SM77 -M  
       Nominal Frequency in MHz
       Nominal Power Supply Voltage
V = +3.3V
W = +2.5V
X = +1.8V
Y = +5.0V (if temperature range is 'E' the 'Y' is often deleted)
       Temperature Range
= -10°C to +70°C
E = -40°C to +85°C
       Product Option
D = 70MHz and higher
G = Below 70MHz optimized for larger loads (long lead times)
H = Below 70MHz Standard (most stocked parts)
M = Below 70MHz optimized for lowest power (long lead times)
       Frequency Stability
20 = ±20ppm over the temperature range, supply, load and aging
44 = ±25ppm over the temperature range, supply, load and aging
45 = ±50ppm over the temperature range, supply, load and aging
       Model CMOS Output 5.0 x 7.0mm LCC
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