K4A4G085WF-BITD - DDR4 4Gb 2666Mbps DRAM | Samsung
MPN: K4A4G085WF-BITD ✓ فعالK4A4G085WF-BITD نمای کلی
DDR4 SDRAM is a synchronous dynamic random-access memory, the successor to DDR3 in the DRAM voltage-regulator-to-memory hierarchy of a computing system. Compared with DDR3, DDR4 lowers operating voltage from 1.5 V to 1.2 V, doubles bank groups for higher bandwidth, and adds features such as DBI (data bus inversion), CA parity, and VPP (2.5 V wordline bootstrap supply), making it the mainstream memory standard for embedded, industrial, and networking processors with DDR4 memory controllers.
Key features of the K4A4G085WF family include 8 internal banks in 4 bank groups, burst lengths of 8 (BL8), on-die termination (ODT), dynamic ODT, write CRC, and optional address parity. The -BITD speed grade codes 2666 Mbps (CL19 typical at 1.2 V), and Samsung's FBGA packaging with fine-pitch ball interconnect supports high-speed signal integrity on 4-layer and higher PCB stacks.
Architecturally, the die uses Samsung's advanced DRAM process with bank-group pipelining, allowing back-to-back data bursts from different bank groups to reach the full 2666 MT/s pin speed. The x8 organization with a single DQ byte lane simplifies controller routing versus x16 parts and enables ECC via read-modify-write on boards that populate multiple x8 devices.
Typical applications include industrial embedded controllers, networking switches and routers, security/surveillance systems, test and measurement instruments, and edge computing gateways where the -40C to +95C industrial temperature rating is required.
Design consideration: DDR4 requires precise 2400-ohm-class ODT tuning and length-matched fly-by routing of clock/address/command lines; ensure your processor's memory controller reference design supports the -BITD CL19 timing set at 2666 MT/s.
This page synthesizes distributor pricing, drop-in alternatives, and practical DDR4 design notes not found in the manufacturer datasheet.
جایگزین‌های drop-in برای K4A4G085WF-BITD — همان پکیج، سازگار پین‌به‌پین. قطعات با پکیج متفاوت که نیاز به تغییر PCB دارند مستثنی هستند.
گونه‌ها در این سری
مدل‌های هم‌سری که جایگزین مستقیم هستند برای K4A4G085WF-BITD (همان فرم‌فاکتور و فوت‌پرینت) — متفاوت در Package, Interface, Memory Type, Data Rate, Mounting Type.
K4A4G085WF-BCWE
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
K4A4G085WD-BCRC
✅ جایگزین مستقیم ⚠️ مشخصات تأییدنشدهبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←K4A4G085WG-BCWE
✅ جایگزین مستقیم ⚠️ مشخصات تأییدنشدهبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←MT40A512M8RH-075E:B
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←K4A4G085WF-BITD مشخصات
| نوع حافظه | DDR4 SDRAM |
| Density | 4 Gbit |
| سازمان | 512M x 8 |
| Speed | 2666 Mbps (MT/s) |
| Supply Voltage (VDD) | 1.2 V |
| VPP Voltage | 2.5 V |
| دمای کاری | -40C to +95C |
| بسته‌بندی | 78-ball FBGA (78FBGA) |
| Bank Architecture | 8 banks x 4 bank groups |
| Burst Length | BL8 |
| تأخیر CAS | CL19 (typical at 2666 Mbps) |
| نوع نصب | Surface Mount (BGA) |
| رابط | Parallel, DDR4 SSTL12 |
| Refresh | Self-refresh and auto-refresh (8K/64ms per JEDEC DDR4) |
| Termination | ODT / dynamic ODT |
| Data Mask | DM supported (x8) |
| Application Grade | Industrial |
راهنمای پیکربندی پین K4A4G085WF-BITD 78-ball fbga (78fbga)
پیکربندی پین برای K4A4G085WF-BITD (پکیج 78-ball fbga (78fbga)). شماره‌گذاری پایه‌ها، عملکردها و نمودارهای اتصال در دیتاشیت سازنده تعریف شده است. برای footprint دقیق و دستورالعمل‌های لحیم‌کاری به آن مراجعه کنید.
