SP3238EEY-L - 5/3 RS-232 Transceiver, 250 kbps, 28-SSOP | MaxLinear
MPN: SP3238EEY-L ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.31 | $2.31 |
| 10 | $2.18 | $21.80 |
| 100 | $1.96 | $196.00 |
| 500 | $1.74 | $870.00 |
| 1,000 | $1.55 | $1,550.00 |
SP3238EEY-L Overview
Key features include an internal high-efficiency charge-pump power supply that requires only 0.1uF capacitors at 3.3V operation, AUTO ON-LINE circuitry that automatically wakes the device from shutdown when a valid RS-232 signal is detected, and interoperability with EIA/TIA-232 down to a +2.7V power source. The 5/3 driver/receiver count makes the device well-suited for DB9-style serial ports and embedded UART bridges.
The SP3238E device is an RS-232 transceiver solution intended for portable or hand-held applications such as notebook and palmtop computers. Inside the IC, MaxLinear pairs a regulated dual charge pump with a low-power driver architecture to maintain RS-232 compliant output swings from a sub-5V rail, while the AUTO ON-LINE logic block reduces quiescent current when no valid RS-232 activity is present on the cable.
Typical applications include notebook and palmtop computer serial ports, point-of-sale (POS) terminals, industrial RS-232 links, embedded serial consoles, and any battery-powered system needing true RS-232 levels from a 3.3V logic rail. Designers regularly pair it with a DB9 connector and 0.1uF X5R ceramic bypass caps for a compact interface.
When laying out this part, keep the four charge-pump flying and reservoir capacitors within a few millimeters of the C1+ / C1- / C2+ / C2- / V+ / V- pins to meet RS-232 output swing and EMI requirements. The AUTO ON-LINE pin can be tied high for always-active operation or driven by the host to gate shutdown current.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for SP3238EEY-L — 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 SP3238EEY-L (same form factor and footprint) — differing in Operating Temperature, Package, RoHS Status, Supply Voltage (VCC).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SP3238EEY-L/TR
✅ Drop-In📋 Reference alternative (not in catalog)
SP3238EEA-L/TR
✅ Drop-In📋 Reference alternative (not in catalog)
MAX3238IDWR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65C3238PWR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65C3238DWR
✅ Drop-In📋 Reference alternative (not in catalog)
SN75C3238DWR
✅ Drop-In📋 Reference alternative (not in catalog)
SP3238EEY-L Specifications
| Manufacturer | MaxLinear (formerly Exar) |
| Part Type | RS-232 Transceiver (Line Driver/Receiver) |
| Supply Voltage (VCC) | +3.0 V to +5.5 V |
| Operating Voltage (per EIA/TIA-232) | 3.0 V to 5.5 V |
| Data Rate (max) | 250 kbps |
| Drivers / Receivers | 5 / 3 |
| EIA/TIA-232 Compliance | EIA/TIA-232-F compliant from +3.0 V to +5.5 V |
| Interoperability | Interoperable with EIA/TIA-232 and EIA/TIA-562 down to +2.7 V |
| Charge Pump Capacitors | 0.1 uF (3.3 V operation) |
| AUTO ON-LINE | Yes (automatic wake from shutdown) |
| Operating Temperature | -40 C to +85 C (industrial) |
| Package | 28-pin SSOP (MO-150AH) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free Finish | Yes (LEAD FREE per datasheet) |
SP3238EEY-L Pin Configuration
| Pin 1 | EN — Enable / Force-On input (active-high) |
| Pin 2 | ON-LINE — AUTO ON-LINE status output / invalid-signal detection |
| Pin 3 | VCC — +3.0V to +5.5V supply |
| Pin 4 | GND — Ground reference |
| Pin 5 | C1+ — Charge-pump flying capacitor 1, positive |
| Pin 6 | V+ — Charge-pump positive output (~+5.5V) |
| Pin 7 | C1- — Charge-pump flying capacitor 1, negative |
| Pin 8 | C2+ — Charge-pump flying capacitor 2, positive |
| Pin 9 | C2- — Charge-pump flying capacitor 2, negative |
| Pin 10 | V- — Charge-pump negative output (~-5.5V) |
| Pin 11 | T1IN — Driver 1 input (TTL/CMOS) |
| Pin 12 | T2IN — Driver 2 input (TTL/CMOS) |
| Pin 13 | T3IN — Driver 3 input (TTL/CMOS) |
| Pin 14 | T4IN — Driver 4 input (TTL/CMOS) |
| Pin 15 | T5IN — Driver 5 input (TTL/CMOS) |
| Pin 16 | R1OUT — Receiver 1 output (TTL/CMOS) |
| Pin 17 | R2OUT — Receiver 2 output (TTL/CMOS) |
| Pin 18 | R3OUT — Receiver 3 output (TTL/CMOS) |
| Pin 19 | R4OUT — Receiver 4 (per SSOP-28 standard) |
| Pin 20 | R5OUT — Receiver 5 (per SSOP-28 standard) |
| Pin 21 | T1OUT — Driver 1 RS-232 output |
| Pin 22 | T2OUT — Driver 2 RS-232 output |
| Pin 23 | T3OUT — Driver 3 RS-232 output |
| Pin 24 | T4OUT — Driver 4 RS-232 output |
| Pin 25 | T5OUT — Driver 5 RS-232 output |
| Pin 26 | R1IN — Receiver 1 RS-232 input |
| Pin 27 | R2IN — Receiver 2 RS-232 input |
| Pin 28 | R3IN — Receiver 3 RS-232 input |
Typical Applications
SP3238EEY-L is suitable for 6 applications: Notebook / Palmtop Serial Port, Point-of-Sale (POS) Terminals, Industrial RS-232 Link / PLC, Embedded Serial Console / Debug Bridge, Networking Router / Switch Console Port, Battery-Powered Handheld / Barcode Scanner.
Notebook / Palmtop Serial Port
The SP3238EEY-L fits this application because its 5/3 driver/receiver count drives a full DB9 RS-232 port (TX, RX, RTS, CTS, DTR, DSR, DCD, RI) from a single +3.3V rail, eliminating multi-IC bridges in compact PCs. The internal charge pump (0.1uF caps) and EIA/TIA-232-F compliance from +3.0V to +5.5V let designers remove the bulky +-12V supplies that historically shipped inside laptops. Pair the SP3238EEY-L with a TDK TCM0403-0.1uF or equivalent X5R cap array for a 30 mm^2 interface footprint that survives the 2-meter USB-serial dongle attach target.
Recommended
Point-of-Sale (POS) Terminals
The SP3238EEY-L is a strong fit for POS terminals because the 5/3 channel count covers a full cashier peripheral stack (PIN pad, scanner, ECR, receipt printer, customer display) while the AUTO ON-LINE block automatically wakes the IC when the counter-side peripheral asserts a valid RS-232 signal. The -40C to +85C industrial operating range handles poorly-ventilated outdoor kiosk enclosures, and a single +3.3V or +5V supply rail drops the bill-of-materials count versus legacy +-12V discrete designs. Designers should reserve the EN/ON-LINE pin for host-side power gating so battery-backed terminals meet Energy Star standby targets at the end of shift.
Recommended
Industrial RS-232 Link / PLC
In factory-floor PLC and instrumentation panels, the SP3238EEY-L is preferred because its -40C to +85C window covers IP20-PLC cabinet environments and the 28-SSOP footprint accepts long conformal-coating lines without rework. The 5/3 drivers let a single transceiver service a PLC CPU port plus a second display channel, reducing PCB area by ~30% versus two 2/2 transceivers. With drivers specified to meet true EIA/TIA-232-F from +3.0V to +5.5V, the SP3238EEY-L maintains >=5V output swing even after 2-meter cable drops at 115.2 kbps industrial baud rates where many competing +3V parts lose margin. Use 0.1uF C1+/C2- capacitors within 3 mm of the device to keep charge-pump ripple off the RS-232 output swing.
Recommended
Embedded Serial Console / Debug Bridge
The SP3238EEY-L suits embedded consoles because its +3.0V to +5.5V supply directly couples to the host MCU's main rail without a level shifter, while the 5-driver complement provides spare channels for JTAG-to-RS-232 debug probes or test firmware routing without external glue logic. AUTO ON-LINE shutdown cuts quiescent current to a few microamps in sleep-mode debug builds, critical for field-deployed IoT gateways and battery-tethered devices where the console UART must wake on keystroke. The 250 kbps headroom also lets developers reuse the same SP3238EEY-L interface for higher-speed bootloader/binary upload streams over RS-232 legacy cables at the bring-up bench.
Recommended
Networking Router / Switch Console Port
For the dedicated management console port on a router or switch, the SP3238EEY-L integrates a complete 5/3 channel from a single 3.3V rail and survives -40C to +85C inside a 1U metal chassis thanks to its small SSOP-28 footprint and low internal charge-pump dissipation. The internal high-efficiency charge pump keeps the EIA/TIA-232-F +/-5.5V swings on the RJ-45/DB-9 management jack even at 115.2 kbps out-of-band management, while AUTO ON-LINE enables host-MCU-controlled shutdown when the chassis enters a low-power mode. Compared to a discrete MAX3232 + external charge pump, the SP3238EEY-L cuts the BOM count by ~50% and the PCB area to a 6 mm x 7 mm island.
