AccuBeat NAC1, User Manual

Page 1: ...Document No ZD24010 Rev B2 Nano Atomic Clock NAC1 User Manual AccuBeat Ltd 5 Ha Marpeh Str Har Hotzvim P O Box 45102 Jerusalem 91450 Israel...

Page 2: ...escription Date ECO No Approved A Initial Revision 10 09 15 A S A6 Specification updated 11 09 16 A S B1 Specification updated 19 12 16 A S B2 Specification updated 29 04 18 C L Tel 972 2 5868330 Fax...

Page 3: ...tes 1 To avoid electric shock or fire hazard Apply voltage to the connectors as specified in the product Electrical ICD specifications Do not connect the unit to power supply with reverse polarity Ope...

Page 4: ...are 12 3 3 Cabling 14 3 4 Evaluation Board Overview 14 3 5 Initial Start Up 16 3 5 1 Initial Power On 16 3 5 2 Establishing Communication with NAC1 16 3 5 3 Basic NAC1 GUI Features 17 3 5 4 Frequency...

Page 5: ...16 Figure 8 NAC1 Block Diagram 20 Figure 9 BIT LED indication 21 Figure 10 NAC1 10MHz Output Driver 21 Figure 11 Evaluation Board 10MHz Output Driver 22 Figure 12 Mechanical ICD 26 List of Tables Tab...

Page 6: ...outputs at 10MHz and 1PPS The small size and low power consumption of the NAC1 enables atomic timing accuracy in various applications such as GPS receivers UAV s Autonomous sensors and Backpack secur...

Page 7: ...output 10MHz 1PPS Medium term stability 2E 11 100s Phase noise 148 dBc Hz 100 KHz relative to the main 10MHz output Size 32cc 41 1mm X 35 3mm X 22 mm Weight 75 grams Communication RS 232 CMOS 3 3V 1M...

Page 8: ...d to AccuBeat for service 2 3 Absolute Maximum Ratings Table 1 indicates the absolute maximum ratings to which the NAC1 can be subjected without permanent unrecoverable damage Note that the NAC1 canno...

Page 9: ...s not present in the NAC1 For initial testing and evaluation it is recommended that the pins should not be modified or soldered to a PCB The recommended socket for connecting the PCB is SAMTEC P N SC...

Page 10: ...dix C Software ICD CLI 6 Rx Comm Receive 6 7 Vcc Input Voltage 3 3 VDC 0 1 VDC 4 8 GND Ground 9 1PPS IN 1 Pulse Per Second Input 2 5 V Logic H Vcc 0 V Logic L 0 5 V 2 6 4 8 10 1PPS OUT 1 Pulse Per Sec...

Page 11: ...00 4 USB to Serial Cable AccuBeat P N ZE00314 5 Protective sheet AccuBeat P N MT30160 3 1 Installing the NAC1 on the evaluation board In an ESD safe environment carefully remove the NAC1 and the evalu...

Page 12: ...ne available RS232 COM or USB port Note that multiple NACs can be monitored from a single PC provided additional COM ports are available To install the NAC1 GUI software insert the provided CD ROM int...

Page 13: ...on Unzip The directories will be unzipped and the following installation messages will open Figure 4 LabVIEW85RuntimeEngineFull installation Figure 5 visa441runtime installation Finish both installati...

Page 14: ...ort RS232 Serial communication that was supplied with the NAC1 Evaluation Kit Connect banana to banana cables Red Black between J36 and J52 power input connectors and a 6V DC power supply VCC and Grou...

Page 15: ...DB9F DB9F RS232 cable To avoid problems please use the proper cable which is provided by AccuBeat with the Evaluation Kit BIT Lock Indicator LED Indicates normal operation following initial acquisiti...

Page 16: ...ke sure the simulated COM port number is known to you Run the NAC1 GUI software Figure 7 NAC1 GUI Software The GUI enables simple communication to the NAC1 The GUI provides visual presentation of the...

Page 17: ...ST command description Appendix C Software ICD CLI The Disciplining dialog allows controlling the disciplining process The default setting is Enable Selecting Disable will disable the disciplining eff...

Page 18: ...of 7 6E 13 1 96E 10 or 4 98E 8 and can be positive or negative with an arbitrary number of steps Moreover corrections can be applied for the current session only until power down or forever In the lat...

Page 19: ...ion between the sidebands exactly equals the hyperfine frequency the vapor becomes transparent One uses this transparency to lock the local crystal oscillator that provides the clock output to the ato...

