Synaptics Fs7605 Touch Fingerprint Sensor With Pureprint-tm- Top
Host (AP) <--SPI--> FS7605
<--IRQ-->
<--I2C--> (touch config)
Driver stack:
How does it stack up against the Qualcomm 3D Sonic (ultrasonic) or the Goodix optical sensors used in smartphones?
| Feature | Synaptics FS7605 | Ultrasonic (Qualcomm) | Optical (Under-Display) | | :--- | :--- | :--- | :--- | | Spoof Detection | PurePrint (AI/Analog) | Ultrasonic Impedance | RGB Light (Easier to fool) | | Wet Finger Rejection | Excellent (High) | Excellent | Poor (Light scatters) | | Power Consumption | Ultra-Low (15µW sleep) | High | Medium | | Surface Material | Glass/Metal/Plastic | Required flexible OLED | Only Transparent Glass | | Liveness Standard | TOP (Hardware) | Software Layer | Software Layer | Driver stack: How does it stack up against
Conclusion: The FS7605 is the "tank" of the industry. It trades off aesthetic "under-display" placement (though it can go under a bezel) for raw, uncompromised security and reliability.
The FS7605 is an optical sensor. Unlike ultrasonic sensors (like Qualcomm’s 3D Sonic), which use sound waves to map a fingerprint, optical sensors essentially take a photograph of your finger. The FS7605 is an optical sensor
Historically, optical sensors struggled with two things: speed (they were slower than capacitive sensors) and security (a high-res photo could sometimes fool them). This is where PurePrint™ enters the chat.
PurePrint™ is a combination of hardware and AI algorithms designed to distinguish between live skin and spoof materials (like latex, rubber, or printed paper). It uses dynamic pixel optimization to read the unique characteristics of the skin's ridge flow, even if the finger isn't perfectly placed. Windows Hello for Business
With Windows Hello requiring SecureBio (a standard that mandates anti-spoofing), the FS7605 is the gold standard. It allows for password-less login, Windows Hello for Business, and integration with Azure Active Directory.
| Feature | Benefit | |---------|---------| | Gesture detection | Swipe down (notifications), double‑tap (wake), long‑press (action) directly from sensor area without separate touch IC. | | Reduced Z‑height | Total module height ≤ 1.2 mm (40% thinner than sensor + separate touch button). | | Water rejection | TMR layer provides baseline touch detection even when sensor surface is wet; fingerprint capture degraded but wake/gesture still works. | | Wake‑on‑touch | Sensor enters µA mode and uses TMR layer to detect approach/wake, avoiding need for proximity sensor. |
| Aspect | Host CPU Liveness (e.g., software) | PurePrint™ on FS7605 | |--------|--------------------------------------|------------------------| | Data exposure | Raw fingerprint image to OS | Only binary accept/reject | | Anti-hacking | Vulnerable to OS-level interception | Secure enclave – no bus access to raw frames | | Speed | 100–300 ms (depends on CPU load) | 25 ms fixed | | Power | High (wakes application processor) | Low (dedicated NPU core) |