- 您現在的位置：買賣IC網 > PDF目錄10148 > LTC1749CFW (Linear Technology)IC ADC 12BIT 80MSPS SMPL 48TSSOP PDF資料下載
參數資料
| 型號： | LTC1749CFW |
| 廠商： | Linear Technology |
| 文件頁數： | 6/20頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC ADC 12BIT 80MSPS SMPL 48TSSOP |
| 標準包裝： | 39 |
| 位數： | 12 |
| 采樣率（每秒）： | 80M |
| 數據接口： | 并聯 |
| 轉換器數目： | 1 |
| 功率耗散（最大）： | 1.69W |
| 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： | 48-TFSOP（0.240"，6.10mm 寬） |
| 供應商設備封裝： | 48-TSSOP |
| 包裝： | 管件 |
| 輸入數目和類型： | 2 個單端，雙極；1 個差分，雙極 |
14
LTC1749
1749f
can be configured in a noise gain of +2 with the addition of
two equal valued resistors between the output and invert-
ing input and between the two inputs. This however will raise
the noise contributed by the op amps.
Reference Operation
Figure 5 shows the LTC1749 equivalent reference circuitry
consisting of a 2V bandgap reference, a 3-to-1 switch, a
switch control circuit and a difference amplifier.
The 2V bandgap reference serves two functions. First, it is
assessable at the VCM pin to provide a DC bias point for
setting the common mode voltage of any external input
circuitry. Second, it is used to derive internal reference
levels that may be used to set the input range of the ADC.
An external bypass capacitor is required for the 2V refer-
ence output at the VCM pin. This provides a high frequency
low impedance path to ground for internal and external
circuitry. This is also the compensation capacitor for the
reference, which will not be stable without this capacitor.
To achieve the optimal input range for an application, the
internal reference voltage (VREF) is flexible. The reference
switch shown in Figure 5 connects VREF to one of two
internally derived reference voltages, or to an externally
derived reference voltage. The internally derived refer-
ences are selected by strapping the SENSE pin to GND for
0.7V, or to VDD for 1.125V. When 0.7V > VSENSE > 1.125V,
VSENSE is directly connected to VREF. Because of the dual
nature of the SENSE pin, driving it with a logic device is not
recommended.
Reference voltages between 0.7V and 1.125V may be
programmed with two external resistors as shown in
Figure 6a. An external reference may be used by applying
its output directly or through a resistor divider to the
SENSE pin (Figure 6b). When the SENSE pin is driven with
an externally derived reference voltage, it should be by-
passed to ground as close to the device as possible with
a 1
F ceramic capacitor.
A difference amplifier generates the high and low refer-
ences for the ADC. High speed switching circuits are
connected to these outputs and they must be externally
bypassed. Each output has two pins: REFHA and REFHB
for the high reference and REFLA and REFLB for the low
reference. The doubled output pins are needed to reduce
package inductance. Bypass capacitors must be con-
nected as shown in Figure 5.
APPLICATIO S I FOR ATIO
WU
UU
VCM
REFHA
REFLB
SENSE
TIE TO VDD FOR VREF = 1.125;
TIE TO GND FOR VREF = 0.7V;
VREF = VSENSE FOR
0.7V < VSENSE < 1.125V
2V
REFLA
REFHB
4.7
F
4.7
F
INTERNAL ADC
HIGH REFERENCE
BUFFER
VREF
0.1
F
1749 F05
LTC1749
4
DIFF AMP
1
F
1
F
0.1
F
INTERNAL ADC
LOW REFERENCE
2V BANDGAP
REFERENCE
1.125V 0.7V
RANGE
DETECT
AND
CONTROL
Figure 5. Equivalent Reference Circuit
Figure 4. Differential Drive with Op Amps
25
5V
SINGLE-ENDED
INPUT
2V
±1/2
RANGE
VCM
AIN
+
AIN
–
12pF
1749 F04
4.7
F
25
100
500
500
25
25
LTC1749
–
+
1/2 LT1818
–
+
1/2 LT1818
相關PDF資料 |
PDF描述 |
|---|---|
| VI-B5Z-MX | CONVERTER MOD DC/DC 2V 30W |
| EN3P15F26X | CONN RCPT 15POS FEMALE PANEL #26 |
| MS27473E16B99PD | CONN PLUG 23POS STRAIGHT W/PINS |
| IDT7201LA25J8 | IC MEM FIFO 512X9 25NS 32-PLCC |
| IDT7200L50SO8 | IC MEM FIFO 256X9 50NS 28-SOIC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| LTC1749CFW#PBF | 功能描述:IC ADC 12BIT 80MSPS SMPL 48TSSOP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 位數:12 采樣率（每秒）:3M 數據接口:- 轉換器數目:- 功率耗散（最大）:- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數目和類型:- |
| LTC1749CFW#TR | 功能描述:IC ADC 12BIT 80MSPS SMPL 48TSSOP 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 系列:- 位數:14 采樣率（每秒）:83k 數據接口:串行，并聯 轉換器數目:1 功率耗散（最大）:95mW 電壓電源:雙 ± 工作溫度:0°C ~ 70°C 安裝類型:通孔 封裝/外殼:28-DIP（0.600"，15.24mm） 供應商設備封裝:28-PDIP 包裝:管件 輸入數目和類型:1 個單端，雙極 |
| LTC1749CFW#TRPBF | 功能描述:IC ADC 12BIT 80MSPS SMPL 48TSSOP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 位數:12 采樣率（每秒）:3M 數據接口:- 轉換器數目:- 功率耗散（最大）:- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數目和類型:- |
| LTC1749IFW | 功能描述:IC ADC 12BIT 80MSPS SMPL 48TSSOP 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 系列:- 位數:14 采樣率（每秒）:83k 數據接口:串行，并聯 轉換器數目:1 功率耗散（最大）:95mW 電壓電源:雙 ± 工作溫度:0°C ~ 70°C 安裝類型:通孔 封裝/外殼:28-DIP（0.600"，15.24mm） 供應商設備封裝:28-PDIP 包裝:管件 輸入數目和類型:1 個單端，雙極 |
| LTC1749IFW#PBF | 功能描述:IC ADC 12BIT 80MSPS SMPL 48TSSOP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 位數:12 采樣率（每秒）:3M 數據接口:- 轉換器數目:- 功率耗散（最大）:- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數目和類型:- |
發(fā)布緊急采購，3分鐘左右您將得到回復。