Ca HK Galil Controller
- Steve Gibson
Table of Contents:
Overview
This device is a Galil RIO which is employed to:
control a TTL-level signal for the HK detector
control a TTL-level signal for the HK shutter controller
measure temperatures within the HK spectrometer system
It was initially chosen because it is not possible for the HK Detector (Andor Newton) SDK commands to start and end an exposure of unknown length (this type of exposure is needed for when the exposure meter is controlling the KPF exposure length). However, exposures of unknown length are possible via the ‘External Exposure (Bulb)' mode; in this mode the exposure start and end are controlled by the Newton monitoring a TTL signal on its External Trigger Input. The Galil RIO is utilized to generate this signal.
Since the shutter is controlled by a similar signal, it was decided to use this Galil to control the shutter as well. This offers a lot of flexibility, provides robust timing, and places the software complexity on the Galil (a well understood system). This was considered to be preferable to controlling the shutter through the Newton, which would have increased the complexity of the Newton dispatcher and likely introduced some Andor SDK software latencies.
The thermal sensors were added to the Galil as this approach avoids using another device (a LinkHub-E, for example), and also because Galil offers an OTS breakout board for reading RTD sensors.
Relevant Devices
Description | Qty | Source | Part Number | Notes |
|---|---|---|---|---|
Ca HK Computer Interface | 1 | Galil | RIO-47142-16BIT |
|
Galil Controller Power Supply | 1 | Galil | PSR-12-24 |
|
Galil Output Bank Power Supply | 1 | Tri-Mag, LLC | Tri-Mag PN: L6R12H-120 | DigiKey PN: 364-1264-ND |
Shutter Controller | 1 | Uniblitz | VED24 | See https://keckobservatory.atlassian.net/wiki/spaces/KPFElectronics/pages/1552580609 |
Temperature Sensor Interface Board | 1 | Galil | SCB-48206 |
|
Temperature Sensors (Surfaces) | 4 | Omega | RTD-831-MTP |
|
Temperature Sensors (Air) | 2 | Omega | RTD-860-MTP |
|
Ca HK Detector | 1 | Andor | Newton 920P-BU | See Ca HK Detector |
Relevant Functional Block Diagrams
Complete Ca H&K Spectrometer electronics schematic:
Internal details and external connections for the HK Galil Enclosure:
More details on the TTL signals generated by the Galil are included here: https://keckobservatory.atlassian.net/wiki/spaces/KPFElectronics/pages/1511915863
Relevant Datasheets & Manuals
Description | File | Source | |
|---|---|---|---|
| 1 | Galil Manual NOTE: Appendix 1 is dedicated to reading temperatures from the RTD board we're using |  | Galil website |
| 2 | Output Bank Power Supply Datasheet |  | https://www.tri-mag.com/wp-content/uploads/2021/05/L6R12H_Series_2021-01.pdf (Linked off the DigiKey product page) |
| 3 | Ca HK Detector |
| See Ca HK Detector |
| 4 | Shutter and Controller Details |
| See https://keckobservatory.atlassian.net/wiki/spaces/KPFElectronics/pages/1552580609 |