K4S281632F-TC75 - 128Mb F-die SDRAM 8Mx16 TSOP-54 | Samsung
MPN: K4S281632F-TC75 ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.95 | $8.95 |
| 10 | $8.05 | $80.50 |
| 100 | $7.2 | $720.00 |
| 500 | $6.55 | $3,275.00 |
| 1,000 | $5.9 | $5,900.00 |
K4S281632F-TC75 Overview
A Synchronous DRAM (SDRAM) is a type of dynamic random-access memory that adds a separate clock signal to coordinate data I/O on the rising edge, eliminating the asynchronous timing constraints of earlier FPM/EDO DRAM. SDRAM sits in the memory hierarchy between bulk storage (NAND flash, HDD) and CPU registers, and 128Mb-class parts like the K4S281632F-TC75 historically populated main memory of embedded systems, set-top boxes, networking line cards, printers, and industrial controllers throughout the 2000s before being superseded by DDR, DDR2 and Mobile SDRAM/LPDDR generations.
Key features of the K4S281632F-TC75 include dual-bank architecture (2 banks selectable via BA0), programmable CAS Latency (CL = 2 or 3), programmable Burst Length (1, 2, 4, 8, full page), Auto-Refresh and Self-Refresh modes, LVTTL-compatible I/O, and a 64 ms refresh interval distributed across 4K refresh cycles. The 16-bit data bus and on-chip burst counter simplify glue-less connection to 16/32-bit microprocessors and ASICs.
Internally, the die uses Samsung's F-die 0.13 nm-class process node and a 2-bit prefetch architecture (later generations would migrate to 4-bit prefetch with DDR). Row address is 12 bits (A0-A11) and column address is 8 bits (A0-A7) multiplexed on the same pins, with /RAS, /CAS, /WE, and /CS providing the standard SDRAM command set. The TSOP-II 54-pin form factor is the industry-standard footprint for 128 Mb x16 SDRAM, allowing board-level replacement of similar Micron, Hynix and Qimonda parts.
Typical applications for the K4S281632F-TC75 include main working memory in legacy embedded CPU boards (e.g., ARM7/ARM9 SBCs, PowerQUICC), graphics frame buffers, network switch control planes, point-of-sale terminals, automotive infotainment pre-DDR3, and other cost-optimized commercial or industrial designs where supply voltages below 2.5 V are not required. The part remains in demand today for maintenance, repair and legacy OEM replacements.
A critical design consideration is the 3.3 V supply requirement: most modern systems use 1.8 V DDR1 or 1.5 V/1.35 V DDR2/3, so the K4S281632F-TC75 cannot be retrofitted to those without a level translator. Always honor the 200 us power-on initialization sequence and the minimum 200 us wait after a CKE rise before issuing the LOAD MODE REGISTER command.
This page synthesizes distributor pricing, drop-in alternatives from Samsung and competing SDRAM vendors, and practical design notes not found in a single Samsung datasheet, providing engineers with everything needed to qualify, source, and design with the K4S281632F-TC75.
Drop-in alternatives for K4S281632F-TC75 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
K4S281632F-TC1L
✅ Drop-In📋 Reference alternative (not in catalog)
MT48LC8M16A2P-75
✅ Drop-In📋 Reference alternative (not in catalog)
MT48LC8M16A2TG-75
✅ Drop-In📋 Reference alternative (not in catalog)
HY57V651620B-H
✅ Drop-In📋 Reference alternative (not in catalog)
W981616CH-75
✅ Drop-In📋 Reference alternative (not in catalog)
K4S281632F-TC75 Maximum Ratings & Electrical Characteristics
| Memory Type | Synchronous DRAM (SDRAM) |
| Memory Density | 128 Mb (16 MB) |
| Organization | 8M words x 16 bits |
| Number of Banks | 2 |
| Supply Voltage (VDD/VDDQ) | 3.3 V (typ) |
| Clock Frequency | 133 MHz (max, CL=3) |
| Clock Period (tCK) | 7.5 ns |
