Tesla’s shift from FPGA/GPU-based systems to custom ASICs (e.g., FSD Chip, Dojo D1) represents a strategic divergence from industry norms. Here’s how FPGA solutions compare to Tesla’s approach in LiDAR/vision processing:
1. Architectural Comparison
2. Sensor Processing Capabilities
FPGAs (e.g., Xilinx for LiDAR)
Strengths:
- Handle multi-sensor fusion (LiDAR + radar + cameras) with parallel pipelines.
- Support legacy protocols (CAN FD, Automotive Ethernet).
Weaknesses:
- Higher power than ASICs for equivalent TOPS.
- Limited AI acceleration (vs. dedicated NPUs).
Tesla’s ASICs (Vision-Only)
Strengths:
- Custom SRAM-on-chip (32MB cache for FSD Chip) reduces DRAM latency.
- Dojo’s 1.1 EFLOPS supercomputer trains vision models at scale.
Weaknesses:
- No native LiDAR/radar support (relies purely on cameras).
- Inflexible to new sensor modalities (e.g., 4D radar).
3. Real-World Implementations
FPGA Examples:
- Luminar Iris (Xilinx FPGA): Processes 200m+ LiDAR data for Volvo.
- Continental ARS540 (Xilinx RFSoC): 4D imaging radar with MIMO processing.
Tesla’s ASIC Examples:
FSD Chip (HW3/HW4):
- 144 TOPS (HW3) → 256 TOPS (HW4) for 8-camera vision pipelines.
- Uses dual NPUs for transformer-based “HydraNet” models.
Dojo D1 Tile:
- 362 TFLOPS (FP32) for autonomous training.
- 1.25TB/s bandwidth via custom interconnect.
4. Cost & Scalability
5. Future-Proofing
- FPGAs: Better for evolving standards (e.g., transitioning to 4D LiDAR or neuromorphic radars).
- ASICs: Tesla’s vertical integration allows tight hardware-software co-design (e.g., optimizing for “BEV transformers”).
Key Takeaways
- For Sensor-Agnostic Systems: FPGAs win (used by 90% of LiDAR/radar vendors).
- For Vision-Only Scale: Tesla’s ASICs are unbeatable in performance/power.
- Hybrid Future: Startups like SiFive are blending FPGA-like programmability with ASIC efficiency.
Tesla’s Lesson: ASICs only make sense if:
- You control the entire stack (sensors → algorithms).
- Your volume justifies NRE costs.
- You’re willing to freeze architectures for 5+ years.
FPGA vs. ASIC Decision Flowchart
plaintext
┌───────────────────────┐
│ Need sensor flexibility? │
└──────────┬─────────────┘
│
┌───────────────▼────────────────┐
│ │
┌────────▼───────┐ ┌─────────▼─────────┐
│ Choose FPGA │ │ Choose ASIC │
│ (Luminar, BMW)│ │ (Tesla, Apple) │
└────────────────┘ └───────────────────┘