参数资料
型号: ADP124ARHZ-3.0-R7
厂商: ANALOG DEVICES INC
元件分类: 固定正电压单路输出LDO稳压器
英文描述: 5.5V INPUT, 500 MA, LOW QUIESCENT CURRENT, CMOS LINEAR REGULATOR W/31 FIXED-OUTPUT VOLTAGES No of Pins: 8 Temperature Range: Ind
中文描述: 3 V FIXED POSITIVE LDO REGULATOR, 0.23 V DROPOUT, PDSO8
封装: ROHS COMPLIANT, MO-187AAT, MSOP-8
文件页数: 4/20页
文件大小: 648K
代理商: ADP124ARHZ-3.0-R7
ADP124/ADP125
Rev. A | Page 12 of 20
APPLICATIONS INFORMATION
CAPACITOR SELECTION
Output Capacitor
The ADP124/ADP125 are designed for operation with small,
space-saving ceramic capacitors, but these devices can function
with most commonly used capacitors as long as care is taken to
ensure an appropriate effective series resistance (ESR) value. The
ESR of the output capacitor affects the stability of the LDO control
loop. A minimum of 0.70 F capacitance with an ESR of 1 or
less is recommended to ensure stability of the ADP124/ADP125.
The transient response to changes in load current is also affected by
the output capacitance. Using a larger value of output capacitance
improves the transient response of the ADP124/ADP125 to
dynamic changes in load current. Figure 30 and Figure 31 show
the transient responses for output capacitance values of 1 F and
4.7 F, respectively.
08476-
028
M400ns
A CH1
200mA
1
2
T
13.20%
VIN = 4V
VOUT = 3.3V
VOUT
IOUT
1mA TO 500mA LOAD STEP
CH1 500mA
B
W
CH2 50.0mV
B
W
Figure 30. Output Transient Response, COUT = 1 F
08476-
029
M400ns
A CH1
200mA
1
2
T
13.60%
VIN = 4V
VOUT = 3.3V
VOUT
IOUT
1mA TO 500mA LOAD STEP
CH1 500mA
B
W
CH2 50.0mV
B
W
Figure 31. Output Transient Response, COUT = 4.7 F
Input Bypass Capacitor
Connecting a 1 F capacitor from VIN to GND reduces the circuit
sensitivity to the printed circuit board (PCB) layout, especially
when a long input trace or high source impedance is encountered.
If greater than 1 F of output capacitance is required, the input
capacitor should be increased to match it.
Input and Output Capacitor Properties
Any good quality ceramic capacitors can be used with the
ADP124/ADP125, as long as the capacitor meets the minimum
capacitance and maximum ESR requirements. Ceramic capacitors
are manufactured with a variety of dielectrics, each with different
behavior over temperature and applied voltage. Capacitors must
have an adequate dielectric to ensure the minimum capacitance
over the necessary temperature range and dc bias conditions.
Using an X5R or X7R dielectric with a voltage rating of 6.3 V or
10 V is recommended. However, using Y5V and Z5U dielectrics
are not recommended for any LDO, due to their poor temperature
and dc bias characteristics.
Figure 32 depicts the capacitance vs. capacitor voltage bias charac-
teristics of an 0402, 1 F, 10 V X5R capacitor. The voltage stability
of a capacitor is strongly influenced by the capacitor size and the
voltage rating. In general, a capacitor in a larger package or of a
higher voltage rating exhibits better stability. The temperature
variation of the X5R dielectric is about ±15% over the 40°C to
+85°C temperature range and is not a function of package or
voltage rating.
0.70
0.75
0.80
0.85
0.90
0.95
1.00
1.05
1.10
0
1
2
3
4
5
6
7
BIAS VOLTAGE (V)
CA
P
ACI
T
ANCE
(
F
)
08476-
030
Figure 32. Capacitance vs. Capacitor Voltage Bias Characteristics
Equation 1 can be used to determine the worst-case capacitance,
accounting for capacitor variation over temperature, component
tolerance, and voltage.
CEFF = C × (1 TEMPCO) × (1 TOL)
(1)
where:
CEFF is the effective capacitance at the operating voltage.
C is the rated capacitance value.
TEMPCO is the worst-case capacitor temperature coefficient.
TOL is the worst-case component tolerance.
相关PDF资料
PDF描述
ADP124ARHZ-3.3-R7 5.5V INPUT, 500 MA, LOW QUIESCENT CURRENT, CMOS LINEAR REGULATOR W/31 FIXED-OUTPUT VOLTAGES No of Pins: 8 Temperature Range: Ind
ADP125ARHZ 5.5V INPUT, 500 MA, LOW QUIESCENT CURRENT, CMOS LINEAR REGULATOR W/EXTERNAL VOLTAGE DIVIDER No of Pins: 8 Temperature Range: Ind
ADP125ARHZ-R7 5.5V INPUT, 500 MA, LOW QUIESCENT CURRENT, CMOS LINEAR REGULATOR W/EXTERNAL VOLTAGE DIVIDER No of Pins: 8 Temperature Range: Ind
ADP1875ARQZ-0.3-R7 SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PDSO16
ADP2121ACBZ-1.85R7 1.222 A SWITCHING REGULATOR, 6640 kHz SWITCHING FREQ-MAX, PBGA6
相关代理商/技术参数
参数描述
ADP124CP-3.3-EVALZ 制造商:AD 制造商全称:Analog Devices 功能描述:5.5 V Input, 500 mA, Low Quiescent Current, CMOS Linear Regulators
ADP124CPZ-REDYKIT 功能描述:REDYKIT 2.8/3.3 ADP124CPZ RoHS:是 类别:编程器,开发系统 >> 评估板 - 线性稳压器 (LDO) 系列:* 产品变化通告:1Q2012 Discontinuation 30/Mar/2012 设计资源:NCP590MNDPTAGEVB Gerber Files 标准包装:1 系列:- 每 IC 通道数:2 - 双 输出电压:1.8V,2.8V 电流 - 输出:300mA 输入电压:2.1 ~ 5.5 V 稳压器类型:正,固定式 工作温度:-40°C ~ 85°C 板类型:完全填充 已供物品:板 已用 IC / 零件:NCP590MNDP 其它名称:NCP590MNDPTAGEVB-NDNCP590MNDPTAGEVBOS
ADP124RHZ-REDYKIT 功能描述:REDYKIT 2.8/3.3 ADP124 RoHS:是 类别:编程器,开发系统 >> 评估板 - 线性稳压器 (LDO) 系列:Redykit™ 产品变化通告:1Q2012 Discontinuation 30/Mar/2012 设计资源:NCP590MNDPTAGEVB Gerber Files 标准包装:1 系列:- 每 IC 通道数:2 - 双 输出电压:1.8V,2.8V 电流 - 输出:300mA 输入电压:2.1 ~ 5.5 V 稳压器类型:正,固定式 工作温度:-40°C ~ 85°C 板类型:完全填充 已供物品:板 已用 IC / 零件:NCP590MNDP 其它名称:NCP590MNDPTAGEVB-NDNCP590MNDPTAGEVBOS
ADP125 制造商:AD 制造商全称:Analog Devices 功能描述:5.5 V Input, 500 mA, Low Quiescent Current, CMOS Linear Regulators
ADP1250001RHZR 制造商:Analog Devices 功能描述: