参数资料
型号: TC7116ACLWRT
元件分类: ADC
英文描述: 1-CH DUAL-SLOPE ADC, ACCESS, PQCC44
封装: PLASTIC, LCC-44
文件页数: 15/17页
文件大小: 221K
代理商: TC7116ACLWRT
7
3-1/2 DIGIT ANALOG-TO-DIGITAL
CONVERTERS WITH HOLD
TC7116
TC7116A
TC7117
TC7117A
Reference Integrate Phase
The final phase is reference integrate, or deintegrate.
Input low is internally connected to analog common and
input high is connected across the previously charged
reference capacitor. Circuitry within the chip ensures that
the capacitor will be connected with the correct polarity to
cause the integrator output to return to zero. The time
required for the output to return to zero is proportional to
the input signal. The digital reading displayed is:
TC7116
TC7116A
TC7117
TC7117A
CREF
C REF
BUFF
CREF
RINT
V
+
CAZ
AUTO-
ZERO
VINT
28
35
29
27
33
36
34
10 A
31
A/Z
INT
A/Z & DE (±)
32
30
INT
26
INTEGRATOR
V
+
–3V
COMPARATOR
TO
DIGITAL
SECTION
DE (+)
DE
(–)
DE
(+)
DE (–)
V
+
A/Z
ANALOG
COMMON
+
V IN
+
V IN
V
CINT
VREF
+
LOW
TEMP
DRIFT
ZENER
VREF
V
+
+
+
ANALOG SECTION
(All Pin designations refers to 40-Pin DIP)
Figure 3 shows the block diagram of the analog section
for the TC7116/TC7116A and TC7117/TC7117A. Each
measurement cycle is divided into three phases: (1) auto-
zero (A-Z), (2) signal integrate (INT), and (3) reference
integrate (REF) or deintegrate (DE).
Auto-Zero Phase
High and low inputs are disconnected from the pins
and internally shorted to analog common. The reference
capacitor is charged to the reference voltage. A feedback
loop is closed around the system to charge the auto-zero
capacitor (CAZ) to compensate for offset voltages in the
buffer amplifier, integrator, and comparator. Since the com-
parator is included in the loop, A-Z accuracy is limited only
by system noise. The offset referred to the input is less
than 10
V.
Signal-Integrate Phase
The auto-zero loop is opened, the internal short is
removed, and the internal high and low inputs are con-
nected to the external pins. The converter then integrates
the differential voltages between V
+
IN and V
IN for a fixed
time. This differential voltage can be within a wide com-
mon-mode range; 1V of either supply. However, if the input
signal has no return with respect to the converter power
supply, V
IN can be tied to analog common to establish the
correct common-mode voltage. At the end of this phase,
the polarity of the integrated signal is determined.
Figure 3. Analog Section of TC7116/TC7116A and TC7117/TC7117A
1000
×
.
VIN
VREF
Reference
The positive reference voltage (V
+
REF) is referred to
analog common.
Differential Input
This input can accept differential voltages anywhere
within the common-mode range of the input amplifier or,
specifically, from 1V below the positive supply to 1V above
the negative supply. In this range, the system has a CMRR
of 86 dB, typical. However, since the integrator also swings
with the common-mode voltage, care must be exercised to
ensure that the integrator output does not saturate. A
worst- case condition would be a large, positive common-
mode voltage with a near full-scale negative differential
input voltage. The negative-input signal drives the integra-
tor positive when most of its swing has been used up by the
positive common-mode voltage. For these critical applica-
相关PDF资料
PDF描述
TC7116CLWRT 1-CH DUAL-SLOPE ADC, ACCESS, PQCC44
TC7116CLWTR 1-CH 13-BIT DUAL-SLOPE ADC, PQCC44
TC7116CLW 1-CH 13-BIT DUAL-SLOPE ADC, ACCESS, PQCC44
TC7116CKW 1-CH 13-BIT DUAL-SLOPE ADC, ACCESS, PQFP44
TC7117AIJL 1-CH 13-BIT DUAL-SLOPE ADC, ACCESS, CDIP40
相关代理商/技术参数
参数描述
TC7116ACPL 功能描述:LCD 驱动器 w/Hold RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TC7116AIJL 功能描述:LCD 驱动器 3-1/2 Digit A/D w/ Hold RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TC7116CKW 功能描述:LCD 驱动器 w/Hold RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TC7116CKW713 功能描述:LCD 驱动器 w/Hold RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TC7116CLW 功能描述:LCD 驱动器 w/Hold RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube