MAX1248/MAX1249
+2.7V to +5.25V, Low-Power, 4-Channel,
Serial 10-Bit ADCs in QSOP-16
Lowest Power at Higher Throughputs
Figure 13b shows the power consumption with
external-reference compensation in fast power-down,
with one and four channels converted. The external
4.7F compensation requires a 75s wait after power-up
with one dummy conversion. This circuit combines fast
multi-channel conversion with lowest power consumption
possible. Full power-down mode may provide increased
power
savings
in
applications
where
the
MAX1248/MAX1249 are inactive for long periods of time,
but where intermittent bursts of high-speed conversions
are required.
Internal and External References
The MAX1248 can be used with an internal or external
reference voltage, whereas an external reference is
required for the MAX1249. An external reference can
be connected directly at VREF or at the REFADJ pin.
An internal buffer is designed to provide 2.5V at VREF
for both the MAX1248 and the MAX1249. The
MAX1248’s internally trimmed 1.21V reference is
buffered with a gain of 2.06. The MAX1249’s REFADJ
pin is also buffered with a gain of 2.06 to scale an
external 1.25V reference at REFADJ to 2.5V at VREF.
Internal Reference (MAX1248)
The MAX1248’s full-scale range with the internal refer-
ence is 2.5V with unipolar inputs and ±1.25V with bipo-
lar inputs. The internal-reference voltage is adjustable
to ±1.5% with the circuit of Figure 15.
1
10
100
0.01
0.1
1
10
100
1k
CONVERSION RATE (Hz)
AVERAGE
SUPPLY
CURRENT
(
A)
1 CHANNEL
RLOAD = ∞
CODE = 1010101000
4 CHANNELS
Figure 13a. MAX1248 Supply Current vs. Conversion Rate,
FULLPD
1
10
100
10,000
1000
0.1
10
1
100
1k
10k
100k
1M
CONVERSION RATE (Hz)
AVERAGE
SUPPLY
CURRENT
(
A)
RLOAD = ∞
CODE = 1010101000
4 CHANNELS
1 CHANNEL
3.0
2.5
2.0
1.5
1.0
0.5
0
0.01
0.1
1
10
TIME IN SHUTDOWN (sec)
POWER-UP
DELAY
(ms)
Figure 13b. MAX1248 Supply Current vs. Conversion Rate,
FASTPD
Figure 13c. Typical Reference-Buffer Power-Up Delay vs. Time
in Shutdown
______________________________________________________________________________________
17
相关PDF资料
MAX1279AETC+ IC ADC 12BIT 1.5MSPS 12-TQFN
MAX1285BESA+T IC ADC 12BIT 300KSPS 8-SOIC
MAX1302BEUG+ IC ADC 16BIT SRL 115KSPS 24TSSOP
MAX1303BEUP+ IC ADC 16BIT MULT RANGE 20TSSOP
MAX1308ECM+T IC ADC 12BIT 8CH 4MSPS 48LQFP
MAX1320ECM+T IC ADC 14BIT 8CH 2MSPS 48LQFP
MAX132EWG+T IC ADC 18BIT SERIAL 24-SOIC
MAX135EPI+ IC ADC 15BIT PARALLEL 28-DIP
相关代理商/技术参数
MAX1249AMJE 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
MAX1249BCEE 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
MAX1249BCEE+ 功能描述:模数转换器 - ADC 10-Bit 4Ch 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
MAX1249BCEE+T 功能描述:模数转换器 - ADC 10-Bit 4Ch 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
MAX1249BCEE-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
MAX1249BCPE 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
MAX1249BCPE+ 功能描述:模数转换器 - ADC 10-Bit 4Ch 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
MAX1249BEEE 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