参数资料
型号: 5962-9169102M3A
厂商: CRYSTAL SEMICONDUCTOR CORP
元件分类: ADC
英文描述: 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CQCC28
封装: LCC-28
文件页数: 5/48页
文件大小: 647K
代理商: 5962-9169102M3A
Calibration
The ability of the CS5101A or the CS5102A to
convert accurately to 16-bits clearly depends on
the accuracy of its comparator and DAC. Each
device utilizes an "auto-zeroing" scheme to null
errors introduced by the comparator. All offsets
are stored on the capacitor array while in the
track mode and are effectively subtracted from
the input signal when a conversion is initiated.
Auto-zeroing enhances power supply rejection at
frequencies well below the conversion rate.
To achieve 16-bit accuracy from the DAC, the
CS5101A and CS5102A use a novel self-calibra-
tion scheme. Each bit capacitor shown in
Figure 1 actually consists of several capacitors in
parallel which can be manipulated to adjust the
overall bit weight. An on-chip micro controller
precisely adjusts each capacitor with a resolution
of 18 bits.
The CS5101A and CS5102A should be reset
upon power-up, thus initiating a calibration cycle.
The device then stores its calibration coefficients
in on-chip SRAM. When the CS5101A and
CS5102A are in power-down mode (SLEEP
low), they retain the calibration coefficients in
memory, and need not be recalibrated when nor-
mal operation is resumed.
OPERATION OVERVIEW
Monolithic design and inherent sampling archi-
tecture make the CS5101A and CS5102A
extremely easy to use.
Initiating Conversions
A falling transition on the HOLD pin places the
input in the hold mode and initiates a conversion
cycle. The charge is trapped on the capacitor ar-
ray the instant HOLD goes low. The device will
complete conversion of the sample within 66
master clock cycles, then automatically return to
the track mode. After allowing a short time for
acquisition, the device will be ready for another
conversion.
In contrast to systems with separate track-and-
holds and A/D converters, a sampling clock can
simply be connected to the HOLD input. The
duty cycle of this clock is not critical. The HOLD
input is latched internally by the master clock, so
it need only remain low for 1/fclk + 20 ns, but no
longer than the minimum conversion time minus
two master clocks or an additional conversion cy-
cle will be initiated with inadequate time for
acquisition. In Free Run mode, SCKMOD =
OUTMOD = 0, the device will convert at a rate
of CLKIN/80, and the HOLD input is ignored.
As with any high-resolution A-to-D system, it is
recommended that sampling is synchronized to
the master system clock in order to minimize the
effects of clock feedthrough. However, the
CS5101A and CS5102A may be operated entirely
asynchronous to the master clock if necessary.
Tracking the Input
Upon comp letin g a co nv ersion cycle the
CS5101A and CS5102A immediately return to
the track mode. The CH1/2 pin directly controls
the input switch, and therefore directly deter-
mines which channel will be tracked. Ideally, the
CH1/2 pin should be switched during the conver-
sion cycle, thereby nullifying the input mux
switching time, and guaranteeing a stable input at
the start of acquisition. If, however, the CH1/2
control is changed during the acquisition phase,
adequate coarse charge and fine charge time must
be allowed before initiating conversion.
When the CS5101A or the CS5102A enters track-
ing mode, it uses an internal input buffer
amplifier to provide the bulk of the charge on the
capacitor array (coarse-charge), thereby reducing
the current load on the external analog circuitry.
Coarse-charge is internally initiated for 6 clock
cycles at the end of every conversion. The buffer
CS5101A CS5102A
DS45F2
13
相关PDF资料
PDF描述
5962-9169202MXA 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CDIP28
5962-9169102MXA 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CDIP28
5962-9169201M3A 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CQCC28
5962-9169202M3A 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CQCC28
5962-9169101M3A 2-CH 16-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, CQCC28
相关代理商/技术参数
参数描述
5962-9169301M2A 制造商:Texas Instruments 功能描述:-LIFETIME BUYS TIL 03/03
5962-9169701MMA 制造商:e2v Aerospace & Defense 功能描述:SMD MKD 87C51RC-16 PHI-JLCC
5962-9169701MUA 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:Intel 功能描述:
5962-9169702MUA 制造商:Rochester Electronics LLC 功能描述:- Bulk
5962-9172201MEA 制造商:e2v 功能描述:Counter Single 4-Bit Binary UP 16-Pin CDIP 制造商:e2v technologies 功能描述:Counter Single 4-Bit Binary UP 16-Pin CDIP