MC3487DE4 - Quad RS-422 Line Driver | Texas Instruments
MPN: MC3487DE4 ✓ פעילMC3487DE4 סקירה
A differential line driver is an interface IC that converts one logic input into two complementary outputs. This arrangement rejects much of the common-mode noise picked up by a cable, improving signal integrity in industrial environments. The MC3487 belongs to the broader interface-IC hierarchy: line driver → differential line driver → digital interface IC → semiconductor. Its four channels allow one package to drive four separate balanced links while sharing a common supply and ground reference.
Key features include four independent differential drivers, TTL-compatible buffered inputs, three-state output capability, fast transition times, and high-impedance inputs. Power-up and power-down protection helps prevent uncontrolled driver activity during supply changes. The buffered inputs reduce input loading, allowing the device to operate reliably with standard TTL and CMOS control logic when voltage-level compatibility is confirmed in the system design.
Technically, the MC3487 is a single-supply RS-422-focused transmitter rather than a complete bidirectional transceiver. It does not include receiver channels. Systems requiring two-way communication normally combine this driver with a separate differential receiver, such as a compatible RS-422 receiver IC. The differential outputs should be routed as a matched pair to preserve signal polarity and minimize common-mode conversion along the cable.
Typical applications include RS-422 test equipment, industrial automation links, programmable logic controller interfaces, data-acquisition systems, servo or motor-control signaling, point-to-point computer peripherals, and instrumentation. Designers should use twisted-pair wiring, provide a stable 5 V supply, connect the common ground reference, and account for the voltage drop and noise margin of the selected cable length.
The principal design consideration is ensuring that every connected receiver recognizes the driver’s differential output levels and that unused outputs are handled according to the manufacturer’s recommendations. PCB placement should minimize the distance between the interface connector and driver outputs, while avoiding noisy switching-current paths near the differential traces. This page combines device specifications, sourcing guidance, drop-in alternatives, and practical interface-design notes for engineers evaluating the MC3487DE4.
חלופות תחליף ישיר עבור MC3487DE4 — אותו מארז, תואם פין-לפין. חלקים במארז שונה הדורשים עיבוד מחדש של ה-PCB אינם נכללים.
אין חלופות תואמות Drop-in עבור מוצר זה.
בקשת חלופותMC3487DE4 מפרטים
| Product Type | Quadruple differential line driver |
| Number of Drivers | 4 independent channels |
| מתח אספקה | 5 V |
| Interface Standard | ANSI TIA/EIA-422-B |
| Recommendation | ITU Recommendation V.11 |
| Input Compatibility | TTL-compatible |
| Input Type | Buffered high-impedance input |
| Output State | Three-state |
| תצורת מוצא | Differential |
| מארז | 16-pin SOIC |
| סוג הרכבה | Surface mount |
| Transition Time | Fast transition time; exact value not stated |
| Power-Up Protection | Supported |
| Power-Down Protection | Supported |
תצורת פינים של MC3487DE4
| פין 1 | DATA A — TTL-compatible input for differential driver channel A |
| פין 2 | DATA B — TTL-compatible input for differential driver channel B |
| פין 3 | DATA C — TTL-compatible input for differential driver channel C |
| פין 4 | DATA D — TTL-compatible input for differential driver channel D |
| פין 5 | VCC — Positive power supply |
| פין 6 | GND — Ground reference |
| פין 7 | GND — Ground reference |
| פין 8 | GND — Ground reference |
| פין 9 | Y A — Non-inverting differential output for channel A |
| פין 10 | Z A — Inverting differential output for channel A |
| פין 11 | Y B — Non-inverting differential output for channel B |
| פין 12 | Z B — Inverting differential output for channel B |
| פין 13 | Y C — Non-inverting differential output for channel C |
| פין 14 | Z C — Inverting differential output for channel C |
| פין 15 | Y D — Non-inverting differential output for channel D |
| פין 16 | Z D — Inverting differential output for channel D |
יישומים טיפוסיים
MC3487DE4 מתאים עבור 6 יישוםs: Industrial RS-422 Control Links, Data-Acquisition Equipment, Test and Measurement Systems, Servo and Motor Control Signaling, Telecommunications and Network Equipment, Programmable Logic and Peripheral Interfaces.
Industrial RS-422 Control Links
The MC3487DE4 fits industrial control systems that distribute several digital command signals over balanced copper pairs. Its four independent differential drivers operate from one 5 V rail, allowing a controller to address up to four remote channels without allocating a separate transmitter package to each link. TTL-compatible buffered inputs ease connection to digital control logic, while differential outputs reduce susceptibility to common-mode noise found around motors, contactors, and switching equipment. Route each output pair as a matched twisted pair and include a compatible receiver at the remote equipment. The design must also preserve the correct output-enable states during reset and supply transitions, particularly when an attached receiver could otherwise interpret an uncontrolled output as valid data.
