Rainbow Electronics ADC12181 - Manual (Page 3)

Pin Descriptions and Equivalent Circuits #2
No. Symbol Equivalent Circuit Description
2 V
IN
Analog signal input. With a 2.0V reference voltage,
input signal voltages in the range of 0 to 2.0 Volts
will be converted. See section 1.2.
1 V
REF
Reference voltage input. This pin should be driven
from an accurate, stable reference source in the
range of 1.8 to 2.2V and bypassed to a low-noise
analog ground with a monolithic ceramic capacitor,
nominally 0.01µF. See section 1.1.
32 V
RP
Positive reference bypass pin. Bypass with a 0.1µF
capacitor. Do not connect anything else to this pin.
See section 3.1
31 V
RM
Reference midpoint bypass pin. Bypass with a 0.1µF
capacitor. Do not connect anything else to this pin.
See section 3.1
30 V
RN
Negative reverence bypass pin. Bypass with a 0.1µF
capacitor. Do not connect anything else to this pin.
See section 3.1
10 CLOCK
Sample Clock input, TTL compatible. Maximum
amplitude should not exceed 3V.
8 CAL
Calibration request, active High. Calibration cycle
starts when CAL returns to logic low. CAL is ignored
during power-down mode. See section 2.2.
7 PD
Power-down, active High, ignored during calibration
cycle. See paragraph 2.4
11 OE
Output enable control, active low. When this pin is
high the data outputs are in Tri-state
(high-impedance) mode.
28 OR
Over range indicator. This pin is at a logic High for
V
IN
< 0 or for V
IN
> V
REF
.
29 READY
Device ready indicator, active High. This pin is at a
logic Low during a calibration cycle and while the
device is in the power down mode.
ADC12181
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