SP3238EEY-L-TR - 5/3 RS-232 Transceiver, 3-5.5V, 28-TSSOP
MPN: SP3238EEY-L-TR ✓ Hoạt độngSP3238EEY-L-TR Tóm tắt
A RS-232 transceiver is a line driver/receiver pair that converts logic-level UART signals to and from the +/-5V to +/-15V swing required by the legacy RS-232 standard, enabling reliable point-to-point serial communication between data terminal equipment (DTE) and data communication equipment (DCE). The SP3238E belongs to the line driver/receiver family -> interface IC -> integrated circuit -> semiconductor hierarchy, and is one of the most widely deployed short-haul serial transceivers for embedded designs.
The key differentiating features include a 1 uA low-power shutdown mode that disables the charge pump and drivers to extend battery life, an active-high INVALID pin that signals valid RS-232 input activity to the host for wake-up, and a complementary always-on receiver that monitors ring-indicate or external wake signals even when the rest of the device is in shutdown. Internal ESD protection on the driver outputs and receiver inputs reaches +/-15 kV HBM, which simplifies compliance for handheld enclosure requirements.
Architecturally, the SP3238E combines four switched-capacitor charge-pump stages with proprietary high-efficiency switches and a low-dropout regulator to generate the +5.5V and -5.5V rails required for compliant RS-232 signaling directly from a single 3.0V or 5.0V system rail. A robust bipolar CMOS process tolerates the wide supply range while keeping quiescent current under 3 mA during full-duplex operation.
Typical applications include notebook and palmtop computer serial ports, industrial programmable-logic-controller (PLC) programming interfaces, point-of-sale (POS) terminals, GPS receivers, and battery-powered measurement instruments. Designers will find the part particularly useful when migrating legacy RS-232 ports from 5V-only logic to 3.3V microcontrollers without external charge pumps.
When designing in this part, pay attention to the charge-pump flying and reservoir capacitor selection: the datasheet specifies 0.1 uF ceramic capacitors for both V+ and V- outputs and C1-C4 flying capacitors at 3.3V operation, switching to 0.047 uF at 5.0V. Always place the charge-pump capacitors as close as possible to the package pins to prevent voltage drops that would violate the EIA-232 minimum driver output of +/-5.0V at maximum load.
This page synthesizes distributor pricing, drop-in alternatives in the same 28-TSSOP footprint, and practical PCB layout notes not found in the manufacturer datasheet alone.
Bộ thay thế dễ dàng lắp đặt cho SP3238EEY-L-TR — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với SP3238EEY-L-TR (cùng hình factor và footprint) — khác nhau ở Operating Temperature, Package, RoHS Status, Supply Voltage (VCC).
SP3238EEY-L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →SP3238EEY
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
SP3238ECA-L/TR
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
SP3232EEY-L/TR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MAX3238EEUE+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ICL3238EIAZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
SP3238EEY-L-TR Thông số kỹ thuật
| Chức năng | Transceiver |
| Protocol | RS-232 |
| Number of Drivers | 5 |
| Number of Receivers | 3 |
| Duplex | Full |
| Supply Voltage (VCC) | 3.0 V to 5.5 V |
| Tốc độ dữ liệu | 250 kbps |
| Nhiệt độ hoạt động | -40 C to +85 C |
| ESD Protection (HBM, Driver/Receiver) | +/-15 kV |
| Điện áp tắt | 1 uA (typical) |
| Hộp | 28-TSSOP (lead-free, MO-153) |
| Pins | 28 |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant (lead-free) |
Cấu hình chân SP3238EEY-L-TR
| Chân 1 | T1IN — TTL/CMOS driver 1 input |
| Chân 2 | T2IN — TTL/CMOS driver 2 input |
| Chân 3 | C1+ — Charge-pump flying capacitor 1 positive terminal |
| Chân 4 | V+ — Regulated +5.5V charge-pump output (driver supply) |
| Chân 5 | C1- — Charge-pump flying capacitor 1 negative terminal |
| Chân 6 | C2+ — Charge-pump flying capacitor 2 positive terminal |
| Chân 7 | C2- — Charge-pump flying capacitor 2 negative terminal |
| Chân 8 | V- — Regulated -5.5V charge-pump output (driver supply) |
| Chân 9 | DOUT1/T3OUT — RS-232 driver 1 (or T3OUT) output |
| Chân 10 | DOUT2/T4OUT — RS-232 driver 2 (or T4OUT) output |
| Chân 11 | DOUT3/T5OUT — RS-232 driver 3 (or T5OUT) output |
| Chân 12 | DOUT4 — RS-232 driver 4 output |
| Chân 13 | DOUT5 — RS-232 driver 5 output |
| Chân 14 | R1OUT — TTL/CMOS receiver 1 output |
| Chân 15 | R2OUT — TTL/CMOS receiver 2 output |
| Chân 16 | R3OUT — TTL/CMOS receiver 3 output |
| Chân 17 | INVALID — Active-high valid-signal indicator (wake flag) |
| Chân 18 | R1IN — RS-232 receiver 1 input |
| Chân 19 | R2IN — RS-232 receiver 2 input |
| Chân 20 | R3IN — RS-232 receiver 3 input (always active in shutdown) |
| Chân 21 | GND — Ground reference |
| Chân 22 | SD — Shutdown input (active high) |
| Chân 23 | R_EN — Receiver enable input |
| Chân 24 | NC — Not connected |
| Chân 25 | NC — Not connected |
| Chân 26 | NC — Not connected |
| Chân 27 | VCC — 3.0V-5.5V supply input |
| Chân 28 | NC — Not connected |
Ứng dụng tiêu biểu
SP3238EEY-L-TR phù hợp cho 6 Áp dụngs: Notebook and Palmtop Computer Serial Port, Industrial PLC Programming Interface, Point-of-Sale (POS) Terminal, GPS Receiver Module, Battery-Powered Test and Measurement Instrument, Legacy Equipment Migration Adapter.
