- 您現在的位置：買賣IC網 > PDF目錄373919 > AD7849AN (ANALOG DEVICES INC) Serial Input, 14-Bit/16-Bit DAC PDF資料下載
參數資料
| 型號： | AD7849AN |
| 廠商： | ANALOG DEVICES INC |
| 元件分類： | DAC |
| 英文描述： | Serial Input, 14-Bit/16-Bit DAC |
| 中文描述： | SERIAL INPUT LOADING, 7 us SETTLING TIME, 14-BIT DAC, PDIP20 |
| 封裝： | PLASTIC, DIP-20 |
| 文件頁數： | 10/15頁 |
| 文件大小： | 211K |
| 代理商： | AD7849AN |
REV. B
–
10
–
AD7849
t
2
t
4
t
5
t
1
t
3
DB0 (N)
DB15
(N+1)
t
5
t
4
DB0
(N+1)
DB0 (N)
DB15 (N)
DB0 (N)
DB13 (N)
DB13
(N+1)
DB0
(N+1)
DB0 (N)
DB13 (N)
t
6
SCLK
SYNC
BIN
/COMP
SDIN
(AD7849B/C/T)
SDOUT
(AD7849B/C/T)
SDIN
(AD7849A)
SDOUT
(AD7849A)
LDAC
,
CLR
DCEN IS TIED PERMANENTLY HIGH
t
7
DB15 (N)
t
6
Figure 14. Timing Diagram (Daisy-Chain Mode)
Serial Data Loading Format (Daisy Chain Mode)
By connecting DCEN high, the daisy-chain mode is enabled.
This mode of operation is designed for multi-DAC systems
where several AD7849s may be connected in cascade. In this
mode, the internal gating circuitry on SCLK is disabled and a
serial data output facility is enabled. The internal gating signal
is permanently active (low) so that the SCLK signal is continu-
ously applied to the input shift register when
SYNC
is low. The
data is clocked into the register on each falling SCLK edge after
SYNC
going low. If more than 16 clock pulses are applied, the
data ripples out of the shift register and appears on the
SDOUT line. By connecting this line to the SDIN input on the
next AD7849 in the chain, a multi-DAC interface may be con-
structed. Sixteen SCLK pulses are required for each DAC in the
system. Therefore the total number of clock cycles must equal
16
×
N where N is the total number of devices in the chain.
When the serial transfer to all devices is complete,
SYNC
is
taken high. This prevents any further data being clocked into
the input register.
A continuous SCLK source may be used if it can be arranged
that
SYNC
is held low for the correct number of clock cycles.
Alternatively, a burst clock containing the exact number of clock
cycles may be used and
SYNC
taken high some time later.
When the transfer to all input registers is complete, a common
LDAC
signal updates all DAC latches with the data in each in-
put register. All analog outputs are therefore updated simulta-
neously, 5
μ
s after the falling edge of
LDAC
.
Clear Function (
CLR
)
The clear function bypasses the input shift register and loads the
DAC Latch with all 0s. It is activated by taking
CLR
low. In all
ranges except the Offset Binary bipolar range (–5 V to +5 V) the
output voltage is reset to 0 V. In the offset binary bipolar range
the output is set to V
REF–
. This clear function is distinct and
separate from the automatic power-on reset feature of the device.
APPLYING THE AD7849
Power Supply Sequencing and Decoupling
In the AD7849, V
CC
should not exceed V
DD
by more than
0.4 V. If this does happen then an internal diode can be turned
on and produce latch-up in the device. Care should be taken to
employ the following power supply sequence: V
DD
; V
SS
; V
CC
.
In systems where it is possible to have an incorrect power
sequence (for example, if V
CC
is greater than 0.4 V while V
DD
is
still 0 V), the circuit of Figure 15 may be used to ensure that
the Absolute Maximum Ratings are not exceeded.
SD103C
1N5711
1N5712
1N4148
V
DD
V
CC
V
DD
V
CC
AD7849
Figure 15. Power Supply Protection
相關PDF資料 |
PDF描述 |
|---|---|
| AD7849AR | Serial Input, 14-Bit/16-Bit DAC |
| AD7849BN | Serial Input, 14-Bit/16-Bit DAC |
| AD7849BR | Serial Input, 14-Bit/16-Bit DAC |
| AD7849CN | Serial Input, 14-Bit/16-Bit DAC |
| AD7849CR | Serial Input, 14-Bit/16-Bit DAC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD7849ANZ | 功能描述:IC DAC 16BIT SERIAL INP 20DIP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 數模轉換器 系列:- 產品培訓模塊:Data Converter Fundamentals DAC Architectures 標準包裝:750 系列:- 設置時間:7µs 位數:16 數據接口:并聯 轉換器數目:1 電壓電源:雙 ± 功率耗散（最大）:100mW 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-LCC（J 形引線） 供應商設備封裝:28-PLCC（11.51x11.51） 包裝:帶卷 (TR) 輸出數目和類型:1 電壓，單極；1 電壓，雙極 采樣率（每秒）:143k |
| AD7849AR | 功能描述:IC DAC 16BIT SRL INP 20-SOIC RoHS:否 類別:集成電路 (IC) >> 數據采集 - 數模轉換器 系列:- 產品培訓模塊:Data Converter Fundamentals DAC Architectures 標準包裝:750 系列:- 設置時間:7µs 位數:16 數據接口:并聯 轉換器數目:1 電壓電源:雙 ± 功率耗散（最大）:100mW 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-LCC（J 形引線） 供應商設備封裝:28-PLCC（11.51x11.51） 包裝:帶卷 (TR) 輸出數目和類型:1 電壓，單極；1 電壓，雙極 采樣率（每秒）:143k |
| AD7849AR-REEL | 功能描述:IC DAC 16BIT SRL INP 20-SOIC RoHS:否 類別:集成電路 (IC) >> 數據采集 - 數模轉換器 系列:- 標準包裝:2,400 系列:- 設置時間:- 位數:18 數據接口:串行 轉換器數目:3 電壓電源:模擬和數字 功率耗散（最大）:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:36-TFBGA 供應商設備封裝:36-TFBGA 包裝:帶卷 (TR) 輸出數目和類型:* 采樣率（每秒）:* |
| AD7849ARZ | 功能描述:IC DAC 14/16BIT SRL-IN 20-SOIC RoHS:是 類別:集成電路 (IC) >> 數據采集 - 數模轉換器 系列:- 標準包裝:1 系列:- 設置時間:4.5µs 位數:12 數據接口:串行，SPI? 轉換器數目:1 電壓電源:單電源 功率耗散（最大）:- 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 供應商設備封裝:8-SOICN 包裝:剪切帶 (CT) 輸出數目和類型:1 電壓，單極；1 電壓，雙極 采樣率（每秒）:* 其它名稱:MCP4921T-E/SNCTMCP4921T-E/SNRCTMCP4921T-E/SNRCT-ND |
| AD7849ARZ-REEL | 功能描述:IC DAC 14/16BIT SRL-IN 20-SOIC RoHS:是 類別:集成電路 (IC) >> 數據采集 - 數模轉換器 系列:- 標準包裝:47 系列:- 設置時間:2µs 位數:14 數據接口:并聯 轉換器數目:1 電壓電源:單電源 功率耗散（最大）:55µW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:28-SSOP（0.209"，5.30mm 寬） 供應商設備封裝:28-SSOP 包裝:管件 輸出數目和類型:1 電流，單極；1 電流，雙極 采樣率（每秒）:* |
發布緊急采購，3分鐘左右您將得到回復。