Clock and Frequency Configuration
What is the clock architecture of the RK182X?
The RK182X is an AI coprocessor (Device) connected to the Host SoC over PCIe/USB/EtherNet; it does not carry the full SoC clock-tree responsibilities of CPU/GPU/display. Its core clock management revolves around NPU frequency levels and the thermal throttling strategy. (Source: RK1820_RK182X AI SDK Quick Start, §1.1)
Host SoC (RK3588 etc.)
│ PCIe / USB / EtherNet
▼
RK182X coprocessor
├── NPU cores (500 / 850 / 1000 MHz)
├── NPU core memory (5120 MB / 2560 MB)
└── Thermal fan + throttling managementWhat NPU frequency levels are available?
The RK182X supports three NPU frequency levels, determined by the performance mode (source: RK1820_RK182X AI SDK Quick Start, §7.3):
| Performance level | NPU frequency (SODIMM) | NPU frequency (M.2) | Description |
|---|---|---|---|
| PERFORMANCE | 1000 MHz | 850 MHz | Maximum performance, default |
| NORMAL | 850 MHz | 850 MHz | Standard mode |
| EFFICIENT | 500 MHz | 500 MHz | Power-saving mode, lower consumption |
Due to cooling limits, M.2 modules are capped at 850 MHz (source: RK1820_RK182X AI SDK Quick Start, §7.3).
How does thermal control throttle the frequency?
When the temperature exceeds a threshold the system throttles automatically; above 100℃ a forced reboot is triggered (source: RK1820_RK182X AI SDK Quick Start, §7.3):
| Temperature threshold Tmargin (℃) | Fan speed (%) | Max NPU frequency (MHz) |
|---|---|---|
| 0 | 0 | 1000 |
| 46 | 51 | 1000 |
| 60 | 63 | 1000 |
| 68 | 78 | 1000 |
| 76 | 100 | 1000 |
| 83 | 100 | 850 |
| 90 | 100 | 500 |
| 100 | — | Forced reboot |
NPU power supply and consumption?
Power and supply data for the RK182X (source: RK1820_RK182X AI SDK Quick Start, §4.3.1.2):
| Parameter | RK1820 | RK182X |
|---|---|---|
| NPU core DRAM | 2.5 GB | 5 GB |
| Typical power | 1631 mW | — |
| Device power | 1681 mW | — |
| Standby power | — | 81 mW |
| Typical temperature | 26℃ | 44℃ |
How do I view/set the NPU frequency?
View and set the frequency via the RKNN-SMI tool or system interfaces (source: RKNN-SMI Tool User Guide V1.3.1):
# 查看 NPU 状态（频率、温度、功耗、利用率）
rknn-smi info
# 查看模组功耗
rknn-smi info -t power
# 设置性能模式
rknn-smi set-mode --mode performance # 1000 MHz (SODIMM)
rknn-smi set-mode --mode normal # 850 MHz
rknn-smi set-mode --mode efficient # 500 MHzFirmware frequency support
Firmware Release V1.0.4 adds support for a 950 MHz frequency point (srv/vrv) (source: RK1820_RK182X AI Release-Note_CN.md, §5).
Related documents
- Power Management — power consumption and supply
- NPU Subsystem — NPU hardware and inference
- SDK Overview — overall architecture