参数资料
型号: LA5772MP
元件分类: 稳压器
英文描述: 3.1 A SWITCHING REGULATOR, 192 kHz SWITCHING FREQ-MAX, PSSO5
封装: SMP-5
文件页数: 4/5页
文件大小: 62K
代理商: LA5772MP
LA5772MP
No.8289-4/5
Description of Functional Settings
1.Start delay function
The SS pin has the internally-connected 22
A (typ) constant-current supply. When the voltage of SS pin exceeds the
threshold voltage, the regulator starts operation. As the threshold is 0.62V(typ), the start delay time can be calculated
as follows:
ex. For setting at 1
F
2.Soft start function
The internal PWM waveform has the voltage value as shown in the right.
If down-conversion from the voltage of VIN=20V to 5V output is to be made,
for example, the PWM-ON duty has the value as shown below.
(Note that calculation is made with Vsat=1V and VF=0.2V)
The output voltage of error amplifier, which is 5V, is the value with PWM=27%, as calculated in the above equation, so
that this voltage is determined as follows:
Ver=(
VPWM)×PWMduty+VPWML=0.88V×0.27+0.62V=0.86V
(
VPWM is the PWM amplitude value or 0.88V(typ) while VPWML is the lower limit voltage of PWM
waveform or 0.62V(typ))
SS pin and error amplifier output voltages are designed to prefer the lower voltages, so that VOUT will reach the
designed regulation voltage in timing when the SS pin voltage exceeds the error amplifier output. Therefore, the soft strt
time is calculated as follows:
For the set conditions of C=1
F and PWMduty=27%:
28.2ms
22
62V
0
1
i
V
C
Td
=
Α
.
×
Α
=
×
=
27%
VF
Vsat
-
IN
V
VF
OUT
V
PWMduty
=
+
=
A
22
PWMduty
88V
0
C
i
PWMduty
VPWM
C
Tss
×
.
×
=
×
×
=
ms
8
.
10
A
22
0
88V
0
1
Tss
=
.27
×
.
×
Α
=
1.5V
0.62V
PWM wave
相关PDF资料
PDF描述
LA5779 3.1 A SWITCHING REGULATOR, 192 kHz SWITCHING FREQ-MAX, ZFM5
LA6575H BRUSH DC MOTOR CONTROLLER, 0.7 A, PDSO30
LA6581M BRUSHLESS DC MOTOR CONTROLLER, 0.5 A, PDSO8
LA6584M BRUSHLESS DC MOTOR CONTROLLER, 1.6 A, PDSO16
LA6584M BRUSHLESS DC MOTOR CONTROLLER, 1.6 A, PDSO16
相关代理商/技术参数
参数描述
LA5774 制造商:Distributed By MCM 功能描述:Voltage Mode SMPS Controller Sanyo IC 5-Pin Zip
LA5774-E 功能描述:直流/直流开关调节器 PWR SWITCHING REGULATOR RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
LA5774-FA-E 功能描述:直流/直流开关调节器 RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
LA5774MC-BE 制造商:ON Semiconductor 功能描述:SWITCHING POWER SUPPLY - Tape and Reel 制造商:ON Semiconductor 功能描述:REEL / SWITCHING POWER SUPPLY
LA5774MC-E 制造商:ON Semiconductor 功能描述:SWITCHING POWER SUPPLY - Ammo Pack 制造商:ON Semiconductor 功能描述:FNFLD / SWITCHING POWER SUPPLY