参数资料
型号: MAX186ACPP
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: ADC
英文描述: Low-Power, 8-Channel, Serial 12-Bit ADCs
中文描述: 8-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP20
封装: PLASTIC, DIP-20
文件页数: 18/24页
文件大小: 245K
代理商: MAX186ACPP
M
Lowest Power at Higher Throughputs
Figure 14b shows the power consumption with
external-reference compensation in fast power-down,
with one and eight channels converted. The external
4.7μF compensation requires a 50μs wait after power-up,
accomplished by 75 idle clocks after a dummy conver-
sion. This circuit combines fast multi-channel conversion
with lowest power consumption possible. Full
power-down mode may provide increased power sav-
ings in applications where the MAX186/MAX188 are
inactive for long periods of time, but where intermittent
bursts of high-speed conversions are required.
External and Internal Referenc es
The MAX186 can be used with an internal or external
reference, whereas an external reference is required for
the MAX188. Diode D1 shown in the Typical Operating
Circuit ensures correct start-up. Any standard signal
diode can be used. For both parts, an external refer-
ence can either be connected directly at the VREF ter-
minal or at the REFADJ pin.
An internal buffer is designed to provide 4.096V at
VREF for both the MAX186 and MAX188. The
MAX186’s internally trimmed 2.46V reference is
buffered with a gain of 1.678. The MAX188's buffer is
trimmed with a buffer gain of 1.638 to scale an external
2.5V reference at REFADJ to 4.096V at VREF.
MAX186 Internal Reference
The full-scale range of the MAX186 with internal reference
is 4.096V with unipolar inputs, and ±2.048V with bipolar
inputs. The internal reference voltage is adjustable to
±1.5% with the Reference-Adjust Circuit of Figure 17.
External Reference
With both the MAX186 and MAX188, an external refer-
ence can be placed at either the input (REFADJ ) or the
output (VREF) of the internal buffer amplifier. The
REFADJ input impedance is typically 20k
for the
MAX186 and higher than 100k
for the MAX188, where
the internal reference is omitted. At VREF, the input
impedance is a minimum of 12k
for DC currents.
During conversion, an external reference at VREF must
be able to deliver up to 350μA DC load current and have
an output impedance of 10
or less. If the reference has
higher output impedance or is noisy, bypass it close to
the VREF pin with a 4.7μF capacitor.
Low-Power, 8-Channel,
S erial 12-Bit ADCs
18
______________________________________________________________________________________
1000
1
0
100
300
500
MAX186
FULL POWER-DOWN
10
100
M
CONVERSIONS PER CHANNEL PER SECOND
200
400
2ms FASTPD WAIT
400kHz EXTERNAL CLOCK
INTERNAL COMPENSATION
50
150
250
350
450
8 CHANNELS
1 CHANNEL
A
10,000
10
0
MAX186/MAX188
FAST POWER-DOWN
100
1000
CONVERSIONS PER CHANNEL PER SECOND
2k
8 CHANNELS
1 CHANNEL
4k
6k
8k
10k
12k
14k
16k
18k
2MHz EXTERNAL CLOCK
EXTERNAL COMPENSATION
50μs WAIT
A
Figure 14a. MAX186 Supply Current vs. Sample Rate/Second,
FULLPD, 400kHz Clock
Figure 14b. MAX186/MAX188 Supply Current vs. Sample
Rate/Second, FASTPD, 2MHz Clock
3.0
2.5
2.0
1.5
1.0
0.5
0
0.0001
0.001
0.01
0.1
1
10
TIME IN SHUTDOWN (sec)
P
Figure 14c. Typical Power-Up Delay vs. Time in Shutdown
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相关代理商/技术参数
参数描述
MAX186ACPP+ 功能描述:模数转换器 - ADC 12-Bit 8Ch 133ksps 5.25V 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
MAX186ACWP 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
MAX186ACWP+ 功能描述:模数转换器 - ADC 12-Bit 8Ch 133ksps 5.25V 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
MAX186ACWP+T 功能描述:模数转换器 - ADC 12-Bit 8Ch 133ksps 5.25V 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
MAX186ACWP-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