Electronic Components Datasheet Search |
|
ACE70335AN+ Datasheet(PDF) 8 Page - ACE Technology Co., LTD. |
|
ACE70335AN+ Datasheet(HTML) 8 Page - ACE Technology Co., LTD. |
8 / 16 page ACE703 Technology White LED PFM Step-Up DC-DC Converter VER 1.2 8 Cf R D Vout Vout r load = Δ = Vout R ax r r ESR • + = Im ' 1 2 1 + = R R V Vout IFB 2 ) 1 ( R V Vout IFB × − Vout Vout I C L Vout L − + ≈ Δ 2 2 (2) Capacitor Selection Ignore ESR of capacitor, the ripple of output voltage is: So large value capacitor is needed to reduce ripple. But too large capacitor value will slow down system reaction and cost will improve. So 100uF capacitor is recommended. Larger capacitor value will be used in large output current system. If output current is small (<10mA), small value is needed. Consider ESR of capacitor, ripple will increase: When current is large, ripple caused by ESR will be main factor. It may be greater than 100mV.The ESR will affects efficiency and increase energy loss. So low-ESR capacitor (for example: tantalum capacitor) is recommend or connect two or more filter capacitors in parallel. (3) Diode Selection Rectifier diode will affects efficiency greatly,Though a common diode (such as 1N4148) will work well for light load, it will reduce about 5%~10% efficiency for heavy load, For optimum performance, a Schottky diode (such as 1N5817.1N5819.1N5822) is recommended. (4) Input Capacitor If supply voltage is stable, the DC-DC circuit can output low ripple, low noise and stable voltage without input capacitor. If voltage source is far away from DC-DC circuit, input capacitor value greater than 10uF is recommended. (5) Resistor R1.R2 for output voltage detect In constant current application,R1 and R2 can be selected by following expression: For example, when VIFB=400mV,Vout=3.3V. If R2=4KΩ,then R1= =29KΩ;if R2=40KΩ,then R1=290 KΩ. (6) Selection of L.C and compensation capacitor C1 When the load current is large(eg: Iout=100mA),the output voltage ripple will increase: As we can see, When output current is large, the maximum current of the inductor IL will increase, thus the ripple of the output voltage will increase. To decrease the ripple, there are two ways: |
Similar Part No. - ACE70335AN+ |
|
Similar Description - ACE70335AN+ |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
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 Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |