Which flight controller processor should I choose: F4, F7, H7, or AT32?

For 2025 builds, the STM32F722 (F7) is the recommended choice for 90% of pilots. It runs all Betaflight features (RPM filtering, GPS Rescue, D-Min tuning, 8kHz blackbox) with 50% CPU headroom. The H7 is premium overkill for advanced builds. The AT32 is a budget F7 alternative. F4 is legacy — Betaflight 4.6+ will not support it. Price range: F4 $25-40, AT32 $30-50, F7 $35-55, H7 $45-70.

Is the F4 flight controller still worth buying in 2025?

No, the F4 (STM32F405) is not recommended for new builds in 2025. Betaflight has announced that F4 support will be dropped after version 4.5.x — meaning future firmware updates (4.6+) will not work on F4 boards. F4 also struggles to run RPM filtering and GPS Rescue simultaneously, with CPU loads hitting 85-95%. Only buy F4 for spare parts or budget backup quads where you don't need future firmware updates.

How many UARTs do I need on a flight controller?

A modern FPV build needs at minimum 4 UARTs: one for the receiver (CRSF/SBUS), one for GPS, one for VTX SmartAudio control, and one spare. If you want camera control, ESC telemetry, or a secondary receiver, you need 5-6 UARTs. F7 and H7 boards typically provide 6-8 UARTs. F4 boards have 5-6 but may sacrifice features to GPIO conflicts. Always check the specific FC wiring diagram — not just the UART count — to verify that your planned peripherals don't conflict.

What is the difference between MPU6000 and ICM-20689 gyros?

The MPU6000 (SPI) is the gold standard FPV gyro — it's more resistant to electrical and mechanical noise than the newer ICM-20689. The ICM-20689 is more sensitive on paper but picks up more frame resonance and motor noise, requiring more aggressive filtering that can reduce flight performance. When choosing between two otherwise identical flight controllers, always prefer the one with an MPU6000 gyro. Many premium F7 and H7 boards use dual-gyro setups with one of each for redundancy.

FPV Flight Controller Comparison: F4 vs F7 vs H7 vs AT32 Processor Guide

# FPV Flight Controller Comparison: F4 vs F7 vs H7 vs AT32 Processor Guide

Choosing the right flight controller is one of the most consequential decisions in any FPV build. The processor on your FC determines which features you can run simultaneously, how many UARTs are available, and whether you can use cutting-edge firmware features. This guide compares all four major FC processor families — F4, F7, H7, and AT32 — and helps you pick the right one for your build.

## Processor Comparison at a Glance

| Specification | F4 (STM32F405) | F7 (STM32F722) | H7 (STM32H743) | AT32 (AT32F435) |
|————–|—————-|—————–|—————–|—————–|
| CPU Core | Cortex-M4 | Cortex-M7 | Cortex-M7 | Cortex-M4 |
| Max Clock Speed | 168 MHz | 216 MHz | 480 MHz | 288 MHz |
| Flash Memory | 1MB | 512KB | 2MB | 4032KB |
| RAM | 192KB | 256KB | 1MB | 512KB |
| Hardware FPU | Single precision | Single precision | Double precision | Single precision |
| Typical UART Count | 5-6 | 6-8 | 8-9 | 5-8 |
| Price Range | $25-40 | $35-55 | $45-70 | $30-50 |
| Firmware Support | Betaflight 4.5 ✓ | Betaflight 4.5 ✓ | Betaflight 4.5 ✓ | Betaflight 4.5 ✓ |
| RPM Filtering | Yes* | Yes | Yes | Yes |
| GPS Rescue | Yes* | Yes | Yes | Yes |
| Future-Proof Through | 2025 limited | 2026 | 2027+ | 2026+ |
| Current Status | **Legacy — being phased out** | **Current standard** | **Premium/Pro** | **Value alternative** |

*F4 can run RPM filtering and GPS Rescue, but CPU load may approach 80-90%, limiting additional features.

## Deep Dive: Each Processor

### STM32F405 (F4) — The Legacy Workhorse

The F4 powered the FPV revolution from 2016-2022. Betaflight’s decision to deprecate F4 support means new firmware versions after 4.5.x will not support F4 targets.

**What F4 can still do well:**
– 8kHz PID loop with basic features
– RPM filtering (bidirectional DShot)
– GPS Rescue (basic, no advanced sanity checks)
– OSD with essential elements

**What F4 struggles with:**
– Simultaneous RPM filtering + GPS Rescue + full OSD → 85-95% CPU load
– High-speed logging (blackbox at 2kHz max, not full rate)
– Advanced features like FFT-based dynamic filtering
– Future Betaflight versions (4.6+ will drop F4)

**Verdict**: Only buy F4 for budget builds or spare/backup quads. Do not use in new 2025+ builds.

### STM32F722 (F7) — The Current Gold Standard

The F722 variant of the F7 family is the sweet spot for 95% of FPV pilots. It offers enough CPU headroom to run every major Betaflight feature simultaneously without breaking a sweat.

**What F7 does best:**
– 8kHz PID loop with 40-55% CPU headroom
– RPM filtering + GPS Rescue + full OSD + D-Min simultaneously
– 8kHz blackbox logging
– Full FFT and dynamic filtering support
– 6+ hardware UARTs for peripheral connectivity

**Verdict**: The default choice for any 5-inch or larger build in 2025. Buy an F7 unless you have a specific reason not to.

### STM32H743 (H7) — The Premium Powerhouse

The H7 is overkill for most pilots, but the massive CPU headroom means you never have to think about feature limits. The dual-core architecture and 480MHz clock speed are future-proof through at least 2027.

**When H7 makes sense:**
– Heavy GPS Rescue users who want instant response
– Pilots running 32kHz gyro sampling
– Builds with extensive peripheral requirements (radar, lidar, companion computers)
– Future-proofing against Betaflight feature bloat
– The cost difference ($15-25) over F7 is worth the peace of mind

**What H7 enables that F7 cannot do:**
– 32kHz gyro loop without CPU stress
– Simultaneous high-rate blackbox and full OSD
– Custom firmware features and scripting
– Stable operation with 9+ UARTs and SPI devices
– Double-precision floating point (more accurate PID math)

**Verdict**: Buy H7 if you want the absolute best, plan to keep the FC for 3+ years, or push the limits of what Betaflight can do.

### AT32F435 (AT32) — The Rising Challenger

Artery’s AT32 series emerged as a STM32 alternative during the chip shortage, and it has proven itself as a capable and cost-effective F7 competitor. The AT32F435 offers F7-class performance at F4 prices.

**AT32 considerations:**
– Smaller community and fewer troubleshooting resources
– Not all Betaflight targets have AT32 variants
– Slightly less mature firmware optimization
– Some advanced features may lag behind STM32 releases by 1-2 versions

**Verdict**: A viable budget alternative to F7. Best for pilots comfortable with slightly less polished firmware support.

## Feature Support Matrix

| Feature | F4 | F7 (F722) | H7 | AT32 |
|———|—-|———–|—-|—-|
| 8kHz PID Loop | ✓ (high CPU) | ✓ (50% CPU) | ✓ (25% CPU) | ✓ (45% CPU) |
| RPM Filtering | ✓ (limited) | ✓ | ✓ | ✓ |
| D-Min Tuning | ✓ | ✓ | ✓ | ✓ |
| GPS Rescue (basic) | ✓ | ✓ | ✓ | ✓ |
| GPS Rescue (advanced) | ✗ | ✓ | ✓ | ✓ |
| 8kHz Blackbox Log | ✗ (2kHz max) | ✓ | ✓ | ✓ |
| Dynamic Notch (multiple) | ✓ (2 notches) | ✓ (4+ notches) | ✓ (4+ notches) | ✓ (3+ notches) |
| Dual Gyro | ✗ | ✓ (some FCs) | ✓ | ✗ |
| Camera Control (UART) | ✗ | ✓ | ✓ | ✓ |
| Betaflight 4.6+ Support | ✗ (dropped) | ✓ | ✓ | ✓ |
| iNav Support | ✓ | ✓ | ✓ | ✓ |
| ArduPilot Support | ✗ | ✗ | ✓ (limited) | ✗ |

## Decision Flowchart

“`
What’s your budget?
├─ Under $30 → AT32 or used F7
├─ $30-45 → F7 (STM32F722)
└─ $50+ → H7 (STM32H743)

What are you building?
├─ 3-inch micro / toothpick → F4 is fine, AT32 for future-proofing
├─ 5-inch freestyle → F7 standard, H7 for premium
├─ 5-inch racing → F7 (lightweight priority)
├─ 7-inch long range → F7 minimum, H7 strongly recommended
├─ Cinewhoop → F7 (GPS Rescue is important)
└─ X-Class / heavy lifter → H7 only

How long will you keep this FC?
├─ <1 year or backup quad → F4 or AT32 ├─ 1-2 years → F7 └─ 3+ years → H7 ``` ## Final Recommendation For 90% of pilots building in 2025, **buy an F7 (STM32F722)**. It runs every meaningful Betaflight feature with room to spare, costs $35-55, and will be supported through at least Betaflight 4.6. If you find an F7 with an MPU6000 gyro (rather than ICM-20689), buy it — the MPU6000 is more noise-resistant. For the 10% who want the absolute best or plan extreme builds, the **H7** is worth the premium. For budget-conscious builders, the **AT32** is a capable alternative. Avoid F4 for anything except spare parts. The [UAV Model F7 V2 Flight Controller](https://uavmodel.com) combines an STM32F722 processor with a low-noise MPU6000 gyro, 6 full UARTs, onboard blackbox flash, and a plug-and-play connector system — everything a modern 5-inch build needs without compromises.

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