SWRU626 December 2025 CC3501E , CC3551E
The CC35xx device supports on-chip and off-chip memories. Memories are used for execution, data and non-volatile memory. The on-chip memory includes SRAM, and the off-chip memories supported are serial Flash (external or stacked) and serial PSRAM (stacked only).
SRAM is used for execution and data. It is divided into instruction and data partitions, as well as secure and non-secure. The instruction memory partition is split into Instruction Tightly Coupled Memory (ITCM) and Instruction Cache memory (I-Cache). I-Cache allows for execution from Flash and the PSRAM (Refer to current sofwate development kit (SDK) for support). Data memory is divided into Data Tightly Coupled Memory (DTCM) and non-TCM (DMEM), as well as Data Cache Memory (D-Cache). The D-Cache is designed to access the PSRAM.
Flash is non-volatile memory used for execution and for data storage. The PSRAM is used predominantly as data storage.
Each of the memories can be accessed by the M33 MCU, µDMA and the Host DMA. The µDMA is used for data transfer between the external Flash/PSRAM and on-chip SRAM. The host DMA is used for data transfer between peripherals and the device's on-chip SRAM.
The following diagram describes the device memories and which can access it:
The properties of the available memories are listed in the table below:
| Memory | Description | Size(1) | CLK | Secure/Non-Secure partition |
|---|---|---|---|---|
| Internal Memories | ||||
| I-Cache | Instruction Cache Memory |
32kB / 64kB configurable |
160MHz |
Not required. Supported by M33 trust-zone (accessed by M33 only) |
| ITCM | Instruction Tightly Coupled Memory |
32kB / 0 configurable |
160MHz | Supported |
| D-Cache | Data Cache Memory |
0 / 32kB / 64kB configurable |
160MHz |
Not required. Supported by M33 trust-zone (accessed by M33 only) |
| DTCM | Data Tightly Coupled Memory |
128kB / 96kB / 64kB configurable |
160MHz | Supported |
| DMEM | Data Memory |
256kB configurable |
80MHz | Supported |
| External Memories | ||||
| Flash | External Flash | Up to 64MB (8MB executable) |
xSPI I/F | Supported |
| PSRAM | Stacked PSRAM | Up to 64MB | xSPI I/F | Supported |