Infineon Technologies S27KL0643DPBHI020

Overview

S27KL0643DPBHI020 from Infineon is a 64Mb self-refresh DRAM (PSRAM) with octal xSPI interface, supporting 1.8 V/3.0 V I/O and core supplies, 200 MHz DDR clock, 400 MBps data throughput, and industrial temperature range (–40°C to +85°C). It functions as a high-bandwidth, low-pin-count external memory buffer in microcontroller-based edge AI inference accelerators.

For engineers reviewing the S27KL0643DPBHI020 datasheet, S27KL0643DPBHI020 pinout, S27KL0643DPBHI020 application, or S27KL0643DPBHI020 equivalent, key selection criteria include xSPI octal DDR timing compliance, RWDS strobe behavior during read/write, configurable burst lengths (16–128 bytes), hybrid sleep power mode, and FBGA-24 package compatibility with high-density PCB layouts.

Technical Context

This PSRAM integrates on-die refresh control logic that autonomously manages DRAM array refresh without host intervention, presenting static RAM-like behavior to the xSPI master. Its octal DDR interface uses CK and RWDS for precise data capture timing, with optional differential CK#/CK and DCARS phase-shifted strobe support.

The device implements command-based transactions with 16-bit opcodes (dual 8-bit sent on both CK edges), supports linear/wrapped/hybrid burst modes, and provides partial array refresh (1/8, 1/4, 1/2) alongside full refresh - all managed via internal state machine independent of host timing constraints.

Key Specifications

Pinout & Package

24-ball FBGA (5 mm × 5 mm, 0.8 mm pitch) with 1.8 V/3.0 V dual-supply support (VCC/VCCQ). Ball assignment follows JEDEC MO-270DA standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PSRAM applications.

Compared with S27KS0643DPBHI020 (identical function) and W958D8MWYX1I (lower speed, no DCARS), the S27KL0643DPBHI020 offers optimal balance of industrial temperature rating, 200 MHz performance, and 12 µA deep power down - critical for thermally constrained edge AI deployments.

Availability

S27KL0643DPBHI020 is available at Aetrix Electronics and suitable for smart wearable display buffers, automotive ADAS preprocessing caches, and industrial PLC logic program storage requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for S27KL0643DPBHI020 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies AG is a German semiconductor manufacturer specializing in power management, sensing, and connectivity solutions for industrial, automotive, and IoT markets.

The HYPERRAM™ product line delivers high-speed, low-pin-count PSRAMs optimized for microcontroller-based systems needing external memory bandwidth without complex DRAM controller logic or refresh management overhead.

FAQ

Does S27KL0643DPBHI020 require external refresh circuitry?

No. The device contains integrated self-refresh logic that autonomously manages DRAM array refresh during idle periods. Host processors interact with it as a static RAM - no refresh commands, timers, or scheduling are needed in firmware. Refresh occurs transparently between transactions, triggered by internal counters aligned to temperature and voltage conditions.

What is the purpose of the RWDS signal in read versus write operations?

In read operations, RWDS outputs a strobe synchronized to read data edges to indicate valid data windows. In write operations, RWDS serves as a byte mask input - each rising edge enables writing to the corresponding DQ byte. This dual-role eliminates need for separate RD/WR control lines and reduces interface complexity compared to parallel SRAM.

Can S27KL0643DPBHI020 operate with only single-ended clock (CK), or is differential CK#/CK mandatory?

Single-ended CK is fully supported and sufficient for most applications. Differential CK#/CK is optional and improves noise immunity in electrically noisy environments (e.g., automotive under-hood). When enabled, CK# must be driven complementary to CK with matched trace length and termination - no additional configuration is required beyond hardware layout.

How does the hybrid burst mode differ from pure linear or wrapped burst in practice?

Hybrid burst executes one wrapped burst (e.g., 64-byte circular wrap) followed immediately by a linear burst (e.g., 32-byte sequential). This combines spatial locality benefits of wrapping (cache line reuse) with predictable addressing of linear access - ideal for streaming video decode where macroblock headers and pixel data have differing access patterns.