HM628128LP-8 - 128K x 8 85ns CMOS SRAM | Renesas
MPN: HM628128LP-8 ✗ انتهى عمره الإنتاجيHM628128LP-8 نظرة عامة
Static random-access memory, or SRAM, is a volatile semiconductor memory category that stores each bit as a latch state and therefore does not require periodic refresh. A parallel SRAM belongs to the broader hierarchy of semiconductor memory, alongside ROM, DRAM, flash memory, and other volatile or nonvolatile storage. The HM628128LP-8 is positioned for systems requiring deterministic access, direct bus interfacing, and byte-wide memory rather than the high density or serial interface of more specialized memory devices.
Its principal specifications include a 131072-word by 8-bit organization, an 85 ns rated access time, CMOS technology, and a 32-pin plastic DIP package. The 0.8 μm Hi-CMOS implementation supports the device's stated combination of density, performance, and low power consumption. Because the memory is organized for eight-bit parallel operation, the associated system bus must present and latch eight data lines for each addressed word.
In a typical processor or controller system, the SRAM provides temporary storage for variables, buffers, stack or working memory, and intermediate data that must be accessed rapidly. Its parallel architecture simplifies connection to older microprocessor and embedded-controller buses, while the 85 ns timing provides a defined maximum access interval for synchronous memory-control logic. Exact address timing, setup requirements, and power-state limits should be implemented according to the manufacturer datasheet.
Typical uses include industrial control systems, legacy embedded platforms, data-acquisition equipment, communication modules, and compact controller boards that retain a parallel SRAM interface. It can also serve as expansion memory when a controller lacks sufficient internal RAM. Selection should account for package footprint, bus width, access timing, supply voltage, and signal levels, because memory components with the same storage capacity are not necessarily interchangeable.
The most important PCB-design issue is preserving signal integrity across the address, data, and control lines. Place the device close to the memory controller when possible, route the bus systematically, and decouple each supply connection near the package. Because this is a legacy PDIP device intended for through-hole assembly, designers should also verify board spacing, pin orientation, and any daughter-card or socket constraints before committing the footprint.
This product page combines the published memory organization, access time, technology, and package information with drop-in replacement analysis, application guidance, comparison parameters, and practical integration notes. It is intended to help engineers determine whether HM628128LP-8 fits an existing parallel-memory design and what must be checked before substitution or PCB reuse.
بدائل مباشرة لـ HM628128LP-8 — نفس الحزمة، متوافق دبوس بدبوس. تُستثنى القطع ذات الحزم المختلفة التي تتطلب تعديل PCB.
HM628128LP-10
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
HM628128BLP-8
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
HM628128LP-8SL
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
HM628128LP-8 الحدود القصوى والخصائص الكهربائية
| نوع الذاكرة | High-speed CMOS static RAM (SRAM) |
| Memory Organization | 131072 word x 8 bit |
| Storage Capacity | 1,048,576 bit (131,072 bytes) |
| عرض ناقل البيانات | 8 bit |
| Access Time | 85 ns |
| Process Technology | 0.8 μm Hi-CMOS |
| Technology | CMOS |
| العلبة | PDIP-32, 0.600 inch |
| عدد الأطراف | 32 pins |
| نوع التركيب | Through-hole |
| Nonvolatile Storage | No, volatile memory |
| Refresh Requirement | No refresh required |
دليل تكوين أطراف HM628128LP-8 pdip-32, 0.600 inch
تكوين الأطراف لـ HM628128LP-8 (حزمة pdip-32, 0.600 inch). تتضمن هذه الدائرة المتكاملة الرقمية GPIO وواجهات الاتصال (UART وSPI وI2C) وأطراف الطاقة. راجع ورقة بيانات الشركة المصنعة لوظائف الأطراف البديلة وخيارات التكوين. ضرورية لتصميم الأنظمة المدمجة وتخطيط PCB.
لا تتوفر بيانات مفصلة لمخطط التوصيلات لـ HM628128LP-8.
راجع ورقة البيانات للحصول على تكوين الأطراف الكامل.
التطبيقات النموذجية
HM628128LP-8 مناسب لـ 6 التطبيقs: Industrial Controller Memory Expansion, Legacy Embedded System SRAM, Data Acquisition Buffer Memory, Communication Gateway Buffer, Test and Measurement Instrument Memory, Retrofit and Obsolescence Recovery.
Industrial Controller Memory Expansion
The HM628128LP-8 suits legacy industrial controllers that require additional working memory but retain a parallel processor bus. Its 131072 x 8 organization provides 131,072 bytes, while the eight-bit interface can connect directly to an eight-bit address and data bus with external chip-select decoding. The 85 ns access rating supports established controller timing schemes, but system designers should verify the processor bus cycle, address setup, chip-select delay, and supply voltage against the manufacturer timing diagram. Through-hole PDIP construction also suits backplanes and control boards where socketed or leaded memory is preferable.
