Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF HTML

HA17384SPS Datasheet(PDF) 28 Page - Hitachi Semiconductor

Part No. HA17384SPS
Description  High Speed Current Mode PWM Control IC for Switching Power Supply
Download  31 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  HITACHI [Hitachi Semiconductor]
Homepage  http://www.renesas.com/eng
Logo 

HA17384SPS Datasheet(HTML) 28 Page - Hitachi Semiconductor

 
Zoom Inzoom in Zoom Outzoom out
 28 / 31 page
background image
HA17384SPS/SRP, HA17384HPS/HRP, HA17385HPS/HRP
28
Notice for Use
1. OVP Latch Block
• Case
When DC power is applied directly as the power supply of the HA17384H, HA17385H, without using
the transformer backup coil. Also, when high-frequency noise is superimposed on the V
IN pin.
• Problem
The IC may not be turn on in the case of a circuit in which V
IN rises quickly (10 V/100 µs or faster),
such as that shown in figure 16. Also, the OVP latch may operate even though the FB pin is normally at
V
OVP or below after the IC is activated.
• Reason
Because of the IC circuit configuration, the timer latch block operates first.
• Remedy (counter measure)
Take remedial action such as configuring a time constant circuit (R
B, CB) as shown in figure 17, to keep
the V
IN rise speed below 10 V/100 µs. Also, if there is marked high-frequency noise on the VIN pin, a
noise cancellation capacitor (C
N) with the best possible high-frequency characteristics (such as a
ceramic capacitor) should be inserted between the V
IN pin and GND, and close to the VIN pin.
When configuring an IC power supply with an activation resistance and backup winding, such as an
AC/DC converter, the rise of V
IN will normally be around 1 V/100 µs, and there is no risk of this problem
occurring, but careful attention must be paid to high-frequency noise.
Also, this phenomenon is not occuring to the HA17384S, because OVP function is not built-in.
Output
Input
VIN
VIN
GND
Feedback
HA17384
Series
Figure 16 Example of Circuit with Fast V
IN Rise Time


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn