44
45
46
47
48
49
50
SLEEP
FREQ
O
I
I
O
O
O
Sleep mode indicator, asserts low in SLEEP mode.
Frequency counter input, offset V-/2 internally by the chip.
Assert low to enable serial data output.
Filter capacitor connection for resistance mode.
Filter capacitor connection for resistance mode.
LCD segment line 17
RS232
OHMC2
OHMC3
SEG17
NC
51 - 66 SEG16 – SEG01
O
O
O
O
O
O
LCD segment line 01 – 16
LCD backplane 4
LCD backplane 3
LCD backplane 2
67
68
69
70
71
BP4
BP3
BP2
BP1
LCD backplane 1
ANNUNC
Square wave output at the backplane frequency, synchronized to
BP1. ANNUNC can be used to control display annunciator. Connect a
LCD segment to ANNUNC to turn it on; connect an LCD segment to
its backplane to turn it off.
72
73
BUZIN
BUZOUT
I
O
Pull to V- to enable the BUZOUT.
Outputs a 2KHz audio frequency signal for driving piezoelectric buzze
when BUZIN is low.
74
BKOUT
O
If BKLIT function is enabled, this pin will change from –3V to +3V
For 60 sec, once press BKLIT pin again within 60 sec, this pin will
Change back to –3V.
75
76
77
78
79
80
81
82
83
84
85
86
MAXMIN
VAHZ
NC
REL_ZERO
HOLD
RANGE
OSC1
OSC2
APOSEL
CESEL
BKLIT
KEY
I
I
Pulse to V- to enable MAX/MIN function.
Pulse to V- to enable VAHZ mode.
I
I
I
I
O
I
I
I
I
Pulse to V- to enable Relative function or Zero function.
Pulse to V- to enable HOLD function.
Pulse to V- to enable manual mode and manual range selection.
Crystal oscillator input connection
Crystal oscillator output connection
Idle time selection for auto power off feature.
CE selection feature control pin.
Back light function. Pulse low to set BKOUT pin output.
Pulse to V- to change mode. In ADP mode, if this pin is connected to
V-, the buzzer output will be off when the ADP input overflows.
Select initial state. Please refer to page 13
Switch 5 for function selection.
Switch 4 for function selection.
Switch 3 for function selection.
Switch 2 for function selection.
Switch 1 for function selection.
Low battery configuration. If 3V battery is used, connect it to AGND.
The default low-battery threshold voltage is –2.3V. If 9V battery is
Used, the low battery annunciator is displayed when the voltage of
this pin is less than VRH (-1.2V)
87
88
89
90
91
92
93
SLACDC
FC5
I
I
I
I
I
I
I
FC4
FC3
FC2
FC1
LBAT9
94
95
96
SDO
C+
C-
O
O
O
P
RS232 compliant serial data output.
Positive capacitor connection for on-chip DC-DC converter.
Negative capacitor connection for on-chip DC-DC converter.
Negative supply voltage. Connecting to 3V battery negative terminal.
97
V-
98
99
100
DGND
AGND
AGND
P/G Digital ground. Connecting to 3V battery positive terminal.
P/G Analog ground.
P/G Analog ground.
v1.2
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11/09/06
CYRUSTEK [ Cyrustek corporation ]