| Speed Grade | -TC75 |
| CAS Latency | Programmable, 2 or 3 |
| Burst Length | 1, 2, 4, 8, full page |
| Refresh Interval | 64 ms |
| Refresh Cycles | 4K (4096) |
| Interface | LVTTL |
| Process Node | Samsung F-die |
| Package | TSOP-II 54 (Type II), 0.80 mm pitch |
| Mounting Type | Surface Mount |
K4S281632F-TC75 Pin Configuration
| Pin 1 | VDD — Power supply (3.3 V) |
| Pin 2 | DQ0 — Data I/O line 0 |
| Pin 3 | DQ1 — Data I/O line 1 |
| Pin 4 | DQ2 — Data I/O line 2 |
| Pin 5 | DQ3 — Data I/O line 3 |
| Pin 6 | VDDQ — I/O power supply (3.3 V) |
| Pin 7 | DQ4 — Data I/O line 4 |
| Pin 8 | DQ5 — Data I/O line 5 |
| Pin 9 | DQ6 — Data I/O line 6 |
| Pin 10 | DQ7 — Data I/O line 7 |
| Pin 11 | DQ8 — Data I/O line 8 |
| Pin 12 | VSSQ — I/O ground |
| Pin 13 | DQ9 — Data I/O line 9 |
| Pin 14 | DQ10 — Data I/O line 10 |
| Pin 15 | DQ11 — Data I/O line 11 |
| Pin 16 | DQ12 — Data I/O line 12 |
| Pin 17 | DQ13 — Data I/O line 13 |
| Pin 18 | DQ14 — Data I/O line 14 |
| Pin 19 | DQ15 — Data I/O line 15 |
| Pin 20 | VSS — Ground |
| Pin 21 | DQML — Lower byte data mask (DQML = /LDQM) |
| Pin 22 | /WE — Write enable (active low) |
| Pin 23 | /CAS — Column address strobe (active low) |
| Pin 24 | /RAS — Row address strobe (active low) |
| Pin 25 | /CS — Chip select (active low) |
| Pin 26 | BA0 — Bank address 0 |
| Pin 27 | A11 — Address bit 11 |
| Pin 28 | A10 — Address bit 10 / Auto-Precharge |
| Pin 29 | A0 — Address bit 0 |
| Pin 30 | A1 — Address bit 1 |
| Pin 31 | A2 — Address bit 2 |
| Pin 32 | A3 — Address bit 3 |
| Pin 33 | VDD — Power supply (3.3 V) |
| Pin 34 | VSS — Ground |
| Pin 35 | A4 — Address bit 4 |
| Pin 36 | A5 — Address bit 5 |
| Pin 37 | A6 — Address bit 6 |
| Pin 38 | A7 — Address bit 7 |
| Pin 39 | A8 — Address bit 8 |
| Pin 40 | A9 — Address bit 9 |
| Pin 41 | NC — Not connected (per JEDEC) |
| Pin 42 | CKE — Clock enable |
| Pin 43 | CLK — Clock input |
| Pin 44 | DQMH — Upper byte data mask (DQMH = /UDQM) |
| Pin 45 | VSS — Ground |
| Pin 46 | VSS — Ground |
| Pin 47 | VDD — Power supply (3.3 V) |
| Pin 48 | VSS — Ground |
| Pin 49 | NC — Not connected (per JEDEC) |
| Pin 50 | NC — Not connected (per JEDEC) |
| Pin 51 | NC — Not connected (per JEDEC) |
| Pin 52 | NC — Not connected (per JEDEC) |
| Pin 53 | NC — Not connected (per JEDEC) |
| Pin 54 | NC — Not connected (per JEDEC) |
Typical Applications
K4S281632F-TC75 is suitable for 6 applications: Legacy Embedded SBC Main Memory, Set-Top Box & Digital TV Buffer Memory, Network Switch / Router Control Plane, POS Terminal Main Memory, Industrial Printer / Copier Buffers, Automotive Infotainment (Pre-DDR3).
Legacy Embedded SBC Main Memory
The K4S281632F-TC75's 128 Mb density and 8M x16 organization are ideally matched to legacy embedded single-board computers built around ARM7/ARM9, MIPS, or PowerPC cores with native SDRAM controllers. Its 16-bit data bus glues directly to 16/32-bit CPU external memory interfaces, providing 16 MB of working memory - sufficient for embedded Linux distributions, RTOS kernels, and application code in industrial SBC designs. The -TC75 speed grade's 7.5 ns clock period supports 133 MHz operation, which is the maximum clock rate of most legacy SDRAM controllers (e.g., Samsung S3C2410, Freescale MPC860). Unlike LPDDR, the 3.3 V supply rails directly from the same regulator powering the host CPU core, simplifying power design. The 64 ms refresh requirement is handled automatically by the on-chip refresh counter, freeing the controller to perform other tasks. Engineers should observe the 200 us power-on stabilization before issuing MODE REGISTER SET commands.
