參數(shù)資料
型號: HA16114PJ
廠商: Hitachi,Ltd.
元件分類: 基準(zhǔn)電壓源/電流源
英文描述: RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
中文描述: 抗輻射高效,5安培開關(guān)穩(wěn)壓器
文件頁數(shù): 11/38頁
文件大?。?/td> 275K
代理商: HA16114PJ
HA16114P/PJ/FP/FPJ, HA16120FP/FPJ
11
3.2 Soft-Start Setting
Soft-start avoids overshoot at power-up by widening the PWM output pulses gradually, so that the
converted DC output rises slowly. Soft-start is programmed by connecting a capacitor between the DB pin
and ground. The soft-start time is determined by the time constant of this capacitor and the resistors that
set the voltage at the DB pin.
V
DB
= Vref
×
V
X
V
DB
R
2
R
1
+ R
2
R =
R
1
×
R
2
R
1
+ R
2
t
soft
=
C
1
×
R
×
ln (1
)
Note:
V
X
is the voltage at the DB pin after time t (V
X
< V
DB
).
+
+
To Vref
R
R
V
X
DB
E/O
PWM
COMP
from
UVL
V
TH
V
TL
1.6 V
1.0 V
t
C
1
Soft-start time
t
soft
Undervoltage
lockout released
V
DB
V
X
UVL sink
transistor
1
2
Sawtooth
wave
Sawtooth wave
Figure 3.2 Soft-Start Setting
3.3 Quick Shutdown
The quick shutdown function resets the voltages at all pins when the IC is turned off, to assure that PWM
pulse output stops quickly. Since the UVL pull-down resistor in the IC remains on even when the IC is
turned off, the sawtooth wave output, error amplifier output, and DB pin are all reset to low voltage.
This feature helps in particular to discharge capacitor C
1
in figure 3.2, which has a comparatively large
capacitance. In intermittent mode (explained on a separate page), this feature enables the IC to soft-start in
each on-off cycle.
相關(guān)PDF資料
PDF描述
HA16120FPJ CAP 1000PF 25V 5% NP0(C0G) SMD-0603 TR-7 PLATED-NI/SN
HA16117FA CMOS Watchdog Timer
HA16117FB CMOS Watchdog Timer
HA16117FC CMOS Watchdog Timer
HA16117FPA CMOS Watchdog Timer
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
HA16116 制造商:HITACHI 制造商全稱:Hitachi Semiconductor 功能描述:Switching Regulator for Chopper Type DC/DC Converter
HA16116FP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:Switching Regulator for Chopper Type DC/DC Converter
HA16116FP/FPJ/ 制造商:未知廠家 制造商全稱:未知廠家 功能描述:HA16116FP/FPJ/ HA16121FP/FPJ Datasheet 443K/SEP.18.03
HA16116FP-E 制造商:Renesas Electronics 功能描述:DC DC Cntrlr Dual-OUT PWM DC to DC Controller/Step Down 20-Pin SOP Bulk