manufacturer para sa eksaktong oryentasyon ng pin 1 at mga detalye ng footprint. Kasama sa mga karaniwang aplikasyon ang disenyo ng power supply, motor driving, at load switching.
Wala ng detalyadong pinout data na magagamit para sa ADM239LAR.
Sumangguni sa datasheet para sa buong pin configuration.
Tipikal na mga Gamit
ADM239LAR ay nararapat para sa 6 aplikasyons: Industrial Control Equipment, Test and Measurement Instrumentation, Point-of-Sale and Data Acquisition, Embedded Equipment Communication, Security and Access Systems, Medical and Diagnostic Equipment.
Industrial Control Equipment
The ADM239LAR suits industrial control equipment that must expose a multi-channel RS-232 port while operating from a 5 V control rail. Its 3 drivers support outgoing control or status signals, while 5 receivers provide more incoming channels than a compact two-direction interface typically offers. The 120 kB/s rate is suitable for supervisory links, configuration channels, and legacy machine controllers. The integrated DC-DC converter eliminates the need for a separate negative supply, while the 9 V output swing preserves RS-232 transition margin. Designers should still add cable-side surge protection because the verified 30 V receiver rating is not equivalent to unlimited transient immunity.
Inirekomenda
Test and Measurement Instrumentation
The ADM239LAR can serve legacy RS-232 control and measurement ports in laboratory instruments that already use 5 V CMOS logic. Three transmitter channels can carry commands, triggers, or service data, and five receiver channels can accept status and measurement acknowledgements. Its 120 kB/s maximum data rate is appropriate for instrument-control traffic that is not a continuous high-throughput data stream. The single 5 V supply arrangement simplifies isolation and power partitioning inside compact equipment, although engineers should check line capacitance, baud rate, and receiver thresholds against the actual cable.
Inirekomenda
Point-of-Sale and Data Acquisition
The ADM239LAR is appropriate for point-of-sale terminals, barcode equipment, and compact data-acquisition units that need more RS-232 channels than a minimal single-transceiver interface. Three outputs can support printer, scanner, or peripheral-control functions, while five inputs can monitor peripheral status. The integrated DC-DC converter and 1 μF charge-pump capacitors reduce the number of supporting power-supply components, and the 120 kB/s rate accommodates conventional transaction traffic. The 24-lead SOIC footprint should be reserved on a new design because verified drop-in alternatives in a smaller package cannot replace it directly.
Inirekomenda
Embedded Equipment Communication
The ADM239LAR can connect an embedded 5 V controller to an external RS-232 service port on industrial appliances and communication equipment. Using three drivers and five receivers allows the host to exchange multiple command, status, and diagnostic signals without three separate transceiver packages. Its 120 kB/s data rate is sufficient for configuration protocols, boot logs, and supervisory messages. The integrated DC-DC converter is valuable where the board lacks a negative voltage rail, and active receivers during shutdown can preserve incoming-status detection. Firmware and hardware should still define safe behavior for disconnected or shorted RS-232 lines.
Inirekomenda
Security and Access Systems
The ADM239LAR can support legacy RS-232 connections in access-control panels, alarm interfaces, and peripheral security equipment where a 5 V controller must communicate with external devices. The three transmitter channels can carry commands and acknowledgements, and five receiver channels can read sensors or status lines. The 120 kB/s rate is suitable for periodic supervisory traffic rather than high-bandwidth video transfer. Low-power shutdown is useful in duty-cycled equipment, while receiver operation during shutdown helps the controller detect incoming activity. Installation practice should include appropriate cable routing and line protection because external conductors may be exposed to surges.
Inirekomenda
Medical and Diagnostic Equipment
The ADM239LAR can support RS-232 service and legacy control ports in medical or diagnostic equipment that retains a 5 V logic supply. Its multiple channels provide flexible separation between commands, results, and status signals, while the 120 kB/s rate is suitable for instrument-control and service traffic. The single-supply DC-DC converter simplifies power conversion in systems where creating a negative RS-232 rail would add board area. Because the verified records do not confirm medical-specific qualification, this use should be treated as an electronic-interface function rather than evidence of regulatory approval. Appropriate isolation, leakage, and system-risk controls must be evaluated independently.
Inirekomenda
Impormasyon ng Talumpati sa Engineering for ADM239LAR — ikabit, gabay sa disenyo, at impormasyon ng pagsunod sa kautusan.
Paunawang Hanapin
Ikabit sa Mga Alternatibo
| Parametro | Ito ang Producto |
|---|---|
| Package | 24-lead SOIC |
| Brand | Analog Devices |
| Product Type | RS-232 drivers and receivers |
| Supply Voltage | 5 V |
| Driver Channels | 3 channels |
| Receiver Channels | 5 channels |
| Maximum Data Rate | 120 kB/s |
| RS-232 Output Swing | 9 V |
| Receiver Input Voltage Rating | 30 V |
| Charge-Pump Capacitance | 1 μF |
| Shutdown | Low-power shutdown; receivers active |
Pangunahing mga Pagkakaiba
- Integrated single-supply DC-DC conversion (kumpara saNo verified drop-in alternative)
- Asymmetric channel allocation (kumpara saNo verified drop-in alternative)
- Receiver monitoring during shutdown (kumpara saNo verified drop-in alternative)
Talaan ng Disenyo
Provide a stable 5 V supply and place the interface's supply decoupling close to the device power pins. The on-board DC-DC converter generates the RS-232 transmitter voltage, so the power rail must support both the CMOS logic load and charge-pump current. Follow the manufacturer datasheet for the exact input capacitor, voltage, and layout requirements before releasing the PCB.
Keep the 1 μF charge-pump capacitor connections and RS-232 driver outputs short, and route the receiver inputs away from switching nodes and high-current return paths. Maintain the differential geometry of connected RS-232 driver and receiver pairs. Because the supplied records do not contain the complete pin table, verify every connection against the manufacturer pin diagram before fabrication.
Do not treat the 30 V receiver input rating as unlimited transient protection. Add appropriately rated ESD or surge protection for cables that leave the enclosure, and confirm that protection capacitance will not degrade the intended 120 kB/s signaling. Also verify unused outputs and shutdown control states against the datasheet; generic RS-232 guidance may not match the ADM239LAR implementation.
Impormasyon ng Pagsunod sa Kautusan
The verified datasheet summary states that the ADM239LAR meets EIA-232-E and V.28 specifications. The supplied records do not explicitly confirm material-compliance or automotive-qualification status.