داده پین‌آوت تفصیلی موجود نیست برای K4A4G085WF-BITD.
به دیتاشیت برای پیکربندی کامل پین‌ها.
کاربردهای معمول
K4A4G085WF-BITD مناسب است برای 6 کاربردs: Industrial Embedded Controllers, Networking Switches and Routers, Security and Surveillance Systems, Test and Measurement Instruments, Edge Computing Gateways, Automotive-Adjacent Telematics and Display Units.
Industrial Embedded Controllers
Industrial PLCs and embedded controllers benefit directly from the K4A4G085WF-BITD's -40C to +95C operating range, which covers cold-start in unheated cabinets and sustained 85C+ ambient near power electronics. Its 4 Gb density and 512M x 8 organization provide ample buffer space for protocol stacks and motion-control data, while the 2666 Mbps rate at 1.2 V keeps memory power low enough for passively cooled enclosures. Implemented as one or more x8 DDR4 components on the controller's JEDEC-standard 78-ball FBGA footprint, the device supports ODT and write CRC for signal integrity in electrically noisy factory environments, and the x8 lane simplifies length-matched routing on cost-sensitive 4-6 layer boards.
پیشنهادی
Networking Switches and Routers
Enterprise and industrial networking equipment requires high packet-buffer bandwidth, and the K4A4G085WF-BITD's 2666 Mbps pin speed with 4 bank groups enables interleaved accesses that sustain the throughput demanded by lookup tables, queue buffers, and statistics counters. The 512M x 8 organization with BL8 bursts aligns efficiently with typical 64-256 byte cacheline traffic, and write CRC improves data reliability on the write path at full speed. Multiple x8 devices can be combined with one additional x8 for side-band ECC, satisfying the error-rate budgets of carrier-grade platforms while keeping the 1.2 V rail efficient in always-on 24/7 operation.
پیشنهادی
Security and Surveillance Systems
IP cameras and NVR front ends need buffering for multi-stream video capture, and the K4A4G085WF-BITD's 4 Gb capacity stores multiple 1080p frame pipelines while its 2666 Mbps bandwidth sustains simultaneous capture and encode read-back. The -40C to +95C rating is essential for pole-mounted and outdoor housings that experience full solar load and sub-zero winters. At 1.2 V, the DRAM contributes a small share of the tight thermal budget of fanless camera enclosures, and Samsung's dynamic ODT helps maintain signal integrity on the short, low-cost PCB traces typical of camera modules.
پیشنهادی
Test and Measurement Instruments
Oscilloscopes, logic analyzers, and data acquisition systems use DRAM as deep capture memory, where the K4A4G085WF-BITD's 4 Gb density extends record length and its 2666 Mbps rate keeps up with high-speed ADC data streams after FIFO decimation. The x8 data path simplifies interleaving multiple devices into wide capture buses, and 4 bank groups allow the controller to hide tRCD latency across interleaved sample blocks. Industrial temperature rating supports benchtop and portable instruments used in non-conditioned environments, while the 1.2 V rail reduces internal heating that would otherwise degrade precision analog references.
پیشنهادی
Edge Computing Gateways
IoT and edge AI gateways running Linux require hundreds of megabytes of working memory; the K4A4G085WF-BITD provides 512 MB per device, and two devices reach 1 GB of 64-bit-plus-ECC memory. Its 2666 Mbps rate feeds both general-purpose workloads and small neural inference models, while DDR4's 1.2 V operation reduces total system power versus DDR3 solutions, extending thermal headroom in sealed gateway enclosures. The industrial -40C to +95C range and ODT-based signal integrity make it reliable on gateway boards with mixed digital/RF routing, and write CRC adds data-path protection for fleet-deployed units.
پیشنهادی
Automotive-Adjacent Telematics and Display Units
Non-safety telematics, digital clusters, and infotainment-adjacent modules use DDR4 for graphics buffering and application memory. While the K4A4G085WF-BITD is an industrial-grade part rather than AEC-Q100 automotive memory, its -40C to +95C rating matches many under-dash ambient profiles, and its 4 Gb density supports map rendering and 2D/3D graphics layers. Designers should evaluate the Samsung automotive-qualified DDR4 lines for safety-relevant applications, but for cost-driven commercial-vehicle accessories and aftermarket units, this component delivers 2666 Mbps bandwidth at low 1.2 V power with a JEDEC-standard footprint that eases second-sourcing.
