参数资料
型号: MAX1249AEPE+
厂商: Maxim Integrated Products
文件页数: 10/24页
文件大小: 0K
描述: IC ADC 10BIT SERIAL 16-DIP
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 25
位数: 10
采样率(每秒): 133k
数据接口: MICROWIRE?,QSPI?,串行,SPI?
转换器数目: 1
功率耗散(最大): 842mW
电压电源: 单电源
工作温度: -40°C ~ 85°C
安装类型: 通孔
封装/外壳: 16-DIP(0.300",7.62mm)
供应商设备封装: 16-PDIP
包装: 管件
输入数目和类型: 4 个单端,单极;4 个单端,双极;2 个差分,单极;2 个差分,双极
MAX1248/MAX1249
+2.7V to +5.25V, Low-Power, 4-Channel,
Serial 10-Bit ADCs in QSOP-16
External Reference
With both the MAX1248 and MAX1249, an external ref-
erence can be placed at either the input (REFADJ) or
the output (VREF) of the internal reference-buffer ampli-
fier. The REFADJ input impedance is typically 20k
for
the MAX1248 and higher than 100k
for the MAX1249,
where the internal reference is omitted. At VREF, the
DC input resistance is a minimum of 18k
. During con-
version, an external reference at VREF must deliver
up to 350A 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 4.7F capacitor.
Using the REFADJ input makes buffering the external
reference unnecessary. To use the direct VREF input,
disable the internal buffer by tying REFADJ to VDD. In
power-down, the input bias current to REFADJ can be
as much as 25A with REFADJ tied to VDD. Pull
REFADJ to AGND to minimize the input bias current in
power-down.
Transfer Function
Table 7 shows the full-scale voltage ranges for unipolar
and bipolar modes.
The external reference must have a temperature coeffi-
cient of 20ppm/°C or less to achieve accuracy to within
1LSB over the commercial temperature range of 0°C to
+70°C.
Figure 16 depicts the nominal, unipolar input/output
(I/O) transfer function, and Figure 17 shows the bipolar
input/output transfer function. Code transitions occur
halfway between successive-integer LSB values.
Output coding is binary, with 1LSB = 2.44mV (2.500V /
1024) for unipolar operation and 1LSB = 2.44mV
[(2.500V / 2 - -2.500V / 2) / 1024] for bipolar operation.
OUTPUT CODE
FULL-SCALE
TRANSITION
11 . . . 111
11 . . . 110
11 . . . 101
00 . . . 011
00 . . . 010
00 . . . 001
00 . . . 000
1
2
3
0
(COM)
FS
FS - 3/2LSB
FS = VREF + COM
ZS = COM
INPUT VOLTAGE (LSBs)
1LSB =
VREF
1024
Figure 16. Unipolar Transfer Function, Full Scale (FS) = VREF
+ COM, Zero Scale (ZS) = COM
+3.3V
510k
24k
100k
0.01F
9
REFADJ
MAX1248
Figure 15. MAX1248 Reference-Adjust Circuit
1
0 0
DIN
REFADJ
VREF
1.21V
0V
2.50V
0V
1
0 1
1
0 0
1
0 1
FULLPD
FASTPD
NOPD
FULLPD
FASTPD
1.6ms WAIT
COMPLETE CONVERSION SEQUENCE
tBUFFEN ≈ 75s
τ = RC = 20k x CREFADJ
(ZEROS)
CH1
CH7
(ZEROS)
Figure 14. MAX1248 FULLPD/FASTPD Power-Up Sequence
18
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参数描述
MAX1249AEPE+ 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
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