参数资料
型号: MAX1295ACEI
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: ADC
英文描述: 265ksps, +3V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface
中文描述: 6-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, PARALLEL ACCESS, PDSO28
封装: 0.150 INCH, QSOP-28
文件页数: 15/20页
文件大小: 228K
代理商: MAX1295ACEI
M
265ksps, +3V, 6-/2-Channel, 12-Bit ADCs
with +2.5V Reference and Parallel Interface
______________________________________________________________________________________
15
Shutdown Mode
Shutdown mode turns off all chip functions that draw qui-
escent current, reducing the typical supply current to
2μA immediately after the current conversion is complet-
ed. A rising edge on
WR
causes the MAX1295/MAX1297
to exit shutdown mode and return to normal operation.
To achieve full 12-bit accuracy with a 4.7μF reference
bypass capacitor, 50μs is required after power-up.
Waiting this 50μs in standby mode instead of in full-
power mode can reduce power consumption by a factor
of 3 or more. When using an external reference, only
50μs is required after power-up. Enter standby mode by
performing a dummy conversion with the control byte
specifying standby mode.
Note:
Bypass capacitors larger than 4.7μF between
REF and GND will result in longer power-up delays.
Transfer Function
Table 5 shows the full-scale voltage ranges for unipolar
and bipolar modes. Figure 8 depicts the nominal unipo-
lar input/output (I/O) transfer function, and Figure 9
shows the bipolar I/O transfer function. Code transitions
occur halfway between successive-integer LSB values.
Output coding is binary, with 1LSB = (V
REF
/4096).
Maximum Sampling Rate/
Achieving 300ksps
When running at the maximum clock frequency of
4.8MHz, the specified throughput of 265ksps is achieved
by completing a conversion every 18 clock cycles: 1
write cycle, 3 acquisition cycles, 13 conversion cycles,
and 1 read cycle. This assumes that the results of the
last conversion are read before the next control byte is
written. It is possible to achieve higher throughputs, up
to 300ksps, by first writing a control byte to begin the
Table 5. Full-Scale and Zero-Scale for Unipolar and Bipolar Operation
111
. . .
111
111
. . .
110
100
. . .
010
100
. . .
001
100
. . .
000
011
. . .
111
011
. . .
110
011
. . .
101
000
. . .
001
000
. . .
000
1
0
INPUT VOLTAGE (LSB)
OUTPUT CODE
ZS = COM
FS = REF + COM
1LSB = 4096
FULL-SCALE
TRANSITION
(COM)
FS - 3/2LSB
FS
2
2048
UNIPOLAR MODE
BIPOLAR MODE
V
REF
+ COM
COM
V
REF
/2 + COM
COM
-V
REF
/2 + COM
Positive Full Scale
Zero Scale
Negative Full Scale
Full Scale
Zero Scale
Figure 8. Unipolar Transfer Function
011
. . .
111
011
. . .
110
000
. . .
010
000
. . .
001
000
. . .
000
111
. . .
111
111
. . .
110
111
. . .
101
100
. . .
001
100
. . .
000
- FS
COM*
INPUT VOLTAGE (LSB)
OUTPUT CODE
ZS = COM
+FS - 1LSB
*COM V
REF
/2
+ COM
FS
= REF
2
-FS =
+ COM
-REF
2
REF
4096
1LSB =
Figure 9. Bipolar Transfer Function
相关PDF资料
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MAX1295BCEI 265ksps, +3V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface
MAX1297 265ksps, +3V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface
MAX1295AEEI 265ksps, +3V, 6-/2-Channel, 12-Bit ADCs with +2.5V Reference and Parallel Interface
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相关代理商/技术参数
参数描述
MAX1295ACEI+ 功能描述:模数转换器 - ADC 12-Bit 6Ch 265ksps 3.6V 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
MAX1295ACEI+T 功能描述:模数转换器 - ADC 12-Bit 6Ch 265ksps 3.6V 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
MAX1295ACEI-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
MAX1295AEEI 功能描述:模数转换器 - ADC Integrated Circuits (ICs) 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
MAX1295AEEI+ 功能描述:模数转换器 - ADC 12-Bit 6Ch 265ksps 3.6V 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