Recommended
Set-Top Box & Digital TV Buffer Memory
Set-top boxes and digital TVs from the 2003-2008 generation used 128 Mb x16 SDRAM as main working memory and graphics frame buffers before the industry migrated to DDR. The K4S281632F-TC75 provides the bandwidth needed for MPEG-2 decoding at standard-definition resolutions and basic on-screen-display graphics. Its 2-bank architecture allows one bank to refresh while the other services video DMA, minimizing display tearing. The 16-bit data bus pairs naturally with MPEG decoder ASICs that natively accept 16-bit SDRAM, simplifying board layout. With 3.3 V I/O, the part interfaces directly to the analog video encoder without additional level shifting. Designers should allocate two banks of memory (32 MB total) for 720p progressive video, or pair with a second K4S281632F-TC75 chip-select for 32 MB.
Recommended
Network Switch / Router Control Plane
Network switches and routers in the 2000s used 128 Mb SDRAM for control-plane memory: routing tables, packet buffers, and exception queues. The K4S281632F-TC75's 128 Mb density supports 16 MB of control memory on most enterprise switch platforms of that era. Its full-page burst mode allows efficient DMA transfers when the network processor writes or reads packet headers. With 64 ms refresh and a 4K-cycle refresh counter, the part maintains data integrity during long idle periods typical of control-plane operations. The TSOP-II 54 package is widely supported on legacy networking ASICs (e.g., Broadcom BCM series, Vitesse switches) with native SDRAM controllers. Engineers should note that newer control-plane designs migrate to DDR2/DDR3 for higher bandwidth, but the K4S281632F-TC75 remains in demand for maintenance of installed equipment.
Recommended
POS Terminal Main Memory
Point-of-sale (POS) terminals, especially those deployed in the 2000s, used 128 Mb SDRAM like the K4S281632F-TC75 as the main working memory for transaction-handling firmware, encryption key storage, and print buffers. The 16 MB density is sufficient for the embedded application code plus transaction database caching typical of these systems. The -TC75 speed grade's 133 MHz peak operation handles encryption accelerator burst writes without contention. Commercial temperature range makes the part suitable for indoor retail environments. Because POS systems are deployed for 7-10 years and require long-term parts availability, the K4S281632F-TC75's last-time-buy status is a concern, and engineers should plan qualification of cross-brand equivalents like MT48LC8M16A2P-75 to ensure service support.
Recommended
Industrial Printer / Copier Buffers
Industrial printers and copiers use 128 Mb SDRAM to buffer rasterized print data between the formatter ASIC and the print engine, ensuring continuous paper feed without under-run. The K4S281632F-TC75's 8M x16 organization provides ample buffer space for letter-size 600 dpi raster images, and the 2-bank architecture lets the formatter write to one bank while the engine reads from the other, maximizing throughput. The TSOP-II 54 footprint simplifies board rework during field service. Engineers designing new printer controllers typically choose DDR or LPDDR for higher bandwidth, but the K4S281632F-TC75 remains relevant for legacy formatter ASICs and as a buffer for low-cost monochrome printers. Pair two devices in chip-select mode for 32 MB buffer space suitable for color A4 print at 1200 dpi.
Recommended
Automotive Infotainment (Pre-DDR3)
First-generation automotive infotainment head units and rear-seat entertainment systems used 128 Mb SDRAM like the K4S281632F-TC75 for OS working memory and audio/video buffer. The 3.3 V supply rails conveniently from the vehicle's 12 V bus through simple LDOs. The part's synchronous interface is natively supported by the SH-4, MIPS, and ARM-based automotive SoCs of that era. Note that the -TC75 is the commercial temperature grade; for under-hood or cabin-temperature-extreme applications, an industrial-grade variant (suffix 'I') is required, which should be sourced from cross-vendor equivalents if the K4S281632F-TC75 industrial variant is not available. Designers should note that current automotive designs have migrated to LPDDR4/DDR4 with stricter AEC-Q100 qualification.
