参数资料
| 型号： | LT3028EDHC#PBF |
| 厂商： | Linear Technology |
| 文件页数： | 11/16页 |
| 文件大小： | 0K |
| 描述： | IC REG LDO ADJ .5A/.1A 16-DFN |
| 产品培训模块： | More Information on LDOs |
| 标准包装： | 73 |
| 稳压器拓扑结构： | 正，可调式 |
| 输出电压： | 1.22 V ~ 20 V |
| 输入电压： | 1.8 V ~ 20 V |
| 电压 - 压降（标准）： | 0.32V @ 500mA，0.3V @ 100mA |
| 稳压器数量： | 2 |
| 电流 - 输出： | 500mA，100mA |
| 电流 - 限制（最小）： | 520mA，110mA |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-WFDFN 裸露焊盘 |
| 供应商设备封装： | 16-DFN（5x3） |
| 包装： | 管件 |
| 产品目录页面： | 1330 (CN2011-ZH PDF) |
LT3028
APPLICATIO S I FOR ATIO
than 1 μ A in shutdown. In addition to the low quiescent
current, the LT3028 regulator incorporates several pro-
tection features which make it ideal for use in battery-
powered systems. The device is protected against reverse
input voltages. Additionally, in dual supply applications
where the regulator load is returned to a negative supply,
the output can be pulled below ground by as much as 20V
and still allow the device to start and operate.
Adjustable Operation
The LT3028 has an output voltage range of 1.22V to 20V.
The output voltage is set by the ratio of two external resis-
tors as shown in Figure 1. The device servos the output to
maintain the corresponding ADJ pin voltage at 1.22V ref-
erenced to ground. The current in R1 is then equal to
1.22V/R1 and the current in R2 is the current in R1 plus the
ADJ pin bias current. The ADJ pin bias current, 30nA at
25 ° C, flows through R2 into the ADJ pin. The output volt-
age can be calculated using the formula in Figure 1. The
value of R1 should be no greater than 250k to minimize
errors in the output voltage caused by the ADJ pin bias
current. Note that in shutdown the output is turned off and
the divider current will be zero. Curves of ADJ Pin Voltage
vs Temperature and ADJ Pin Bias Current vs Temperature
appear in the Typical Performance Characteristics.
The device is tested and specified with the ADJ pin tied to
the corresponding OUT pin for an output voltage of 1.22V.
Specifications for output voltages greater than 1.22V will
be proportional to the ratio of the desired output voltage
to 1.22V: V OUT /1.22V. For example, load regulation on
Output 2 for an output current change of 1mA to 100mA
is –1mV typical at V OUT = 1.22V. At V OUT = 12V, load
regulation is:
(12V/1.22V)(–1mV) = – 9.8mV
Bypass Capacitance and Low Noise Performance
The LT3028 regulator may be used with the addition of a
bypass capacitor from V OUT to the corresponding BYP pin
to lower output voltage noise. A good quality low leakage
capacitor is recommended. This capacitor will bypass the
reference of the regulator, providing a low frequency noise
pole. The noise pole provided by this bypass capacitor will
lower the output voltage noise to as low as 20 μ V RMS with
the addition of a 0.01 μ F bypass capacitor. Using a bypass
capacitor has the added benefit of improving transient
response. With no bypass capacitor and a 10 μ F output
capacitor, a 10mA to 100mA load step on Output 2 will
settle to within 1% of its final value in less than 100 μ s. With
the addition of a 0.01 μ F bypass capacitor, the output will
stay within 1% for the same load step. Both outputs exhibit
this improvement in transient response (see Transient
Reponse in Typical Performance Characteristics section).
However, regulator start-up time is inversely proportional
to the size of the bypass capacitor, slowing to 15ms with
a 0.01 μ F bypass capacitor and 10 μ F output capacitor.
Output Capacitance and Transient Response
The LT3028 regulator is designed to be stable with a wide
range of output capacitors. The ESR of the output capaci-
tor affects stability, most notably with small capacitors.
A minimum output capacitor of 1 μ F with an ESR of 3 ? or
less is recommended for Output 2 to prevent oscillations.
A minimum output capacitor of 3.3 μ F with an ESR of 3 ?
OUT1/OUT2
V OUT
or less is recommended for Output 1. The LT3028 is a
V OUT ADJ )( R 2 )
? + ( I
= 1 . 22 V ? 1 +
V IN
IN1/IN2
LT3028
ADJ1/ADJ2
GND
+
R1
R2
? R2 ?
? R 1 ?
V ADJ = 1 . 22 V
I ADJ = 30 nA AT 25 ° C
OUTPUT RANGE = 1 . 22 V TO 20 V
micropower device and output transient response will be
a function of output capacitance. Larger values of output
capacitance decrease the peak deviations and provide
improved transient response for larger load current
3024 F01
Figure 1. Adjustable Operation
changes. Bypass capacitors, used to decouple individual
components powered by the LT3028, will increase the
effective output capacitor value. With larger capacitors
3028f
11
相关PDF资料 |
PDF描述 |
|---|---|
| ISL8101IRZ-T | IC PWM CTRLR BUCK 2PHASE 24-QFN |
| MIC39501-2.5WU | IC REG LDO 2.5V 5A TO-263-5 |
| ISL6324CRZ-T | IC HYBRID CTRLR PWM DUAL 48-QFN |
| LT1963AEFE-3.3#PBF | IC REG LDO 3.3V 1.5A 16TSSOP |
| HIP6004DCRZ-T | IC CTRLR PWM VOLTAGE MON 20-QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3028EFE | 制造商:Linear Technology 功能描述:LDO Regulator Pos 1.22V to 20V 0.1A/0.5A 16-Pin TSSOP EP |
| LT3028EFE#PBF | 功能描述:IC REG LDO ADJ .5A/.1A 16-TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 系列:- 标准包装:1 系列:- 稳压器拓扑结构:正，固定式 输出电压:8V 输入电压:10.5 V ~ 23 V 电压 - 压降（标准）:1.7V @ 40mA 稳压器数量:1 电流 - 输出:100mA（最小值） 电流 - 限制（最小）:- 工作温度:0°C ~ 125°C 安装类型:表面贴装 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 供应商设备封装:8-SOIC 包装:剪切带 (CT) 产品目录页面:1075 (CN2011-ZH PDF) 其它名称:296-24390-1 |
| LT3028EFE#TRPBF | 功能描述:IC REG LDO ADJ .5A/.1A 16-TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 系列:- 标准包装:800 系列:- 稳压器拓扑结构:正，固定式 输出电压:2.5V 输入电压:最高 16V 电压 - 压降（标准）:0.7V @ 4A 稳压器数量:1 电流 - 输出:4A 电流 - 限制（最小）:4.2A 工作温度:0°C ~ 125°C 安装类型:表面贴装 封装/外壳:TO-263-6，D²Pak（5 引线+接片），TO-263BA 供应商设备封装:TO-263-5 包装:带卷 (TR) 其它名称:AP1184K525L-13AP1184K525LDITR |
| LT3028EFEPBF | 制造商:Linear Technology 功能描述:LT3028 dual adj 500/100mA LDO regulator |
| LT3028IDHC | 制造商:Linear Technology 功能描述:LDO Regulator Pos 1.22V to 20V1.22V to 20V 0.1A/0.5A 16-Pin DFN EP |
发布紧急采购，3分钟左右您将得到回复。