TC7109 TelCom, TC7109 Datasheet - Page 21

• Manufacturer Part Number: TC7109
• Description: 12-BIT UP-COMPATIBLE ANALOG-TO-DIGITAL CONVERTERS
• Manufacturer: TelCom

12-BIT P-COMPATIBLE
ANALOG-TO-DIGITAL CONVERTERS
Integrating Converter Features
or average, of an input voltage over a fixed period of time.
Compared with techniques in which the input is sampled and
held, the integrating converter averages the effects of noise.
A second important characteristic is that time is used to
quantize the answer, resulting in extremely small nonlinearity
errors and no missing output codes. The integrating con-
verter also has very good rejection of frequencies whose
periods are an integral multiple of the measurement period.
This feature can be used to advantage in reducing line
frequency noise (Figure 22).
ANALOG
The output of integrating ADCs represents the integral,
TELCOM SEMICONDUCTOR, INC.
IN
HBEN
MODE CE/
TC7109A
LOAD
RUN/HOLD
POL, OR
B9–B12
SEND
LBEN
B1-B8
TBRL DRR
6
8
Figure 21.
+5V
ANALOG
TBRE
Handshake Interface for Multiplexed Converters
IN
6402 CMOS UART
RBR1–RBR8
2
MODE CE/
HBEN
8-BIT DATA BUS
TC7109A
LOAD
RUN/HOLD
3
POL, OR
Figure 22. Normal Mode Rejection of Dual-Slope Converter as a
B9–B12
SEND
LBEN
B1–B8
GND
SFD
SERIAL OUTPUT
30
20
10
TBR1–TBR8
SERIAL INPUT
0
0.1/t
6
8
Function of Frequency
+5V
t = MEASUREMENT
PERIOD
ANALOG
IN
INPUT FREQUENCY
MODE CE/
HBEN
1/t
TC7109A
LOAD
RUN/HOLD
POL, OR
B9–B12
SEND
LBEN
B1–B8
TC7109A
TC7109
6
8
10/t
+5V
3-111
1
2
3
4
5
6
7
8