收藏本站

AD580
THEORY OF OPERATION
The AD580 family (AD580, AD581, AD584, AD589) uses the
+V IN
R8
R7
bandgap concept to produce a stable, low temperature coef-
ficient voltage reference suitable for high accuracy data acqui-
I 2 ? I 1
V OUT = V Z 1 +
R 4
R 5
= 2.5V
sition components and systems. The device makes use of the
underlying physical nature of a silicon transistor base-emitter
Q2
8A
Q1
A
R4
V Z = V BE + V 1
voltage in the forward-biased operating region. All such tran-
? V BE
R2
V BE (Q1)
R5
= V BE + 2
R 1
R 2
? V BE
ln 1
sistors have approximately a –2 mV/°C temperature coefficient,
unsuitable for use directly as a low TC reference. Extrapolation
of the temperature characteristic of any one of these devices to
2I 1 = I 1 + I 2
COM
R1
V 1 = 2
R 1
R 2
? V BE
= V BE + 2
= 1.205V
R 1 kT
R 2 q
J
J 2
absolute zero (with an emitter current propor-tional to the
absolute temperature), however, reveals that it will go to a V BE of
1.205 V at 0 K, as shown in Figure 3. Thus, if a voltage could be
Figure 4. Basic Bandgap-Reference Regulator Circuit
+E
developed with an opposing temperature coefficient to sum
with V BE to total 1.205 V, a 0 TC reference would result and
operation from a single, low voltage supply would be possible.
The AD580 circuit provides such a compensating voltage, V1 in
Q14
R12
R13
Q13
Q4
Figure 4, by driving two transistors at different current densities
and amplifying the resulting V BE difference (?V BE —which now
R8
R7
Q3
R6
Q7
has a positive TC). The sum, V Z , is then buffered and amplified
up to 2.5 V to provide a usable reference-voltage output. Figure
Q10
Q11
Q12
Q6
5 shows the schematic diagram of the AD580.
The AD580 operates as a 3-terminal reference, meaning that no
Q8
Q2
R3
Q9
Q1
Q15
C1
Q5
R10
R9
R4
2.5V
OUT
additional components are required for biasing or current
8A
A
setting. The connection diagram, Figure 6, is quite simple.
R2
R11
R5
R1
1.5
CONSTANT SUM = 1.205V
COM
–E
Figure 5. Schematic Diagram
1.205
1.0
FOR BOTH
DEVICES
4.5 ≤ V IN ≤ 30V
AD580
+E
E OUT
0.5
V BE VS. TEMPERATURE
FOR TWO TYPICAL
DEVICES (I E α T)
–E
LOAD
REQUIRED
COMPENSATION
Figure 6. Connection Diagram
0
–273 ° C
0K
–200 ° C
73K
–100 ° C
173K
VOLTAGE–
SAME DEVICES
0 ° C
273K
100 ° C
373K
VOLTAGE VARIATION VERSUS TEMPERATURE
Some confusion exists in the area of defining and specifying
TEMPERATURE
Figure 3. Extrapolated Variation of Base-Emitter Voltage with Temperature
(I E αT), and Required Compensation, Shown for Two Different Devices
reference voltage error over temperature. Historically, references
are characterized using a maximum deviation per degree
Centigrade; i.e., 10 ppm/°C. However, because of the
inconsistent nonlinearities in Zener references (butterfly or S
type characteristics), most manufacturers use a maximum limit
error band approach to characterize their references. This
technique measures the output voltage at 3 to 5 different
temperatures and guarantees that the output voltage deviation
will fall within the guaranteed error band at these discrete
temperatures. This approach, of course, makes no mention or
guarantee of performance at any other temperature within the
operating temperature range of the device.
Rev. B | Page 5 of 8
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
LQW2UASR33J00L IND 330NH 450MA SRF 570MHZ 1008
MIC2549A-1BTS IC SW CURR LIMIT HI SIDE 14TSSOP
F931C107MNC CAP TANT 100UF 16V 20% 2917
592D106X9010B8T15H CAP TANT 10UF 10V 10% 1611
GEM28DTAH-S189 CONN EDGECARD 56POS R/A .156 SLD
ASPI-0615FS-4R7M-T2 INDUCTOR SHLD POWER 4.7UH SMD
ADR431BRMZ IC VREF SERIES PREC 2.5V 8MSOP
GEM28DTAD-S189 CONN EDGECARD 56POS R/A .156 SLD
相关代理商/技术参数
AD580L 制造商:AD 制造商全称:Analog Devices 功能描述:High Precision 2.5 V IC Reference
AD580LCSA 制造商:未知厂家 制造商全称:未知厂家 功能描述:Voltage Reference
AD580LH 功能描述:IC VREF SERIES PREC 2.5V TO-52-3 RoHS:是 类别:集成电路 (IC) >> PMIC - 电压基准 系列:- 标准包装:3,000 系列:- 基准类型:旁路，精度 输出电压:3V 容差:±0.5% 温度系数:100ppm/°C 输入电压:- 通道数:1 电流 - 阴极:82µA 电流 - 静态:- 电流 - 输出:15mA 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:6-TSSOP（5 引线），SC-88A，SOT-353 供应商设备封装:SC-70-5 包装:带卷 (TR) 其它名称:296-20888-2
AD580LMH 制造商:AD 制造商全称:Analog Devices 功能描述:High Precision,2.5 V IC Reference
AD580M 制造商:AD 制造商全称:Analog Devices 功能描述:High Precision 2.5 V IC Reference
AD580MCSA 制造商:未知厂家 制造商全称:未知厂家 功能描述:Voltage Reference
AD580MH 制造商:Analog Devices 功能描述:
AD580S 制造商:AD 制造商全称:Analog Devices 功能描述:High Precision 2.5 V IC Reference