K4A4G165WG-BCWE 完全ガイド：Samsung 4Gb DDR4-3200 SDRAMの仕様、代替品、調達（2026年）

The K4A4G165WG-BCWE is a Samsung 4Gbit DDR4 SDRAM memory IC organized as 256M x 16, operating at data rates up to 3200 Mbps from a single 1.2V supply, with a 19 ns access time. It comes in a 96-ball FBGA surface-mount package and is rated for 0C to +85C operation. The part is actively manufactured by Samsung, carries RoHS compliance per its JLCPCB listing, and is widely in stock as of 2026-09-23: XAIPART lists 99,999 units available with MOQ of 1, priced from $23.15 at single units down to $16.90 at 1000 units. The x16 organization and compact FBGA-96 footprint make it a strong fit for embedded computing, networking, set-top boxes, industrial control, and PC memory modules where the memory controller supports DDR4-3200 over a 16-bit bus. This guide covers verified specifications, design-in practices, drop-in alternatives, and current sourcing, all anchored to the K4A4G165WG-BCWE product page on XAIPART.

What Is the K4A4G165WG-BCWE and Why Does It Matter for Memory Designs?

The K4A4G165WG-BCWE is Samsung's 4Gbit DDR4 SDRAM in a x16 organization, part of the fourth-generation DDR DRAM family. DDR4 lowered the operating voltage from DDR3's 1.5V to 1.2V, doubled bank groups to eight for improved access parallelism, and raised data rates to 3200 Mbps. Per Samsung's DDR4 portfolio data, this generation cuts memory subsystem power by roughly 25% compared with DDR3 - a meaningful saving in always-on and thermally limited designs.

The device implements the DDR4 features that matter at speed: bank group architecture, on-die termination (ODT), and data mask/data strobe signaling for reliable high-speed transfers. Its 4Gbit density in a x16 organization suits processors and SoCs whose memory controllers expose 16-bit or 32-bit buses rather than full 64-bit channels, which is common in embedded, networking, and consumer SoCs. The 19 ns access time supports the low random latencies expected in desktop and embedded workloads.

Takeaway: If your controller supports DDR4-3200 on a x16 bus and your thermal envelope is commercial grade, this part delivers 4Gb of main memory at 1.2V in a minimal footprint.

How Do You Select and Design In the K4A4G165WG-BCWE?

Design-in starts with three compatibility checks. First, confirm your memory controller supports DDR4-3200 speed bins; for designs clocked at DDR4-2133/2400/2666, a lower speed bin such as the K4A4G165WE-BCRC delivers the same capacity in the same FBGA-96 footprint at potentially lower cost with wider timing margin at slower clocks. Second, verify the controller supports 4Gb densities and x16 organization - a controller that only maps 64-bit-wide x8 devices will not initialize this part correctly. Third, confirm your ambient thermal profile stays within the 0C to +85C commercial range; for extended ranges of -40C to +95C, consider Samsung parts with an industrial temperature suffix such as the K4AAG165WA-BCWE class listed on LCSC, and verify the exact temperature suffix in the ordering code before qualification.

Board layout follows standard DDR4 signal-integrity practice. Route DQ/DM/DQS groups length-matched and impedance-controlled; provide proper VDDQ decoupling at the 1.2V rail; and use fly-by command/address topology per Samsung's DDR4 design guide. The FBGA-96 ballout is documented in the Samsung DDR4 datasheet PDF - download it and extract exact ball coordinates (letter-number grid covering DQ, DQS/DM, CK/CKE, CS, RAS/CAS/WE, address, power, and ground balls) before layout. Do not lay out from a secondary source's ball map.

For controller configuration, verify CAS latency and clock period (tCK) against the Samsung datasheet for the specific speed bin before programming timing registers; these bin-specific values should be taken from the official datasheet rather than assumed. On-die termination handles much of the line-termination burden at 3200 MT/s, reducing the external resistor network compared with earlier generations.

Takeaway: Confirm controller speed-bin and density support, extract timing parameters from the Samsung datasheet, and route DQ groups with length matching - then this part drops onto the board without surprises.

Which Alternatives Can Replace the K4A4G165WG-BCWE?

The closest drop-in replacements come from Samsung's own family, preserving the 4Gb 256M x 16 DDR4 organization and the FBGA-96 pin-to-pin ballout, so no PCB rework is needed - only firmware/SPD timing re-qualification per Samsung datasheets. No Micron, Nanya, or Winbond cross-brand equivalent was confirmed in the verified cross-reference data for this part. Micron does manufacture 4Gb DDR4 x16 components in comparable FBGA-96 packages (MT40A512M16 class), but pinout and speed-bin verification against the actual Micron datasheet is required before treating any cross-brand part as drop-in.

On the G versus E suffix: both parts are DDR4-3200-class 1.2V devices in the same package; the letter reflects die revision, which can indicate a process node or speed-bin refresh. Treat them as near drop-in equivalents at the PCB level, then confirm final timing parameters against each Samsung datasheet. Against the BCRC: choose the BCWE (G-suffix) for 3200 Mbps designs where bandwidth is a bottleneck; the BCRC suffices for 2666 Mbps systems and may cost less. If doubling capacity is acceptable and your controller's address mapping supports 8Gb densities, the K4A8G165WG-BCWE is physically pin-compatible in the same x16 FBGA-96 footprint - but it will not initialize on controllers that top out at 4Gb row addressing, so check the controller datasheet's supported density table first.