پیشنهادی
خلاصه محصولات پیشنهادی
داده‌های مرجع مهندسی برای K4A4G085WF-BITD — مقایسه، راهنمای طراحی و اطلاعات انطباق.
راهنمای انتخاب
مقایسه با جایگزین‌ها
| پارامتر | این محصول | K4A4G085WF-BCWE | K4A4G085WD-BCRC | K4A4G085WG-BCWE | MT40A512M8RH-075E:B |
|---|---|---|---|---|---|
| Package | 78-ball FBGA | 78-ball FBGA - same | 78-ball FBGA - same | 78-ball FBGA - same | 78-ball FBGA - same (JEDEC ballout) |
| Brand | Samsung Electronics | Samsung Electronics | Samsung Electronics | Samsung Electronics | Micron Technology |
| Density | 4 Gbit | 4 Gbit | 4 Gbit | 4 Gbit | 4 Gbit |
| Organization | 512M x 8 | 512M x 8 | 512M x 8 | 512M x 8 | 512M x 8 |
| Speed Grade | 2666 Mbps | 3200 Mbps | 2666 Mbps class | 3200 Mbps | DDR4-2666 class (-075) |
| Supply Voltage | 1.2 V | 1.2 V | 1.2 V | 1.2 V | 1.2 V |
تفاوت‌های کلیدی
- Industrial temperature rating at commodity DDR4 cost (در مقابلMT40A512M8RH-075E:B)
- Speed-grade flexibility within the same footprint (در مقابلK4A4G085WF-BCWE)
- JEDEC-standard x8 ballout enables true multi-vendor drop-in (در مقابلK4A4G085WD-BCRC)
یادداشت‌های طراحی
Route the DDR4 fly-by topology for clock, address, and command lines with controlled impedance (40-50 ohm single-ended) and place the series termination resistor at the far end of the chain per the processor's memory design guide. Length-match DQ/DQS/DM groups within +/-25 mils intra-byte-lane; the x8 organization means one DQS pair serves DQ0-DQ7, which is more forgiving than x16 layouts. Reference VDDQ planes for all DDR4 signals and return CA/CK signals on a continuous VDD plane to avoid reference splits under the 78FBGA.
Provide two regulated rails: VDD/VDDQ at 1.2 V and VPP at 2.5 V. A point-of-load buck converter such as the TI TPS54218 family can supply the 1.2 V rail; size it for the sum of IDD0/IDD4R/IDD4W currents at 2666 MT/s from the Samsung datasheet IDD tables. Add bulk (22-47 uF) plus per-device 100 nF/10 nF decoupling capacitors immediately under the FBGA ball field via micro-vias. Do not omit VPP - it powers wordline charge pumps, and floating it can prevent initialization.
Three frequent DDR4 bring-up failures: (1) RESET# must be actively driven low during power-up - leaving it floating causes undefined state; sequence per JEDEC: VDD/VDDQ before RESET# release, CKE low until after RESET# deassert. (2) ODT settings must match the board topology; incorrect Rtt_NOM/Rtt_WR values cause read eye closure that mimics timing errors. (3) Industrial temperature operation above 85C requires a 2x refresh multiplier in the controller configuration - omitting it causes intermittent bit errors at high ambient.
Enable write CRC for data reliability at 2666 Mbps on longer traces, and use the controller's read/write leveling (DQS gating and write leveling) during bring-up to compensate for PCB skew. On 4-layer boards, keep DDR4 trace lengths under approximately 75 mm where possible; estimate flight-time skew budget as: propagation ~150 ps/inch FR-4, so a 3-inch trace adds ~450 ps against a ~750 ps UI at 2666 Mbps, leaving margin only with correct on-die termination.
اطلاعات انطباق
RoHS/lead-free status inferred from current Samsung production DDR4 policy; REACH, halogen-free, and conflict-minerals declarations were not present in the provided web data and should be confirmed via Samsung's official product compliance documentation.