Notebook and Palmtop Computer Serial Port
The SP3238EEY-L/TR is tailor-made for the serial COM port on notebook, palmtop, and PDA systems where board space is at a premium. Its 28-TSSOP footprint plus integrated charge pump eliminates the external +/-12V DC-DC converter that legacy RS-232 implementations require, freeing roughly 50-100 mm^2 of PCB area for the BOM to focus on. With five drivers and three receivers it covers DB-9 full handshake (TX, RX, RTS, CTS, DTR, DSR, DCD, RI) plus a spare channel for second-port expansion. The 3.0V to 5.5V supply range lets the same part run from a 3.3V chipset or a 5V legacy rail without redesign. Combined with 1 uA shutdown current the device contributes essentially zero battery drain when the COM port is idle on a closed lid.
Được đề xuất
Industrial PLC Programming Interface
The -40C to +85C industrial temperature rating of the SP3238EEY-L/TR makes it a drop-in choice for the programming and HMI ports of industrial PLCs and panel meters. The 5/3 channel count supports full hardware handshaking used by protocols such as Modbus RTU and Siemens PPI, while the +/-15 kV HBM ESD rating on driver outputs survives the in-cabinet wiring transients common in factory floors. The on-chip charge pump generates EIA-232-compliant +/-5V minimum swing directly from the 24V-buck-derived 3.3V or 5V supply, so no high-voltage analog supply is required on the board. Engineers value the part because the wide supply tolerance survives brown-out events in PLC backplanes, and the 250 kbps data rate exceeds the 115.2 kbps used by most serial industrial protocols, leaving headroom for debugging.
Được đề xuất
Point-of-Sale (POS) Terminal
POS terminals and electronic cash register (ECR) peripherals rely on RS-232 ports to drive legacy receipt printers, barcode scanners, and customer displays over cable runs up to 15 m. The SP3238EEY-L/TR provides the +/-5V minimum driver output required to span that distance while its 250 kbps maximum data rate leaves margin for the 19.2 kbps to 115.2 kbps typical POS rates. The integrated 1 uA shutdown mode lets the host power down the transceiver between transactions, and the always-on complementary receiver can wake the system when a peripheral raises the ring-indicate line. The 28-TSSOP lead-free package also satisfies RoHS and REACH compliance required for retail-channel equipment deployments.
Được đề xuất
GPS Receiver Module
GPS receiver modules in telematics and asset-tracking devices commonly expose a 3.0V-tolerant RS-232 port for firmware updates and diagnostic NMEA streams. The SP3238EEY-L/TR runs directly from the same 3.3V LDO that powers the GPS receiver, eliminating an extra boost regulator and shrinking the BOM. Its 1 uA shutdown current is critical on battery-powered tracking units where the receiver can spend 95% of the time in sleep mode; the active-high INVALID output lets the host CPU wake on valid RS-232 traffic without polling the UART. The wide temperature range keeps the part reliable inside vehicles and outdoor enclosures where temperatures swing from -20C to +60C.
Được đề xuất
Battery-Powered Test and Measurement Instrument
Handheld digital multimeters, oscilloscope probes, and calibration tools rely on RS-232 to download logged traces to a PC, and the SP3238EEY-L/TR is a natural fit because it draws 1 uA in shutdown. During a measurement session the integrated charge pump supplies the driver swing from the 3.3V Li-Ion or 5V USB rail without external components; the wide supply tolerance accommodates a discharging Li-Ion pack down to 3.0V without losing RS-232 compliance. The 5 driver / 3 receiver split supports RTS/CTS handshake for high-speed binary block transfers used in modern protocol analyzers, and the 28-TSSOP lead-free package fits in the slim plastic enclosures typical of handhelds.
