CYRUSTEK CO.
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TEST
. Thus TEST may be used
The TEST pin is tied to the internally generated digital supply. It’s potential is 5V less than
as the negative power supply connection for externally generated segment drivers.
If TEST is pulled low to
all segments plus the minus sign will be activated and the display should read -1888. For
such operation, the segment has a constant DC voltage and may destroy the LCD display if left in this mode for several
minutes.
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Frequency Counter
The ES5108 provides 2KHz to 2MHz five-decade auto-range frequency counter. In the counter mode, pulses at the
FREQ-IN will be counted and displayed. The frequency counter derives its time base from the clock oscillator and gets
one readout persecond. The frequency counter accuracy is determined by the oscillator accuracy. For accurate frequency
measurement, a 40KHz quartz crystal oscillator is recommended.
The decimal points are automatically set to frequency mode.See following table :
FREQ-IN
0KHz to 1.999KHz
2.0KHz to 19.99KHz
20KHz to 199.9KHz
200KHz to 1999KHz
2.0MHz to 19.99MHz
20MHz or more
Decimal point Annunciator
DP3
KHz
DP2
KHz
DP1
KHz
NONE
KHz
DP2
MHz
DISPLAY "OL"
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Hold, MAX and MAX/MIN
"Hold" function will hold the current readout and converter operation.
"MAX" function in ES5108L will display the maximum value.
"MAX/MIN" function in ES5108D has two mode : MAX and MIN. When the MAX/MIN is pressed for the first time, the
meter displays the maximum value. When the MAX/MIN is pressed again, the meter displays the minimum value. The
meter returns to normal mode if the MAX/MIN is pressed more then one seconds.
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Serial data output
the ES5108 provides serial data output for use in connection with microcontrollers. During this operation, ES5108 uses
CLK, SDO and EOC pins. The following is the timing diagram of this connection.
The EOC pin will be pulled HIGH at the end of conversion and the content of serial output data buffer will update simul-
taneously.
The waveform of EOC pin will go LOW as soon as CLK pin receives clock signal.Otherwise the EOC pin will stay HIGH
and then go LOW in 10ms.
Serial data output format :
D15
LSB
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
MSB
1. Voltage Mode :
(a) D0(Polarity) : ’1’ for ’+’ and ’0’ for ’-’
(b) D1(MSD) : ’1’ for MSD = 1 and ’0’ for MSD = 0
(c) D2 to D5 for 3rd LSD(from 0000 to 1001).
(d) D6 to D9 for 2nd LSD(from 0000 to 1001).
(e) D10 to D13 for 1st LSD(from 0000 to 1001).
(f) D14 and D15 for decimal points bits : ’00’ for none, ’01’ for DP1, ’10’ for DP2, ’11’ for DP3.
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November 23, 2006
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ES5108
3 1/2 Digit
ADC with serial output
CYRUSTEK [ Cyrustek corporation ]