Page 20: ...C The NAC1 has two options for BIT status indication S W indication and H W indication 4 2 1 S W indication The CLI of the NAC1 contains the BIT indication The unit BIT can be remotely monitored by us...

Page 21: ...e the output driver circuit of the NAC1 is shown below in Figure 10 Figure 10 NAC1 10MHz Output Driver The NAC1 is designed for embedded low power applications i e it is expected to drive a high imped...

Page 22: ...ents with caution Uncontrolled frequency adjustments can result in a large frequency offset The internal frequency calibration of the NAC1 is set prior to shipment It is often desirable and likely tha...

Page 23: ...1PPS input is available the unit operates in the Hold Over mode To operate the disciplining mode connect a 1PPS source Section 4 8 to NAC1 Pin 9 and verify that the mode parameter of the SDM CLI comm...

Page 24: ...S input is applied and disciplining mode is activated SDM 1 2 1PPS input is applied and disciplining mode is activated SDM 1 3 1PPS input is not applied or disciplining mode is not activated SDM 0 Sta...

Page 25: ...oduces the SW indication that no 1PPS input is detected The SW waits for another two sequential cycles to determine that no 1PPS input exists and the NAC1 mode is set to Hold Over state 3 In case the...

Page 26: ...Document No ZD24010 Rev B2 NAC1 User Manual 26 of 38 6 Appendices Appendix A Mechanical ICD Figure 12 Mechanical ICD NAC1004...

Page 27: ...1 10MHz 3 3 VDC COM 1PPS OUT 1PPS IN BIT 10 1PPS Output CMOS compatible 3 3V 1M Rise Fall time 10 ns Pulse width 20 s 9 1PPS Input CMOS 3 3V 1M 4 Built in test BIT CMOS compatible 3 3V 1M 0 Normal ope...

Page 28: ...it 1 Data Bits 8 Stop Bit 1 Flow Control None Each setup command is used to 1 Set the appropriate parameters according to the full syntax 2 View the current system parameters in this case only the com...

Page 29: ...ation is to work with SEO N 6 If the communication is interactive with a user for example communication using a Hyper Terminal the recommendation is to work with SEO Y 7 a When SEO N is applied the ou...

Page 30: ...Commands Summary Command Name 1 VER Report Version 2 SEO Set Echo ON OFF 3 RST Reset Unit 4 RFC Rubidium Frequency Correct 5 SDM Set Disciplining Mode 6 SED Set External 1PPS input Propagation Delay...

Page 31: ...ample A1 Sn Serial number Up to 6 characters Example 000000 SW_Ver Software Version Up to 5 characters Example 01 00 FW_Ver Firmware Version Up to 5 characters Example 01 00 SEO Set Echo ON OFF SEO mo...

Page 32: ...value F Steps of 7 6E 13 will also be saved in a non volatile memory I Steps of 1 94E 10 will also be saved in a non volatile memory G Steps of 7 6E 13 will be saved in a volatile memory J Steps of 1...

Page 33: ...nput and will be in Hold Over mode SED Set External 1PPS input Propagation Delay Use this CLI command to set external 1PPS input propagation delay SED x x Delay in ns units Range 25 000 25 000ns Defau...

Page 34: ...le DPLL_Mode DPLL Loop 1 On 0 Off 1 Disciplining mode is enabled SDM 1 0 Disciplining mode is disabled SDM 0 N A Not Applicable FLL_mode FACTORY USE FLL Loop mode 1 On 0 Off DPLL_State DPLL state The...

Page 35: ...has been designed as a board mounted component NAC1 provides 10 MHz and 1PPS outputs and short term stability Allan Deviation of 2E 11 100 seconds with aging of 3E 10 month at 25 C The NAC1 has a RS2...

Page 36: ...V 1M Rise Fall time 10 ns Pulse width 20 s 1PPS Input CMOS 3 3V 1M Built in test BIT CMOS compatible 3 3V 1M 0 Normal operation 1 Alarm Power input 3 3 0 1 VDC Serial Comm Control and monitor interfac...

Page 37: ...range 1E 9 20 C to 65 C Digital Tuning Through Serial communication Range 2E 8 Resolution 7 6E 13 Initial offset at shipment 5E 11 Time Accuracy 1PPS Sync 100nsec Warm up Warm up Time Time to BIT 180...

Page 38: ...l 38 of 38 Special Features Wave Form Output Frequency AccuBeat P N Standard Square 10MHz NAC1004 Without pin 11 Square 10MHz NAC1C04 Description AccuBeat P N NAC1 Evaluation Kit AA50766 How to Order...