- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄2008 > MAX11643EEG+T (Maxim Integrated Products)IC ADC 8BIT 8CH 24QSOP PDF資料下載
參數(shù)資料
| 型號： | MAX11643EEG+T |
| 廠商： | Maxim Integrated Products |
| 文件頁數(shù)： | 5/22頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC ADC 8BIT 8CH 24QSOP |
| 產(chǎn)品培訓(xùn)模塊： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 標(biāo)準(zhǔn)包裝： | 2,500 |
| 位數(shù)： | 8 |
| 采樣率（每秒）： | 300k |
| 數(shù)據(jù)接口： | MICROWIRE?，QSPI?，串行，SPI? |
| 轉(zhuǎn)換器數(shù)目： | 1 |
| 功率耗散（最大）： | 762mW |
| 電壓電源： | 單電源 |
| 工作溫度： | -40°C ~ 85°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 24-SSOP（0.154"，3.90mm 寬） |
| 供應(yīng)商設(shè)備封裝： | 24-QSOP |
| 包裝： | 帶卷 (TR) |
| 輸入數(shù)目和類型： | 16 個(gè)單端，單極 |
MAX11638/MAX11639/MAX11642/MAX11643
8-Bit, 16-/8-Channel, 300ksps ADCs
with FIFO and Internal Reference
______________________________________________________________________________________
13
True Differential Analog Input T/H
The equivalent circuit of Figure 3 shows the
MAX11638/MAX11639/MAX11642/MAX11643’s input
architecture. In track mode, a positive input capacitor is
connected to AIN0–AIN15. A negative input capacitor is
connected to GND. For external T/H timing, use clock
mode 01. After the T/H enters hold mode, the difference
between the sampled positive and negative input volt-
ages is converted. The time required for the T/H to
acquire an input signal is determined by how quickly its
input capacitance is charged. If the input signal’s
source impedance is high, the required acquisition time
lengthens. The acquisition time, tACQ, is the maximum
time needed for a signal to be acquired, plus the power-
up time. It is calculated by the following equation:
tACQ = 9 x (RS + RIN) x 24pF + tPWR
where RIN = 1.5k, RS is the source impedance of the
input signal, and tPWR = 1s, the power-up time of the
device. The varying power-up times are detailed in the
explanation of the clock mode conversions. When the
conversion is internally timed, tACQ is never less than
1.4s, and any source impedance below 300
does not
significantly affect the ADC’s AC performance. A high-
impedance source can be accommodated either by
lengthening tACQ or by placing a 1F capacitor between
the positive and negative analog inputs.
Internal FIFO
The MAX11638/MAX11639/MAX11642/MAX11643 con-
tain a FIFO buffer that can hold up to 16 ADC results.
This allows the ADC to handle multiple internally clocked
conversions, without tying up the serial bus. If the FIFO is
filled and further conversions are requested without
reading from the FIFO, the oldest ADC results are over-
written by the new ADC results. Each result contains 2
bytes, with the MSB preceded by four leading zeros.
After each falling edge of CS, the oldest available byte of
data is available at DOUT, MSB first. When the FIFO is
empty, DOUT is zero.
Internal Clock
The MAX11638/MAX11639/MAX11642/MAX11643 oper-
ate from an internal oscillator, which is accurate within
10% of the 4.4MHz nominal clock rate. The internal
oscillator is active in clock modes 00, 01, and 10. Read
out the data at clock speeds up to 10MHz. See Figures
4–7 for details on timing specifications and starting a
conversion.
Applications Information
Register Descriptions
The MAX11638/MAX11639/MAX11642/MAX11643 com-
municate between the internal registers and the exter-
nal circuitry through the SPI-/QSPI-compatible serial
interface. Table 1 details the registers and the bit
names. Tables 2–5 show the various functions within
the conversion register, setup register, averaging regis-
ter, and reset register.
Conversion Time Calculations
The conversion time for each scan is based on a num-
ber of different factors: conversion time per sample,
samples per result, results per scan, and if the external
reference is in use.
Use the following formula to calculate the total conver-
sion time for an internally timed conversion in clock
modes 00 and 10 (see the
Electrical Characteristics
section as applicable):
Total Conversion Time = tCNV x nAVG x nRESULT + tRP
where:
tCNV = tACQ (max) + tCONV (max)
nAVG = samples per result (amount of averaging)
nRESULT = number of FIFO results requested;
determined by the number of channels being
scanned or by NSCAN1, NSCAN0
tRP = internal reference wake-up; set to zero if inter-
nal reference is already powered up or external ref-
erence is being used
In clock mode 01, the total conversion time depends on
how long CNVST is held low or high, including any time
required to turn on the internal reference. Conversion
time in externally clocked mode (CKSEL1, CKSEL0 = 11)
depends on the SCLK period and how long CS is held
high between each set of eight SCLK cycles. In clock
mode 01, the total conversion time does not include the
time required to turn on the internal reference.
REGISTER NAME
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Conversion
1
CHSEL3
CHSEL2
CHSEL1
CHSEL0
SCAN1
SCAN0
X
Setup
0
1
CKSEL1
CKSEL0
REFSEL1
REFSEL0
X
Averaging
0
1
AVGON
NAVG1
NAVG0
NSCAN1
NSCAN0
Reset
0001
RESET
XX
X
Table 1. Input Data Byte (MSB First)
X = Don’t care.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MAX11645EUA+T | IC ADC 12BIT I2C/SRL 1CH 8UMAX |
| MAX11647EUA+T | IC ADC 10BIT I2C 94.4KSPS 8UMAX |
| MAX1166BEUP+ | IC ADC 16BIT 165KSPS 20-TSSOP |
| MAX1168BCEG+ | IC ADC 16BIT 200KSPS 24-QSOP |
| MAX1183ECM+TD | IC ADC 10BIT 40MSPS DL 48-TQFP |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MAX11644 | 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:2.7V to 3.6V and 4.5V to 5.5V, Low-Power, 1-/2-Channel, 2-Wire Serial, 12-Bit ADCs |
| MAX11644EUA+ | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit 2Ch 94.4ksps 5.5V Precision ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
| MAX11644EUA+T | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit 2Ch 94.4ksps 5.5V Precision ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
| MAX11645EUA+ | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit 2Ch 94.4ksps 3.6V Precision ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
| MAX11645EUA+T | 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit 2Ch 94.4ksps 3.6V Precision ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-32 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。