Recommended
Recommended Products Summary
Engineering reference data for K4S281632F-TC75 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | K4S281632F-TC1L | MT48LC8M16A2P-75 | MT48LC8M16A2TG-75 | HY57V651620B-H | W981616CH-75 |
|---|---|---|---|---|---|---|
| Brand | Samsung Electronics | Samsung Electronics | Micron Technology | Micron Technology | SK Hynix | Winbond |
| Package | TSOP-II 54 (0.80 mm pitch) | TSOP-II 54 - same | TSOP-II 54 - same | TSOP-II 54 - same | TSOP-II 54 - same | TSOP-II 54 - same |
| Memory Density | 128 Mb (16 MB) | 128 Mb | 128 Mb | 128 Mb | 128 Mb | 128 Mb |
| Organization | 8M x 16 | 8M x 16 | 8M x 16 | 8M x 16 | 8M x 16 | 8M x 16 |
| Supply Voltage | 3.3 V | 3.3 V | 3.3 V | 3.3 V | 3.3 V | 3.3 V |
| Clock Period (tCK) | 7.5 ns | 7.5 ns | 7.5 ns | 7.5 ns | 7.5 ns | 7.5 ns |
| Max Operating Frequency | 133 MHz | 133 MHz | 133 MHz | 133 MHz | 133 MHz | 133 MHz |
Key Differentiators
- Original Samsung F-die, broadest distributor availability (vs MT48LC8M16A2P-75 (Micron))
- 7.5 ns speed grade supports 133 MHz at full CL=3 timing (vs K4S281632F-TC1L (Samsung low-power variant))
- TSOP-II 54 is JEDEC standard 128Mb x16 footprint (vs K4S281632F-UC75 (uBGA package))
Design Notes
The K4S281632F-TC75 requires a stable 3.3 V supply on both VDD and VDDQ rails with a tolerance of +/- 0.3 V per the Samsung datasheet. Decouple each rail with a 0.1 uF ceramic capacitor placed within 5 mm of each VDD/VDDQ pin, plus a single 10 uF bulk capacitor at the supply entry point. Power-on sequencing is not required between VDD and VDDQ, but both must reach 90% of nominal within 200 us before the controller may begin clocking the part. Designers should budget approximately 100 mA active current and 2 mA standby (CKE low) per device. Multiple K4S281632F-TC75 devices in chip-select mode should be fed from a regulator capable of supplying total active current with at least 25% headroom for transient peaks during row activation.
Use a 4-layer PCB with continuous ground and power planes for the K4S281632F-TC75. Route all 16 DQ lines in matched-length groups (matching within +/- 0.5 cm / 25 ps) to maintain the SDRAM tDQHs setup/hold window. Clock (CLK) and CKE traces should be 50 ohm controlled-impedance, routed away from DQ lines to minimize crosstalk. Place the SDRAM no more than 5 cm from the host controller to keep round-trip delays within the 7.5 ns clock period. Decoupling: 0.1 uF X7R ceramic on each VDD/VDDQ pair, plus a 10 uF bulk capacitor per device. Matched impedance for CLK is essential at 133 MHz; a 4-layer stack with 0.2 mm dielectric on the signal layer is typical.
Three common pitfalls when designing with the K4S281632F-TC75: (1) Failing to honor the 200 us power-on wait before MODE REGISTER SET - the JEDEC SDRAM spec requires this, and skipping it can cause undefined behavior or non-volatile register corruption. (2) Exceeding the maximum 7.5 ns tCK at CL=2 versus CL=3 - check the AC timing table carefully; at CL=2 the minimum tCK is longer, so the part may not reach 133 MHz. (3) Forgetting DQML/DQMH masking - these are byte-wise data masks, not byte enables; failure to assert them properly during partial writes causes data corruption on the unselected byte. Always reference the latest Samsung datasheet revision and the JEDEC JESD21-C SDRAM standard for definitive timing.
Compliance Information
RoHS/REACH compliance for the K4S281632F-TC75 must be verified from Samsung's official product page or a current Declaration of Conformity letter from the distributor - the third-party datasheet aggregators do not certify compliance status. The Samsung SDRAM family was offered in both leaded and lead-free finish variants; the exact reel must be verified before shipping to EU markets. AEC-Q100 qualification is not applicable for a commercial-grade memory IC; automotive applications should source industrial-temperature-grade parts from cross-vendor equivalents.
