参数资料
型号: TLC545ING4
厂商: TEXAS INSTRUMENTS INC
元件分类: ADC
英文描述: 19-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP28
封装: PLASTIC, DIP-28
文件页数: 15/15页
文件大小: 202K
代理商: TLC545ING4
TLC545C, TLC545I, TLC546C, TLC546I
8-BIT ANALOG-TO-DIGITAL CONVERTERS
WITH SERIAL CONTROL AND 19 INPUTS
SLAS066B – DECEMBER 1985 – REVISED OCTOBER 1996
9
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
simplified analog input analysis
Using the equivalent circuit in Figure 1, the time required to charge the analog input capacitance from 0 to VS
within 1/2 LSB can be derived as follows:
The capacitance charging voltage is given by
VC = VS 1–e
–t c/RtCi
(
)
(1)
where
Rt = Rs + ri
The final voltage to 1/2 LSB is given by
(2)
VC (1/2 LSB) = VS – (VS/512)
Equating equation 1 to equation 2 and solving for time tc gives
VS –(VS/512) = VS 1–e
(
)
(3)
–t c/RtCi
and
tc (1/2 LSB) = Rt × Ci × ln(512)
(4)
Therefore, with the values given the time for the analog input signal to settle is
(5)
tc (1/2 LSB) = (Rs + 1 k) × 60 pF × ln(512)
This time must be less than the converter sample time shown in the timing diagrams.
VI = Input Voltage at INPUT A0 – A18
VS = External Driving Source Voltage
Rs = Source Resistance
ri = Input Resistance
Ci = Input Capacitance
Driving source requirements:
Noise and distortion for the source must be equivalent to the
resolution of the converter.
Rs must be real at the input frequency.
Rs
ri
VS
VC
50 pF MAX
1 k
MAX
Driving Source
TLC545 / 6
Ci
VI
Figure 1. Equivalent Input Circuit Including the Driving Source
相关PDF资料
PDF描述
TLC545CFN 19-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PQCC28
TLC546IN 19-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP28
TLC545IFN 19-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PQCC28
TLC545IN 19-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP28
TLC548CP 1-CH 8-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP8
相关代理商/技术参数
参数描述
TLC546C 制造商:TI 制造商全称:Texas Instruments 功能描述:8-BIT ANALOG-TO-DIGITAL CONVERTERS WITH SERIAL CONTROL AND 19 INPUTS
TLC546I 制造商:TI 制造商全称:Texas Instruments 功能描述:8-BIT ANALOG-TO-DIGITAL CONVERTERS WITH SERIAL CONTROL AND 19 INPUTS
TLC546IFN 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:Texas Instruments 功能描述:
TLC546IN 制造商:Rochester Electronics LLC 功能描述:- Bulk
TLC548 制造商:TI 制造商全称:Texas Instruments 功能描述:8-BIT ANALOG-TO-DIGITAL CONVERTERS WITH SERIAL CONTROL