- 您現在的位置：買賣IC網 > PDF目錄373923 > AD7888 (Analog Devices, Inc.) +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP PDF資料下載
參數資料
| 型號： | AD7888 |
| 廠商： | Analog Devices, Inc. |
| 英文描述： | +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP |
| 中文描述： | 2.7 V至5.25 V，微功耗，8通道，125 kSPS的，12位ADC的16引腳TSSOP |
| 文件頁數： | 11/16頁 |
| 文件大小： | 164K |
| 代理商： | AD7888 |
REV. 0
AD7888
–11–
MODES OF OPERATION
The AD7888 has a number of different modes of operation.
These are designed to provide flexible power management
options. These options can be chosen to optimize the power
dissipation/throughput rate ratio for differing application re-
quirements. The modes of operation are controlled by the PM1
and PM0 bits of the Control Register as outlined previously.
Normal Mode (PM1 = 0, PM0 = 0)
This mode is intended for fastest throughput rate performance
as the user does not have to worry about any power-up times
with the AD7888 remaining fully powered all the time. Figure
13 shows the general diagram of the operation of the AD7888 in
this mode.
The data presented to the AD7888 on the DIN line during the
first eight clock cycles of the data transfer are loaded to the
Control Register. The part will remain powered up at the end of
the conversion as long as PM1 and PM0 were set to zero in the
write during that conversion. To continue to operate in this
mode, the user must ensure that PM1 and PM0 are both loaded
with 0 on every data transfer.
The falling edge of
CS
initiates the sequence and the input
signal is sampled on the second rising edge of the SCLK input.
Sixteen serial clock cycles are required to complete the conver-
sion and access the conversion result. Once a data transfer is
complete (
CS
has returned high), another conversion can be
initiated immediately by bringing
CS
low again.
Full Shutdown (PM1 = 0, PM0 = 1)
In this mode, all internal circuitry on the AD7888, including the
on-chip reference, is powered-down. The part retains the infor-
mation in the Control Register during full shutdown. The part
remains in full shutdown until the power management bits are
changed. If the power management bits are changed to PM1 = 1
and PM0 = 0, i.e., the autoshutdown mode, the part will remain
in shutdown (now in autoshutdown) but will power up once a
conversion is initiated after that (see Power-Up Times section).
The part changes mode as soon as the control register has been
updated, so if the part is in full shutdown mode and the power
management bits are changed to PM1 = PM0 = 0, i.e., normal
mode, then the part will power up on the 16th SCLK rising edge.
Autoshutdown (PM1 = 1, PM0 = 0)
In this mode, the AD7888 automatically enters its power-down
mode at the end of every conversion. Figure 14a shows the
general diagram of the operation of the AD7888 in this mode.
When
CS
goes from high to low, all on-chip circuitry will start
to power up on the next falling edge of SCLK. On the sixteenth
SCLK rising edge the part will power down again. It takes ap-
proximately 5
μ
s for the AD7888 internal circuitry to be fully
powered up. As a result, a conversion (or sample-and-hold
acquisition) should not be initiated during this 5
μ
s. The input
signal is sampled on the second rising edge of SCLK following
the
CS
falling edge. The user should ensure that 5
μ
s elapse
between the first falling edge of SCLK after the falling edge of
SCLK
4 LEADING ZEROES + CONVERSION RESULT
CS
DOUT
DATA IN
DIN
THE PART REMAINS POWERED UP
AT ALL TIMES AS PM1 AND PM0 = 0
1
16
CONTROL REGISTER DATA IS LOADED ON THE
FIRST 8 CLOCKS. PM1 AND PM0 = 0 TO KEEP
THE PART IN THIS MODE
Figure 13. Normal-Mode Operation
SCLK
4 LEADING ZEROES + CONVERSION RESULT
CS
DOUT
DATA IN
DIN
THE PART POWERS UP FROM
SHUTDOWN ON SCLK FALLING EDGE AS
PM1 = 1 AND PM0 = 0
1
16
4 LEADING ZEROES + CONVERSION RESULT
DATA IN
1
16
2
t
10
= 5
m
s
THE PART ENTERS
SHUTDOWN AT THE END OF
CONVERSION AS PM1 = 1 AND PM0 = 0
CONTROL REGISTER DATA IS LOADED ON THE
FIRST 8 CLOCKS. PM1 = 1 AND PM0 = 0
PM1 = 1 AND PM0 = 0 TO KEEP THE
PART IN THIS MODE
Figure 14a. Autoshutdown Operation
相關PDF資料 |
PDF描述 |
|---|---|
| AD7888AR | +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP |
| AD7888ARU | +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP |
| AD7888BR | +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP |
| AD7888BRU | +2.7 V to +5.25 V, Micropower, 8-Channel, 125 kSPS, 12-Bit ADC in 16-Lead TSSOP |
| AD7889 | 12-Bit 600 kSPS ADC(單電源600kSPS12位A/D轉換器) |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD7888AR | 制造商:Analog Devices 功能描述:ADC Single SAR 125ksps 12-bit Serial 16-Pin SOIC N 制造商:Analog Devices 功能描述:IC 12BIT ADC 8CH MICROPOWER 7888 |
| AD7888AR-REEL | 制造商:Analog Devices 功能描述:ADC Single SAR 125ksps 12-bit Serial 16-Pin SOIC N T/R |
| AD7888AR-REEL7 | 制造商:Analog Devices 功能描述:ADC Single SAR 125ksps 12-bit Serial 16-Pin SOIC N T/R |
| AD7888ARU | 功能描述:IC ADC 12BIT 8CH 125KSPS 16TSSOP RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:12 采樣率（每秒）:300k 數據接口:并聯 轉換器數目:1 功率耗散（最大）:75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC（0.295"，7.50mm 寬） 供應商設備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數目和類型:1 個單端，單極；1 個單端，雙極 |
| AD7888ARU-REEL | 功能描述:IC ADC 12BIT 8CH SRL 16-TSSOP RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:16 采樣率（每秒）:45k 數據接口:串行 轉換器數目:2 功率耗散（最大）:315mW 電壓電源:模擬和數字 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-SOIC（0.295"，7.50mm 寬） 供應商設備封裝:28-SOIC W 包裝:帶卷 (TR) 輸入數目和類型:2 個單端，單極 |
發布緊急采購，3分鐘左右您將得到回復。