UBX-G7020 - Hardware Integration Manual
Component Selection
GPS.G7-HW-10003 Objective Specification Page 50 of 74
3.2 Crystal (Y2)
Parallel Resonance, Fundamental Mode
Nominal frequency at 25 ± 3 ºC
6
26 MHz (other frequencies possible, see datasheet
7
)
Frequency calibration tolerance at 25 ± 3 ºC
8
Frequency stability over operating temperature range
referenced to frequency reading 25 ± 3 ºC
9
Operating temperature range
Frequency perturbations
10
Static temperature hysteresis
11
Short term stability, root Allan variance ( = 1 s)
Long term stability, frequency drift over 1 year
Long term stability, frequency drift over 2 years
Long term stability, frequency drift over 10 years
G Sensitivity, all 3 axes, random vibration, 30 Hz to 1.5 kHz
Shock, frequency shift after 1000G 250 µs sine
Electrical Specifications
Equivalent circuit (shunt) capacitance C
0
Maximum Drive Level (only at oscillator start-up, if required)
10 - 80 µW, corresponding to 10 – 50 mV
Drive level dependency (DLD)
12
Equivalent series resistance (ESR)
Electrical Specifications
Half sine wave acceleration of 100 G peak amplitude for 11 ms
duration, 3 cycles each plane
10 G RMS 30 Hz to 1500 Hz, duration of 6 hours
48 hours at 85 °C 85% relative humidity non-condensing
Exposed at –40 °C for 30 minutes then to 85 °C for 30 minutes
constantly for 120 cycles (5 days)
Manufacturing Information
Able to withstand solder reflow process, min. 3 Cycles (240 °C,
20 s)
Table 15: GPS crystal specifications
IEC19RSX-8 26.000MHz XZC918
IEC19RSX−10 26.000 MHz XZD182
Table 16: Recommend parts list for GPS reference crystal
6
A reference temperature can be defined with crystal supplier within this range.
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UBX-G7020-Kx Data Sheet [1] and UBX-G7020-CT Data Sheet [2].
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Same reference temperature as in 2.2
9
Same reference temperature as in 2.2
10
Peak to peak deviation from the frequency versus AT temperature curve fit. Minimum of 1 frequency reading every 3 °C over operating
temperature range. 100% testing and screening for frequency perturbations and micro jump occurrence.
11
Frequency change after reciprocal temperature ramped over the operating temperature range. Frequency measured before and after at
25 °C.
12
Resistance change of 10 different power levels from 0.001 µW to 100 µW