By Chris Morrison, VP Product Marketing at Agile Analog
In the current semiconductor landscape, security threats are scaling with the explosion of connected devices and Edge AI. Billions of SoCs that power everything from automotive ECUs to industrial IoT process sensitive data, often in untrusted environments.
As the complexity and range of security attack techniques have risen, tamper detection and prevention have become a hot topic. Hardware security—protecting the physical silicon inside devices—is increasingly being seen by electronic design engineers as a necessity rather than simply a “nice to have.”
Digital security alone is no longer sufficient. Analog anti-tamper IP and sensor solutions play an important role, providing an additional defensive layer needed to thwart unauthorized access or manipulation of devices. These sensors provide real-time environmental awareness across process, voltage, and temperature (PVT), with accuracies that exceed those of digital equivalents. Analog anti-tamper sensors include the following…
Clock attack monitors
One of the most common security attack methods—clock attacks—occurs when the clock signal that controls the timing of operations in a microprocessor is manipulated. A hacker will physically adjust the incoming clock’s frequency or timing to cause glitches or setup-and-hold violations. Clock attack monitors can be used to check the frequency and timing of the clock signal. Unforeseen changes in frequency or irregularities in the clock signals could indicate an imminent security attack. In that case, a clock attack monitor would quickly activate countermeasures, such as sending an alert, and then moving to safe mode or performing a hard reset.
Voltage glitch detectors
Voltage glitching is another well-known security attack method in which a hacker tampers with a device’s incoming power supply at a specific time to bypass the system’s security or disrupt normal operations. Voltage drops or spikes are induced to cause errors that can interrupt encryption algorithms, making a device vulnerable to side-channel attacks. Voltage glitch detectors can be implemented to continuously monitor the power supply; if an unexpected voltage change occurs, an alarm will be triggered and defensive actions will be taken.
Temperature sensors
Thermal attacks occur when a device is rapidly heated, cooled, or shifted from its usual operating state, causing faults that can alter the device’s system. Hackers can generate timing and supply errors without having physical access to the critical clock and supply lines. Temperature sensors can be used to detect sudden temperature variations. If there are high or low temperatures or unanticipated temperature changes, whether heating or cooling, this might be a sign of tampering. Then protection plans will be activated to safeguard data and prevent damage.
Electromagnetic sensors
Electromagnetic fault injection (EMFI) is an increasingly challenging physical hardware security attack vector that uses targeted electromagnetic pulse injection to induce temporary glitches or faults in a chip. Physical access to individual signals is not required for this form of tampering, which can penetrate through the device packaging. An EMFI sensor can be integrated onto the silicon chip. This allows even slight changes in the magnetic field to be detected, and an alert can be raised immediately to stop the attack. This means that EMFI sensors are especially suited to real-time monitoring and high-speed systems where data integrity is critical.
Laser fault injection sensors
Laser fault injection (LFI) attacks involve a hacker using a laser beam to cause errors in a chip’s operation, penetrating the front or back side of a device. An LFI sensor can be placed on a chip to monitor for sudden changes in photocurrent or light-induced timing disruptions. Rather than just looking for general light, these sensors are tuned to detect the specific transient characteristics of a malicious laser pulse. These sensors operate at hardware speed, and they do not rely on firmware or OS-level monitoring. Therefore, there is nanosecond-level detection and protection even during boot. This means LFI sensors can be used to protect root-of-trust components and secure cryptographic identity.
New analog anti-tamper solutions
Following the recent rise in the complexity of security attacks, new analog anti-tamper solutions have been launched onto the market. Agile Analog has introduced the agileSecure portfolio of customizable and process-agnostic analog anti-tamper IP. This IP can be integrated to protect SoCs and to deliver robust hardware-level security for devices operating in sensitive applications on advanced process nodes.
The tamper-detection IP features a range of anti-tamper sensors, including a clock-attack monitor, voltage-glitch detector, temperature sensor, and electromagnetic sensor. These analog-based solutions provide enhanced protection compared to conventional digital approaches used in secure enclaves and Root of Trust (RoT) systems.
The IP also incorporates an internally biased LDO, bandgap reference, oscillator, Power-on-Reset (PoR), and Power-OK monitors to further protect critical circuitry against external attacks.
It’s clear that analog anti-tamper sensor solutions have an important role to play in improving tamper detection and prevention, alongside digital and Root of Trust solutions, to deliver the superior levels of security required to protect the next generation of connected devices.
www.agileanalog.com