参数资料
型号: MAX1270ACAI
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: ADC
英文描述: Multirange, +5V, 8-Channel, Serial 12-Bit ADCs
中文描述: 8-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDSO28
封装: 5.3 MM, 0.65 MM PITCH, MO-150, SSOP-28
文件页数: 16/20页
文件大小: 808K
代理商: MAX1270ACAI
M
Multirange, +5V, 8-Channel,
Serial 12-Bit ADCs
16
______________________________________________________________________________________
Power-Down Mode
To save power, configure the converter into low-current
shutdown mode between conversions. Two program-
mable power-down modes are available in addition to a
hardware shutdown. Select STBYPD or FULLPD by pro-
gramming PD0 and PD1 in the input control byte
(Table 4). When software power-down is asserted, it
becomes effective only after the end of conversion. For
example, if the control byte contains PD1 = 0, then the
chip remains powered up. If PD1 = 1, then the chip
powers down at the end of conversion. In all power-
down modes, the interface remains active and conver-
sion results can be read. Input overvoltage protection is
active in all power-down modes.
The first logical 1 on DIN after
CS
falls is interpreted as
a start condition, and powers up the MAX1270/
MAX1271 from a software selected STBYPD or FULLPD
condition.
For hardware-controlled power-down (FULLPD), pull
SHDN low. When hardware shutdown is asserted, it
becomes effective immediately, and any conversion in
progress is aborted.
Choosing Power-Down Modes
The bandgap reference and reference buffer remain
active in STBYPD mode, maintaining the voltage on the
4.7μF capacitor at REF. This is a DC state that does not
degrade after power-down of any duration.
In FULLPD mode, only the bandgap reference is active.
Connect a 33μF capacitor between REF and AGND to
maintain the reference voltage between conversions
and to reduce transients when the buffer is enabled
and disabled. Throughput rates down to 1ksps can be
achieved without allotting extra acquisition time for ref-
erence recovery prior to conversion. This allows con-
version to begin immediately after power-up. If the
discharge of the REF capacitor during FULLPD
exceeds the desired limits for accuracy (less than a
fraction of an LSB), run a STBYPD power-down cycle
prior to starting conversions. Take into account that the
reference buffer recharges the bypass capacitor at an
80mV/ms slew rate, and add 50μs for settling time.
Auto-Shutdown
Selecting STBYPD on every conversion automatically
shuts down the MAX1270/MAX1271 after each conversion
without requiring any start-up time on the next conversion.
REF
10k
2.5V
2.5V
REFADJ
A
V
= 1.638
MAX1270
MAX1271
4.7
μ
F
C
REF
0.01
μ
F
Figure 13c. External Reference—Reference at REFADJ
REF
V
DD
10k
2.5V
4.096V
REFADJ
A
V
= 1.638
MAX1270
MAX1271
4.7
μ
F
C
REF
Figure 13b. External Reference—Reference at REF
REF
10k
2.5V
REFADJ
0.01
μ
F
A
V
= 1.638
MAX1270
MAX1271
4.7
μ
F
C
REF
Figure 13a. Internal Reference
相关PDF资料
PDF描述
MAX1270ACNG Multirange, +5V, 8-Channel, Serial 12-Bit ADCs
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MAX1271ACAI Multirange, +5V, 8-Channel, Serial 12-Bit ADCs
MAX1271ACNG Multirange, +5V, 8-Channel, Serial 12-Bit ADCs
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相关代理商/技术参数
参数描述
MAX1270ACAI+ 功能描述:模数转换器 - ADC 12-Bit 8Ch 110ksps 4.18V Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX1270ACAI+T 功能描述:模数转换器 - ADC 12-Bit 8Ch 110ksps 4.18V Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX1270ACAI-T 功能描述:模数转换器 - ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX1270ACNG 功能描述:模数转换器 - ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32
MAX1270ACNG+ 功能描述:模数转换器 - ADC 12-Bit 8Ch 110ksps 4.18V Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32