ES51964(6600counts)
Dual Display
2.9 Frequency counter
In frequency mode, main-display shows frequency and sub-display shows duty cycle at the
same time. The time base of the frequency counter is derived from an external crystal
oscillator by
4,000,000
Tcounter
=
Fosc
where Fosc is the frequency of the crystal oscillator. Thus, the counter has a 1-second time
base when a 4MHz oscillator is used. The frequency counter can select the proper range
automatically or manually. Auto-range operation extends over seven decades, from 66.00Hz
to 66.00MHz. The following table summarizes the full-scale range of the frequency counter.
Range
FR1*
FR2
Full Scale
66.00Hz
660.0Hz
FR3
FR4
FR5
FR6
6.600KHz
66.00KHz
660.0KHz
6.600MHz
66.00MHz
FR7
*If input frequency is less than 6.0Hz, ES51964 will show 0.00Hz.
2.10 Temperature measurement mode
Temperature measurement mode takes input signal from ADP pin and reference voltage
from (VA+ - VA-). ES51964 has a built-in ºC-to-ºF scale translation circuit, and only needs
an external ºC scale application circuit. The application circuit for ºF scale is not required.
In temperature measurement mode, the default range is 6600 ºC or 9999 ºF. The VBAR pin
is used to control the first decimal point (DP1) on the LCD panel. When VBAR is pulled to
V-, DP1 will be turned on and the full scale becomes 660.0 ºC or 999.9 ºF.
2.11 Duty Cycle measurement
The duty cycle measurement is available in frequency mode simultaneously. The duty cycle
mode range is within 1.00% to 98.90% (< 10kHz@3Vpp). The minimum resolution is
0.01%. If the source frequency duty cycle is smaller than 0.9%, the 0.00% will be shown on
the LCD display. If the duty cycle is larger than 98.9%, the OL will be shown on the LCD
sub-display. If the SHIFT pin (pin 111) is pulled to V-, a display-shifted feature is available
for duty-cycle mode. The minimum resolution is 0.1% when SHIFT is active. When the
frequency is zero, the duty cycle display will be 0.00% or OL shown.
v2.5
12
09/04/14
CYRUSTEK [ Cyrustek corporation ]