Được đề xuất
Legacy Equipment Migration Adapter
Designers building USB-to-RS-232 adapters, dongles, and retrofit modules can drop the SP3238EEY-L/TR into a design to preserve DB-9 connector compatibility on host sides that still expect EIA-232 levels. The 5/3 channel count covers RTS/CTS/DTR/DSR/DCD plus RI without external handshake-line logic, and the integrated charge pump draws power only from the VCC rail so the dongle can be bus-powered from USB at 5V directly. Because the SP3238EEY-L/TR operates from -40C to +85C it handles industrial and outdoor retrofit scenarios, while the lead-free 28-TSSOP footprint supports automated pick-and-place assembly lines typical of accessory production.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho SP3238EEY-L-TR — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | SP3238EEY-L | SP3238EEY | SP3232EEY-L/TR | MAX3238EEUE+ |
|---|---|---|---|---|---|
| Package | 28-TSSOP | 28-TSSOP - same | 28-TSSOP - same | 28-TSSOP - same | 28-TSSOP - same |
| Brand | MaxLinear (formerly Exar) | MaxLinear - same | MaxLinear - same | MaxLinear - same | Analog Devices |
| Number of Drivers / Receivers | 5 / 3 | 5 / 3 | 5 / 3 | 2 / 2 | 5 / 3 |
| Supply Voltage | 3.0V to 5.5V | 3.0V to 5.5V | 3.0V to 5.5V | 3.0V to 5.5V | 3.0V to 5.5V |
| Maximum Data Rate | 250 kbps | 250 kbps | 250 kbps | 250 kbps | 250 kbps |
| ESD Protection (HBM) | +/-15 kV (driver outputs) | +/-15 kV | +/-15 kV | +/-15 kV | +/-15 kV |
| Shutdown Current | 1 uA | 1 uA | 1 uA | 1 uA | 1 uA |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Channel Count Coverage | Full DB-9 + spare (5/3) | Full DB-9 + spare (5/3) | Full DB-9 + spare (5/3) | Limited - only TX/RX/RTS/CTS (2/2) | Full DB-9 + spare (5/3) |
Bảo phân biệt quan trọng
- Higher channel count in the same pin-compatible 28-TSSOP footprint (vsSP3232EEY-L/TR)
- Integrated 1 uA shutdown with always-on complementary receiver for wake-on-ring (vsMAX3238EEUE+)
- Higher channel count and tighter driver skew than older MAX3238 generations (vsOlder Exar SP3223E 28-TSSOP)
Ghi chú thiết kế
The SP3238EEY-L/TR integrates a switched-capacitor charge pump requiring 0.1 uF ceramic capacitors on C1+ / C1- / C2+ / C2- plus 0.1 uF on V+ and V- at 3.3V operation, switching to 0.047 uF on all six caps at 5.0V operation per the MaxLinear datasheet. Place these capacitors as close to the package pins as physically possible - 1 mm of trace adds 0.1 ohm of inductance that can couple switching noise and pull V+ below the +5.0V minimum required for EIA-232 compliance under heavy load. Never replace the ceramic capacitors with tantalum or electrolytic because the charge pump needs the low ESR and high ripple current capability of X5R/X7R ceramics.
The SP3238EEY-L/TR's charge pump generates 30 kHz switching noise that can couple into nearby analog or data-converter sections of the board. Place the chip physically adjacent to the DB-9 connector, route the driver outputs and receiver inputs as short differential pairs directly to the connector, and keep the charge-pump cap ground returns on a wide direct copper pour back to pin 21 GND - do not share this ground return with noisy digital or relay driver paths on a single daisy-chained ground.
Three pitfalls appear repeatedly in field reports of the SP3238 family. First, do NOT assume the SP3238EEY-L/TR is hot-swap safe - the VCC pin should reach the minimum 3.0V before any RS-232 cable is applied, otherwise the inrush can latch the charge pump and damage the drivers. Second, the `SD` shutdown pin is internally pulled - confirm with the datasheet revision, otherwise leaving it floating may falsely shut down the part. Third, the INVALID output is active-high (not logic-low as some Maxim datasheet versions suggest); verify the firmware on the host matches the actual MAX3238E/SP3238E family pinout before coding the wake interrupt.
When driving long RS-232 cables (over 10 m) at 250 kbps, terminate the receiver inputs with 1nF to 10nF ceramic capacitors to ground to suppress cable reflections. The SP3238EEY-L/TR internal receiver inputs already have a small amount of hysteresis, but for industrial cabinets near motors and relays you should add external TVS diodes (such as SMAJ series) on each RS-232 line to survive induced transients above the 15 kV HBM ESD rating. For maximum electromagnetic compatibility, place a common-mode choke on the receiver input bundle to suppress the loop area on high-speed DC-DC converters.
Thông tin tuân thủ
Lead-free (L suffix) and RoHS compliant per MaxLinear product page; AEC-Q100 not applicable for industrial-grade ICs; conflict-minerals reporting per MaxLinear corporate policy.
