- 您现在的位置：买卖IC网 > PDF目录224187 > MAX147AEPP+ (MAXIM INTEGRATED PRODUCTS INC) +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs PDF资料下载
参数资料
| 型号： | MAX147AEPP+ |
| 厂商： | MAXIM INTEGRATED PRODUCTS INC |
| 元件分类： | ADC |
| 英文描述： | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
| 中文描述： | 8-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, SERIAL ACCESS, PDIP20 |
| 封装： | 0.300 INCH, PLASTIC, DIP-20 |
| 文件页数： | 8/28页 |
| 文件大小： | 746K |
| 代理商： | MAX147AEPP+ |
第1页第2页第3页第4页第5页第6页第7页当前第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页
MAX146/MAX147
+2.7V, Low-Power, 8-Channel,
Serial 12-Bit ADCs
16
______________________________________________________________________________________
Reference-Buffer Compensation
In addition to its shutdown function, SHDN selects inter-
nal or external compensation. The compensation
affects both power-up time and maximum conversion
speed. The100kHz minimum clock rate is limited by
droop on the sample-and-hold and is independent of
the compensation used.
Float SHDN to select external compensation. The
Typical Operating Circuit uses a 4.7F capacitor at
VREF. A 4.7F value ensures reference-buffer stability
and allows converter operation at the 2MHz full clock
speed. External compensation increases power-up
time (see the Choosing Power-Down Mode section and
Table 4).
Pull SHDN high to select internal compensation.
Internal compensation requires no external capacitor at
VREF and allows for the shortest power-up times. The
maximum clock rate is 2MHz in internal clock mode
and 400kHz in external clock mode.
Choosing Power-Down Mode
You can save power by placing the converter in a low-
current shutdown state between conversions. Select full
power-down mode or fast power-down mode via bits 1
and 0 of the DIN control byte with SHDN high or floating
(Tables 1 and 5). In both software power-down modes,
the serial interface remains operational, but the ADC
does not convert. Pull SHDN low at any time to shut
down the converter completely. SHDN overrides bits 1
and 0 of the control byte.
Full power-down mode turns off all chip functions that
draw quiescent current, reducing supply current to 2A
(typ). Fast power-down mode turns off all circuitry
except the bandgap reference. With fast power-down
mode, the supply current is 30A. Power-up time can be
shortened to 5s in internal compensation mode.
Table 4 shows how the choice of reference-buffer com-
pensation and power-down mode affects both power-up
delay and maximum sample rate. In external compensa-
tion mode, power-up time is 20ms with a 4.7F compen-
sation capacitor when the capacitor is initially fully
discharged. From fast power-down, start-up time can be
eliminated by using low-leakage capacitors that do not
discharge more than 1/2LSB while shut down. In power-
down, leakage currents at VREF cause droop on the ref-
erence bypass capacitor. Figures 12a and 12b show
the various power-down sequences in both external and
internal clock modes.
Software Power-Down
Software power-down is activated using bits PD1 and PD0
of the control byte. As shown in Table 5, PD1 and PD0
also specify the clock mode. When software shutdown is
asserted, the ADC operates in the last specified clock
mode until the conversion is complete. Then the ADC
powers down into a low quiescent-current state. In internal
clock mode, the interface remains active and conversion
results may be clocked out after the MAX146/MAX147
enter a software power-down.
The first logical 1 on DIN is interpreted as a start bit
and powers up the MAX146/MAX147. Following
the start bit, the data input word or control byte also
determines clock mode and power-down states. For
example, if the DIN word contains PD1 = 1, then the
chip remains powered up. If PD0 = PD1 = 0, a
power-down resumes after one conversion.
Table 4. Typical Power-Up Delay Times
133
2
Full
—
Disabled
133
2
Fast
—
Disabled
133
See Figure 14c
Full
4.7
External
Enabled
133
See Figure 14c
Fast
4.7
External
Enabled
26
300
Full
—
Internal
Enabled
26
5
Fast
—
Internal
Enabled
MAXIMUM
SAMPLING RATE
(ksps)
POWER-UP
DELAY
(s)
POWER-DOWN
MODE
VREF
CAPACITOR
(F)
REFERENCE-
BUFFER
COMPENSATION
MODE
REFERENCE
BUFFER
相关PDF资料 |
PDF描述 |
|---|---|
| MAX147BCAP+ | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
| MAX147AEAP+T | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
| MAX147ACPP+ | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
| MAX147AEAP+ | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
| MAX147ACAP+T | +2.7V, Low-Power, 8-Channel, Serial 12-Bit ADCs |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX147AEPP+ | 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 |
| MAX147AMJP | 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 |
| MAX147BC/D | 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 |
| MAX147BCAP | 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 |
| MAX147BCAP+ | 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 |
发布紧急采购，3分钟左右您将得到回复。