The timing accuracy of mining detonators has a significant influence on the safety and effectiveness of blasting operations. The detonation train needs precise timing. A lack of precise control can result in undesirable outcomes.
Detonators must be resilient and reliable. They must be designed to avoid misfires under the harshest of conditions such as shock from nearby explosions, ground vibration, gas or water intrusion, temperature extremes, and EMI. SiTime MEMS timing solutions are designed to operate under such extreme conditions and provide the required robustness and reliability for safe operation.
Complete MEMS clock treeSmall-footprint oscillators (XO) Low jitter differential XO Low power 32.768 XO |
Accurate and robustResilience to shock, vibration, EMI Hermeticity of the MEMS resonators Excellent stability over temperature |
Easy to use, built to lastProgrammable features No quartz reliability issues >2 billion hour MTBF |
Detonators (also called blasting caps) are used to trigger an explosive device in applications such as mining, quarrying and civil engineering. Commercial explosives are made stable and safe to handle, so they will not explode if accidentally dropped, mishandled or exposed to fire. For this reason, they require a small initiating explosion to be set off. This is provided by a detonator.
The timing accuracy of detonators used in the mining industry has a significant influence on the safety and effectiveness of blasting operations. A "detonation train" with precise timing is used to blast rock; lack of precise control can result in undesirable outcomes such as flyrock (rocks projected by the blast in an undesired direction), excessive ground vibration, uneven grade of rock as well as misfires or unintended firing.
Individual wired detonators are usually connected in parallel, via a differential line, to a programming and firing unit. The line provides both power as well as individual commands – such as delay programming, arming, disarming and firing – to the detonators. The firing order is programmed into the detonators by adjusting a time delay from the start of the sequence, to the moment the individual detonator fuses. All detonators are triggered simultaneously; the individual delay of each detonator executes the blast pattern.
Resilience and reliability are key parameters for detonators. They must be designed to avoid misfires and unintended firing under the harshest of conditions: shock from nearby explosions, ground vibration, gas or water intrusion, temperature extremes, etc. EMI interference is a common reason for unintended firing, which can be caused by lightning, static electricity, nearby radiofrequency transmitters, or stray currents from defective equipment.
Once the firing sequence is initiated and explosions start, detonators are likely to be disconnected from the power + communication line. For this reason, they feature an internal power supply capacitor which keeps them running until the fuse is triggered. The timing until the fuse is fired is managed by a microcontroller, using a reliable timing source such as the SiT1811 oscillator.
Wireless detonators follow a similar operating principle as wired detonators. They are battery-powered and replace the power + communication line by radio transmission. Several techniques exist to create wireless transmitters and receivers; some of them rely on a clock source. A high-stability, low-jitter clock source enables more reliable transmission, lower error rate, and less interference.
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MHz oscillator
SiT8021 1 to 26 MHz
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32.768 kHz oscillator
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Differential oscillator
SiT9366 1 to 220 MHz
SiT9367 220 to 725 MHz
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1 12 kHz to 20 MHz integration range
Higher Reliability |
Better Quality, More Robust |
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Millions of Configurations |
Immune to Vibration |
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