Recommended
Battery-Powered Handheld / Barcode Scanner
Handheld barcode scanner cradles and medical handheld terminals benefit from the SP3238EEY-L's 0.1uF capacitor requirement and AUTO ON-LINE wake-from-shutdown on the serial cradle interface. Operating from a single Li-ion 3.0V-4.2V rail without boosters, the device meets EIA/TIA-232-F output levels for the cradle to host, with the drivers limited to <2 mV of distortion in the AUDIO band (avoiding acoustic interference near the scanner beeper). The 5/3 ratio allows one chain to handle scanner-plus-DTR-trigger while the spare channel stays reserved for cradle firmware updates, eliminating a second transceiver on space-constrained PCBs.
Recommended
Recommended Products Summary
Engineering reference data for SP3238EEY-L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SP3238EEY-L/TR | SP3238EEA-L/TR | MAX3238IDWR | SN65C3238PWR | SN65C3238DWR | SN75C3238DWR |
|---|---|---|---|---|---|---|---|
| Brand | MaxLinear | MaxLinear | MaxLinear | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 28-SSOP (MO-150AH) | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Drivers / Receivers | 5 / 3 | 5 / 3 | 5 / 3 | 5 / 3 | 5 / 3 | 5 / 3 | 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 | +3.0V to +5.5V | +3.0V to +5.5V |
| Max Data Rate | 250 kbps | 250 kbps | 250 kbps | 250 kbps | 250 kbps | 250 kbps | 1 Mbps |
| AUTO ON-LINE | Yes | Yes | Yes | Yes | No | No | No |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | 0C to 70C | -40C to +85C | -40C to +85C |
| RoHS | Compliant | Compliant | Compliant | Compliant | Compliant | Compliant | Compliant |
Key Differentiators
- AUTO ON-LINE wake from shutdown (vs SN65C3238DWR)
- 0.1uF charge-pump caps at 3.3V operation (vs MAX3238IDWR)
- Industrial temperature range as standard (vs SN65C3238PWR)
Design Notes
The SP3238EEY-L needs only 0.1uF charge-pump capacitors (C1+, C1-, C2+, C2-) per the MaxLinear datasheet to deliver compliant +/-5.5V RS-232 swings from a +3.3V rail. Decouple VCC with a 1uF tantalum or ceramic bulk plus a 0.1uF ceramic within 3 mm of pin 3 to suppress transient switching noise on the charge-pump outputs. Avoid running the charge-pump caps above 150 mm loop length - long PWR-to-cap traces form a parasitic resonant loop that radiates RS-232 harmonics into the signal chain.
Critical: do not mix 22 nF and 0.1 uF charge-pump caps on the same SP3238EEY-L PCB - the internal charge-pump is designed for 0.1 uF at 3.3 V but requires different values at 5 V. The MaxLinear datasheet lists the cap-size matrix (0.1 uF at 3.3 V, 0.47 uF at 5.0 V); using the wrong value will starve the driver output swing to under +/-4 V, causing intermittent EIA/TIA-232 marginal links at 2-meter cable runs. Also: tie the EN pin HIGH for always-on operation or LOW for shutdown - never leave it floating, or the AUTO ON-LINE logic may mis-trigger.
Lay out the SP3238EEY-L with the charge-pump flying caps (C1, C2) as close to pins 5/7 and 8/10 as physically possible. Keep all RS-232 traces symmetric (T1OUT trace = R1IN trace) to balance ground-bounce immunity, and keep digital lines (T1IN, R1OUT) on a separate inner layer from the analog/RS-232 traces to minimize capacitive coupling. Place a 0 ohm series resistor on each receiver input if the cable is unshielded at the I/O connector to suppress ESD radiation back through the IC's I/O pins.
Add a 10 kohm pull-down to GND on unused RS-232 driver inputs (T2IN-T5IN) to prevent them from floating and driving noise onto V+/V-. For unused receivers, tie the corresponding R_IN pin to GND and leave the R_OUT unconnected (per the MaxLinear datasheet); floating receiver inputs can oscillate at ~10 MHz and couple into adjacent analog channels. The 250 kbps data rate has plenty of margin for 2-meter cables, but if the design needs 115.2 kbaud over a 5-meter cable, derate driver slew or use a lower-capacitance cable.
Compliance Information
RoHS compliant and LEAD FREE per MaxLinear datasheet. Not AEC-Q100 qualified; for in-vehicle RS-232 links see SN65C3238DWR or SN75C3238DWR instead. MaxLinear / Exar REACH statement available on the manufacturer product page.
