CSS6404L
Manufacturer: Cascadeteq
The CSS6404L is a 64 Mbit QSPI pseudo-static RAM. PSRAM contains a DRAM array behind an on-chip refresh controller, so externally it behaves like SRAM — no refresh logic in the host — while offering DRAM-level density. That is what makes it a practical replacement for an asynchronous SRAM or a parallel DRAM in a design where pin count and board area are constrained.
Overview
The CSS6404L is a 64 Mbit Quad-SPI pseudo-SRAM (PSRAM) from Cascadeteq, organised as 8 M x 8 bits. It runs from a single 2.7 – 3.6 V supply and communicates over a four-bit SPI or QPI interface at clock rates up to 133 MHz for 32-byte wrapped burst operation at 3.0 V, 109 MHz at 3.3 V and 84 MHz for linear burst, with 1024-byte pages. Maximum standby current is 350 µA at 105 °C, falling to 100 µA at 25 °C.
The interface uses few pins while providing DRAM-like density, which is the point of PSRAM: it adds working memory to a microcontroller without the pin count of a parallel bus. It is intended for embedded systems that need more RAM than the MCU provides — graphics buffers, network stacks and data queues.
Key features
- SRAM-like interface with DRAM-level density
- On-chip refresh removes host refresh logic
- QSPI interface keeps pin count low
Typical applications
- Working memory in compact embedded designs
- Replacing asynchronous SRAM or parallel DRAM
- Buffer memory in consumer and industrial devices
Specifications
Memory
| Density | 64 Mbit (8 Mbyte) |
|---|---|
| Type | Pseudo-static RAM (PSRAM) |
| Interface | QSPI |
| Refresh | Self-managed on-chip, host sees SRAM behaviour |
Electrical
| Supply voltage | 3.3 V |
|---|
Note on parameters. The figures above are taken from the manufacturer datasheet for CSS6404L. Electrical limits vary by ordering option and revision — confirm the current datasheet before finalising your design.
Package and ordering
| Ordering code | Package | Operating temp. / grade |
|---|---|---|
| CSS6404L | SOP-8 / DFN | Tape & reel |
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Sourcing CSS6404L
We supply CSS6404L with original manufacturer documentation and a quotation that states lead time, packaging and price breaks. Send your annual quantity and target date and you will get a reply with the datasheet attached.