d2:laser_servo
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d2:laser_servo [2018/11/14 17:38] – [Right Side Panel] Michael Radunsky | d2:laser_servo [2019/02/21 15:55] – [Right Side Panel] Michael Radunsky | ||
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Please read [[: | Please read [[: | ||
+ | |||
+ | [[https:// | ||
+ | [[https:// | ||
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=====Specifications===== | =====Specifications===== | ||
<WRAP center round box 600px> | <WRAP center round box 600px> | ||
- | | | **Value** | + | | | **Value** |
- | |**Input and Output Impedance**| | + | | **Input and Output Impedance** |
- | |**Output Voltage (main and aux)**| | + | | **Output Voltage (main and aux)** |
- | |**Input Voltage Noise**(( Referenced to 50Ω load))| | + | | **Input Voltage Noise**(( Referenced to 50Ω load)) |
- | |**Max Input Voltage DC Level**| | + | | **Max Input Voltage DC Level** |
- | |**Max Input Voltage Signal Amplitude**| | + | | **Max Input Voltage Signal Amplitude** |
- | |**Bandwidth**(( Oscillation frequency when Laser Servo locked to itself in proportional mode.))| | + | | **Bandwidth**(( Oscillation frequency when Laser Servo locked to itself in proportional mode.)) |
- | |**Proportional Gain (ref to DC Error)**\\ **Proportional Gain (ref to Input Error)**| | + | | **Proportional Gain (ref to DC Error)**\\ **Proportional Gain (ref to Input Error)** |
- | |**First Integrator**| | + | | **First Integrator** |
- | |**Second Integrator**| | + | | **Second Integrator** |
- | |**Differential**| | + | | **Differential** |
- | |**Differential Gain**| | + | | **Differential Gain** |
- | |**Auxiliary Servo Output | + | | **Auxiliary Servo Output |
- | |**Laser Freq. Jump**| | + | | **Laser Freq. Jump** |
- | |** Jump Time**| | + | | ** Jump Time** |
- | |**Ramp Amplitude (Max)**| | + | | **Ramp Amplitude (Max)** |
- | |**Ramp Frequency (on main servo output) \\ Ramp Frequency (on aux servo output)**| | + | | **Ramp Frequency (on main servo output) \\ Ramp Frequency (on aux servo output)** |
- | |**Dither Frequency (-PL only)**| | + | | **Dither Frequency (-PL only)** |
- | |**RF Output Max Amplitude (-PL only)**| | + | | **RF Output Max Amplitude (-PL only)** |
- | |**RF Output Impedance (-PL only)((Into a 1 MΩ load)) **| 50 | Ω | | + | | **RF Output Impedance (-PL only)((Into a 1 MΩ load)) ** | 50 | Ω | |
- | |**Ramp Centering Range **| ±5 | V | | + | | **Ramp Centering Range ** | ±5 | V | |
</ | </ | ||
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**Coarse Gain (seven-position switch)** | **Coarse Gain (seven-position switch)** | ||
- | The COARSE GAIN sets the overall proportional gain of the circuit without changing the location of any zeros or poles in the loop filter transfer function. | + | The COARSE GAIN sets the overall proportional gain of the circuit without changing the location of any corners |
The overall loop gain (controlled by both the COARSE GAIN and the FINE GAIN) should be set around the point that minimizes the RMS noise on the DC ERROR MONITOR. This can sometimes result in setting the gain too high because the DC ERROR MONITOR filters high frequencies and thus hides some of the gain peaking with high gain. To precisely set the gain, look at the noise with a spectrum analyzer through the AC ERROR MONITOR. | The overall loop gain (controlled by both the COARSE GAIN and the FINE GAIN) should be set around the point that minimizes the RMS noise on the DC ERROR MONITOR. This can sometimes result in setting the gain too high because the DC ERROR MONITOR filters high frequencies and thus hides some of the gain peaking with high gain. To precisely set the gain, look at the noise with a spectrum analyzer through the AC ERROR MONITOR. | ||
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** Ramp-> | ** Ramp-> | ||
- | This 2-position slider switch is only accessible by removing the right side panel (see above) and sets whether the ramp is applied to the SERVO OUTPUT or the AUXILIARY SERVO OUTPUT. It is factory set in the Ramp-> | + | This 2-position slider switch is only accessible by removing the right side panel (see above) and sets whether the ramp is applied to the SERVO OUTPUT or the AUXILIARY SERVO OUTPUT. It is factory set in the Ramp-> |
===Aux Gain: + / Aux Gain - (2-position switch)=== | ===Aux Gain: + / Aux Gain - (2-position switch)=== | ||
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**Relative Jump TTL (BNC)** | **Relative Jump TTL (BNC)** | ||
- | When asserted HIGH (5V) while in LOCK mode, RELATIVE JUMP engages a sample-and-hold circuit and takes the Laser Servo out of lock. The voltage on the SERVO OUTPUT is the sample-and-hold value summed in with the LASER JUMP AMPLITUDE. For example, if the laser is locked and the SERVO OUTPUT is -200 mV, then engaging the RELATIVE JUMP and putting 300 mV on the LASER JUMP AMPLITUDE will make the SERVO OUTPUT | + | When asserted HIGH (5 V) while in LOCK mode, RELATIVE JUMP engages a sample-and-hold circuit and takes the Laser Servo out of lock. The voltage on the SERVO OUTPUT is the sample-and-hold value summed in with the LASER JUMP AMPLITUDE. For example, if the laser is locked and the SERVO OUTPUT is -200 mV, then engaging the RELATIVE JUMP and putting 300 mV on the LASER JUMP AMPLITUDE will make the SERVO OUTPUT |
When asserted HIGH (5V) while in RAMP mode, RELATIVE JUMP applies a DC offset equal to the LASER JUMP AMPLITUDE to the ramp signal at SERVO OUTPUT. When asserted LOW (0V) while in RAMP mode, the ramp signal is DC balanced. | When asserted HIGH (5V) while in RAMP mode, RELATIVE JUMP applies a DC offset equal to the LASER JUMP AMPLITUDE to the ramp signal at SERVO OUTPUT. When asserted LOW (0V) while in RAMP mode, the ramp signal is DC balanced. |
d2/laser_servo.txt · Last modified: 2021/12/17 01:58 by 127.0.0.1