參數(shù)資料
型號(hào): AS1538-BTST
廠商: AUSTRIAMICROSYSTEMS AG
元件分類: ADC
英文描述: 12-bit, 8-CH, 50ksps ADC, I2C; Package Type: TSSOP-16
封裝: TSSOP-16
文件頁(yè)數(shù): 16/20頁(yè)
文件大?。?/td> 746K
代理商: AS1538-BTST
www.austriamicrosystems.com
Revision 1.03
16 - 20
AS1538/AS1540
Data Sheet - Application Information
When using the internal reference:
1. Bit PD1 off the command byte must always be set to logic 1 for each sample conversion that is issued by the
sequence, as shown in
Figure 28 on page 14
.
2. In order to achieve 12-bit accuracy conversion when using the internal reference, the internal reference set-
tling time must be considered.
If bit PD1 has been set to logic 0 while using the AS1538/AS1540, then the settling time must be reconsidered
after PD1 is set to logic 1 (i.e., whenever the internal reference is turned on after it has been turned off, the set-
tling time must be long enough to get 12-bit accuracy conversion).
3. When the internal reference is off, it is not turned on until both the first command byte with PD1 = 1 is sent and
then a STOP condition or repeated START condition is issued. (The actual turn-on time occurs once the STOP
or repeated START condition is issued.) Any command byte with PD1 = 1 issued after the internal reference is
turned on serves only to keep the internal reference on. Otherwise, the internal reference would be turned off
by any command byte with PD1 = 0.
The example in
Figure 29
can be generalized for a conversion cycle by simply swapping the timing of the conversion
cycle.
Note:
If an external reference is used, PD1 must be set to 0, and the external reference must be settled. The typical
sequence in
Figure 28 on page 14
or
Figure 29 on page 15
can then be used.
Layout
For optimum performance, care should be taken with the physical layout of the AS1538/AS1540 circuitry. The basic
SAR architecture is sensitive to glitches or sudden changes on the power supply, reference, ground connections, and
digital inputs that occur just prior to latching the output of the analog comparator. Therefore, during any single conver-
sion for an
n
-bit SAR converter, there are
n
windows in which large external transient voltages can easily affect the
conversion result. Such glitches might originate from switching power supplies, nearby digital logic, and high-power
devices.
- Power to the AS1538/AS1540 should be clean and well-bypassed. A 0.1μF ceramic bypass capacitor should be
placed as close to the device as possible. A 1 to 10μF capacitor may also be needed if the impedance of the con-
nection between +V
DD
and the power supply is high.
- The AS1538/AS1540 architecture offers no inherent rejection of noise or voltage variation in regards to using an
external reference input. This is of particular concern when the reference input is tied to the power supply. Any
noise and ripple from the supply will appear directly in the digital results.
- While high-frequency noise can be filtered out, voltage variation due to line frequency (50 or 60Hz) can be difficult
to remove.
- The GND pin should be connected to a clean ground point. In many cases, this will be the analog ground. Avoid
connections that are too near the grounding point of a microcontroller or digital signal processor.
- The ideal layout will include an analog ground plane dedicated to the converter and associated analog circuitry.
Note:
For additional information download the evaluation board application note on our website.
相關(guān)PDF資料
PDF描述
AS1539-BTST 10-bit, 8-CH, 50ksps ADC, I2C; Package Type: TSSOP-16; Temperature Range: -40 - +85 °C; Output Interface: I"C; Supply Voltage: 2,70-5,50
AS1542-BTST 12-bit 16-CH 1Msps w Sequencer; Package Type: TSSOP-28
AS1543-BQFT 12-bit 8-CH 1Msps w Sequencer; Package Type: TQFN(4x4)-20
AS1545-BQFT Dual 12-bit, 12-CH, 1Msps; Package Type: TQFN(5x5)-32
AS1701-T 1.6W Audio Power Amplifiers ; Package Type: MSOP-8; Shutdown: Active High
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AS1538BTSU 制造商:AMS 功能描述:IC ADC 12BIT 50KSPS TSSOP-16 制造商:AMS 功能描述:IC, ADC, 12BIT, 50KSPS, TSSOP-16 制造商:AMS 功能描述:IC, ADC, 12BIT, 50KSPS, TSSOP-16; Resolution (Bits):12bit; Sampling Rate:50kSPS; Supply Voltage Type:Single; Supply Voltage Min:2.7V; Supply Voltage Max:5.25V; Supply Current:850A; Digital IC Case Style:TSSOP; No. of Pins:16 ;RoHS Compliant: Yes
AS1538-BTSU 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32
AS1538-EB 制造商:ams 功能描述:AS1538 Evaluation Board
AS1538-TS_EK_ST 功能描述:AS1538 - 12 Bit 50k Samples per Second Analog to Digital Converter (ADC) Evaluation Board 制造商:ams 系列:- 零件狀態(tài):過(guò)期 A/D 轉(zhuǎn)換器數(shù):1 位數(shù):12 采樣率(每秒):50k 數(shù)據(jù)接口:I2C 輸入范圍:±0.3 V 不同條件下的功率(典型值):- 使用的 IC/零件:AS1538 所含物品:板 標(biāo)準(zhǔn)包裝:1
AS1539 制造商:AMSCO 制造商全稱:austriamicrosystems AG 功能描述:8/4-Channel, 10-Bit IC Analog-to-Digital Converter