מומלץ
Data-Acquisition Equipment
The MC3487DE4 can transmit four balanced commands from a data-acquisition instrument to remote sensors, fixtures, or laboratory equipment. ANSI TIA/EIA-422-B and ITU Recommendation V.11 positioning make it appropriate for point-to-point links in which common-mode noise and cable length would challenge a single-ended output. TTL-compatible inputs allow the transmitter channels to be driven by ordinary digital control logic, while the 16-pin SOIC keeps the footprint compact. A differential receiver is required at the opposite end of every pair. Validate receiver thresholds, cable length, termination strategy, and grounding before release, because the driver specification alone does not establish the complete channel performance.
מומלץ
Test and Measurement Systems
The MC3487DE4 is useful in test and measurement equipment that requires several low-skew digital control channels routed from a main instrument to an external fixture. Four differential outputs reduce susceptibility to interference picked up between the instrument and fixture, while the single 5 V supply simplifies power architecture. The fast transition behavior supports modern digital command signals, but short stubs, controlled return paths, and a sound ground strategy remain essential. Use a compatible receiver at the fixture and configure unused channels according to the datasheet rather than allowing them to float without review.
מומלץ
Servo and Motor Control Signaling
The MC3487DE4 can provide balanced command outputs for servo, positioning, or motor-control subsystems where long interconnects run near switching nodes. Each differential channel is driven from a TTL-compatible command, and the four-channel count allows position, direction, enable, or related control signals to share one transmitter package. Balanced outputs are valuable because their common-mode rejection helps preserve command integrity in electrically noisy machinery. The implementation still needs an appropriate differential receiver, protective treatment for exposed cables, and careful separation from motor-current paths. Confirm propagation timing and output enable states against the motion-control controller’s requirements before using the device in a safety-related function.
מומלץ
Telecommunications and Network Equipment
The MC3487DE4 can drive four balanced point-to-point links within telecommunications equipment, interface backplanes, or external communication modules. Its single 5 V operating supply and three-state outputs support compact multi-channel interface cards, while differential signaling improves noise immunity over cable or backplane connections. The transmitter should be paired with an RS-422-compatible receiver, and each differential pair should remain closely coupled to minimize loop area and radiation. Designers should review the datasheet’s enable and supply-transition requirements, especially during hot plug, reset, and redundant-link switching, to prevent receivers from detecting invalid data.
מומלץ
Programmable Logic and Peripheral Interfaces
The MC3487DE4 is suitable for legacy processor or programmable-logic systems that need four balanced outputs beyond the electrical capability of ordinary TTL or CMOS pins. Buffered TTL-compatible inputs reduce command-loading concerns, while differential outputs extend the reach and noise margin of the interface. The transmitter can carry peripheral select, data, handshake, or control signals to a remote circuit card. Keep the output-enable signals under deterministic control so the receiving system remains in a known state during reset. For new high-speed designs, verify propagation delay and transition timing against the source-device specifications rather than assuming ordinary logic timing is sufficient.
מומלץ
סיכום מוצרים מומלצים
נתוני עזר הנדסיים עבור MC3487DE4 — השוואה, הנחיות תכנון ומידע על תאימות.
מדריך בחירה
הערות תכנון
Route each differential output pair as a tightly coupled pair on the PCB and use twisted-pair wiring at the connector. Keep the two conductors of a channel together so that external noise couples equally into both lines and is rejected by the receiver. Avoid routing the pairs adjacent to switching-power nodes or high-current motor traces. Provide a continuous ground reference between the transmitter and receiver because differential signaling rejects common-mode noise but does not remove the need for a common reference.
Do not assume that two quadruple differential drivers are interchangeable merely because both use 16-pin packages. Compare the input truth table, output-enable polarity, output impedance, propagation delay, differential polarity, and shutdown behavior before substituting a part. The MC3486 family is relevant for evaluation, but its enable organization differs from the MC3487. Also ensure that every receiver and connected system shares compatible logic levels; TTL-compatible input wording alone does not define a complete system-level voltage guarantee.
Use a stable 5 V supply and follow the manufacturer’s decoupling and grounding recommendations. Place the required bypass capacitor close to the device’s supply and ground pins to suppress supply transients caused by output switching. Account for the total supply current drawn by four active channels and by any enabled or disabled test conditions. Because the interface can be exposed to long cables, use connector-side protection or other surge-control measures selected for the installation environment.
Treat the driver as one element of a complete channel, not as an isolated logic output. Receiver thresholds, cable length, termination, topology, and data rate jointly determine whether the link operates reliably. Check the propagation and transition characteristics against the required command timing, and review output-enable sequencing during reset so the remote receiver cannot interpret uncontrolled or floating outputs as valid commands.
מידע על תאימות
No definitive environmental or automotive qualification status was established for the exact MC3487DE4 ordering code.