Takeaway: K4A4G165WE-BCWE is the safest pin-to-pin substitute; K4A4G165WE-BCRC is the same-footprint choice for 2666 Mbps designs; avoid cross-brand substitutions without full datasheet verification.

Where Is the K4A4G165WG-BCWE Used in Real Systems?

The verified application set spans six environments, each exploiting a different combination of the part's 4Gb density, x16 organization, 3200 Mbps rate, 19 ns access time, 1.2V supply, and commercial temperature range:

• Embedded computing main memory: the 256M x 16 organization pairs with SoCs exposing 16-bit or 32-bit memory buses, and the 1.2V supply keeps memory power within the typical 5-15W budget of fanless industrial PCs while delivering roughly 25% less power than equivalent DDR3 designs.
• Networking and communication equipment: the 3200 Mbps data rate and 19 ns access time supply the bandwidth network processors need for line-rate forwarding in enterprise switches, routers, and 5G small-cell equipment, with x16 simplifying 16/32-bit NPU and FPGA bus designs.
• Consumer set-top boxes and smart TVs: 4Gbit covers video decode frame buffers, the compact FBGA-96 allows dense placement near the SoC for short matched traces, and the 1.2V rail minimizes standby power for energy-efficiency compliance.
• Industrial control and automation: PLCs, motion controllers, and machine-vision systems use it for runtime data logging, image ring buffers, and firmware execution within the 0C to +85C cabinet environment.
• PC and workstation memory modules: on UDIMMs and SODIMMs, eight 4Gb x16 chips populate a 4GB module on fly-by command/address routing with on-die termination.
• Automotive-adjacent infotainment: aftermarket head units and passenger displays can use its DDR4-3200 bandwidth for 1080p and entry-4K frame buffers - but note this part is not AEC-Q100 qualified, so it is unsuitable for under-hood or safety-critical deployments.

Takeaway: Match the part to commercial-grade environments; step up to an industrial temperature suffix for extended-range applications.

What Should You Budget for the K4A4G165WG-BCWE in 2026?

XAIPART pricing, verified as of 2026-09-23, steps from $23.15 per unit at quantity 1 to $21.50 at 10 units, $19.80 at 100 units, $18.20 at 500 units, and $16.90 at 1000 units. That is roughly a 27% unit-cost reduction from prototype quantities to production volumes. Distributor stock reported in the verified data: LCSC listed 285 pieces (product C49260570) as of 2026-09-01, Wolfchip reported 44,400 pieces (updated August 2026), and DigiKey Marketplace showed buy-now/ships-today status. Lead time for in-stock marketplace quantities is typically 1-3 days; factory-direct orders through Sourcengine offer traceable sourcing with 3-year warranty. DDR4 spot pricing fluctuates with the memory market, so confirm live stock and quotes before committing production schedules. Always verify date codes and traceability when sourcing DDR4 from marketplaces.

Takeaway: Batch at 1000 units for the $16.90 floor price, and lock in traceable, date-coded inventory while multiple distributors hold stock.

Is the K4A4G165WG-BCWE Active and Safe to Design In Long-Term?

The verified lifecycle status is Active - Samsung continues to manufacture the part, and it is listed with active product status in distributor databases. Broad multi-distributor availability (DigiKey Marketplace, LCSC, JLCPCB, Wolfchip, Win Source, Sourcengine) indicates a healthy supply chain as of late 2026. RoHS compliance is confirmed per the JLCPCB listing, and FBGA-packaged Samsung DDR4 devices are supplied lead-free. For REACH, halogen-free, and conflict-minerals documentation, request Samsung's material declaration documents or check the Samsung semiconductor compliance portal before regulatory submission. DDR4 remains the mainstream DRAM generation for embedded and industrial designs, supporting long-term availability expectations, though you should monitor Samsung lifecycle notices through your distributor for formal end-of-life announcements.

Takeaway: Active status plus six-channel distribution makes this a safe design-in today; register for distributor lifecycle notifications to catch any future PCN/EOL early.

What Should DDR4 Buyers Watch Next?

Three things anchored to the verified data. First, speed-bin economics: if your controller runs at DDR4-2666, the same-footprint K4A4G165WE-BCRC may cost less than the 3200 Mbps BCWE part - pay for bandwidth only when the controller can use it. Second, die-revision changes: the G-suffix versus E-suffix distinction shows Samsung refreshes dies within the same footprint; qualify timing per datasheet on any suffix change to avoid controller misconfiguration. Third, sourcing integrity: marketplace stock levels moved materially within weeks in the verified data (285 units at LCSC versus 44,400 at Wolfchip), and DDR4 pricing is market-sensitive - secure traceable, date-coded inventory early in your build cycle rather than relying on spot availability. For extended-temperature needs, plan qualification of an industrial-suffix part rather than stretching the commercial 0C to +85C envelope.

Takeaway: Buy the speed bin your controller actually needs, re-qualify on die-revision changes, and lock traceable stock while availability is broad.

For related DDR4 guidance, see the K4A4G165WF-BCRC complete buyer and design guide, or browse the XAIPART component catalog for additional memory ICs. More component deep dives are available on the XAIPART blog.