موصى به
Legacy Embedded System SRAM
HM628128LP-8 is appropriate for a legacy embedded platform whose memory bus was designed around a 128K x 8 parallel SRAM. The device adds 131,072 bytes of volatile storage for buffers, variables, stack space, or intermediate results without introducing the serial protocol and command overhead of a serial memory. Its 85 ns access time provides a defined timing target, but the complete interface must preserve address, data, chip-select, output-enable, and write-enable requirements. Before replacing an original device, compare every electrical characteristic and the full 32-pin termination pattern.
موصى به
Data Acquisition Buffer Memory
The HM628128LP-8 can provide a parallel temporary buffer in a data-acquisition controller that collects samples in a time-critical acquisition path. Its 128K x 8 organization can hold substantial byte-oriented data, and the 85 ns access time permits deterministic reads and writes when connected to suitable address and control logic. Designers should account for bus contention, propagation delay, output-enable behavior, and any FIFO or DMA transfer overhead. The volatile memory should also be paired with an appropriate retention strategy when acquired data must survive a power interruption.
موصى به
Communication Gateway Buffer
A communication gateway can use HM628128LP-8 as a parallel working-memory buffer between a legacy host processor and slower peripheral logic. The 131,072-byte capacity is useful for packet staging, protocol translation buffers, and temporary message queues, while the eight-bit organization matches many processor buses of the same generation. Integration requires deliberate address decoding and bus arbitration so the SRAM and other memory-mapped peripherals do not drive the data lines simultaneously. Timing analysis should include address-decode delay in addition to the SRAM's 85 ns access time.
موصى به
Test and Measurement Instrument Memory
The HM628128LP-8 can support sample, trace, or configuration storage in a legacy test instrument that uses a processor-controlled parallel memory bus. Its 128K x 8 format can hold byte-oriented measurement records, while 85 ns access timing supports deterministic operations such as trace retrieval and menu or parameter handling. For high-speed acquisition, separate buffering and transfer hardware may still be necessary because memory-access time alone does not determine complete system throughput. Validate signal integrity, grounding, decoupling, and write timing on the target motherboard.
موصى به
Retrofit and Obsolescence Recovery
HM628128LP-8 is particularly relevant when maintaining an older machine, controller, or embedded instrument whose original parallel SRAM is no longer readily available. Because the part is identified as a 32-pin PDIP device, it can support socketed or through-hole repair strategies when the board layout, supply voltage, and timing are unchanged. Replacement work should include a complete pin-level comparison, a bus-cycle timing check, and thermal inspection of surrounding components. A substitution should not be accepted solely because its capacity and package shape match; data-bus, control, and voltage compatibility remain essential.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ HM628128LP-8 — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | HM628128LP-10 | HM628128BLP-8 | HM628128LP-8SL |
|---|---|---|---|---|
| Package | PDIP-32 | PDIP-32 | PDIP-32 | PDIP-32 |
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Memory Organization | 131072 word x 8 bit | 131072 word x 8 bit | 128K x 8 bit | 128K x 8 bit |
| Memory Type | CMOS static RAM | CMOS static RAM | CMOS static RAM | CMOS static RAM |
| Data Bus Width | 8 bit | 8 bit | 8 bit | 8 bit |
| Mounting Type | Through-hole PDIP | Through-hole PDIP | Through-hole PDIP | Through-hole PDIP |
أبرز الفروقات
- Faster access rating within the documented HM628128 family (مقابلHM628128LP-10)
- Original 85 ns timing grade preserves existing design assumptions (مقابلHM628128BLP-8)
- Matches the core 128K x 8 CMOS and PDIP32 system interface (مقابلHM628128LP-8SL)
ملاحظات التصميم
Treat the address, data, chip-select, output-enable, and write-enable paths as one synchronous memory interface. The 85 ns access specification does not include decoding, logic, or board-propagation delay. Check address setup and hold requirements against the controller timing, ensure only one device can assert the bus, and place the SRAM close to the controller when the PCB supports a short, orderly memory route.
Before assigning a board footprint, compare the complete 32-pin termination and row spacing against the original component rather than relying only on the PDIP-32 label. Through-hole sockets, machine sockets, and soldered footprints can differ in mechanical details. Confirm pin-one orientation, body width, lead pitch, and clearance around adjacent components. The published product information identifies a 0.600-inch PDIP package but does not provide a complete mechanical drawing.
Use the manufacturer-specified supply limits and power-consumption limits when designing the memory rail and bypass network. SRAM read and write activity can change current demand, so decouple the supply close to the package and provide a stable return path. Because the exact operating-voltage and current values are not reproduced in the product summary, consult the manufacturer electrical-characteristics table before selecting regulators or bulk capacitance.
Do not approve a replacement based only on matching 128K x 8 capacity and a 32-pin DIP outline. Verify address-line count, chip-select polarity, output-enable polarity, write-enable polarity, supply voltage, standby behavior, access time, and timing margins. In particular, HM628128LP-10 changes the access time from 85 ns to 100 ns, which can alter the maximum operating frequency of a marginal design.
معلومات الامتثال
This legacy SRAM is not presented as an AEC-Q100 automotive-qualified device. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status were not established in the referenced product information and therefore remain unknown.
