 |
전자부품 데이터시트 검색엔진 |
|
|
전자부품 데이터시트 검색엔진 |
|
SC4524ASETRT 데이터시트(PDF) 14 Page - Semtech Corporation |
|
|
|||||||||||||||||||||||||||||
SC4524ASETRT 데이터시트(HTML) 14 Page - Semtech Corporation |
|
|
14 / 19 page  (3) Place the compensator zero, F Z, between 0% and 20% of the crossover frequency, F C. (4) Use the compensator pole, F P, to cancel the ESR zero, F Z. (5) Then, the parameters of the compensation network can be calculated by where g m=0.28mA/V is the EA gain of the SC4524A. Example: Determine the voltage compensator for an 800kHz, 2V to 3.3V/2A converter with 22uF ceramic output capacitor. Choose a loop gain crossover frequency of 80kHz, and place voltage compensator zero and pole at F Z=6kHz (20% of F C), and FP=600kHz. From Equation (9), the required compensator gain at F C is Then the compensator parameters are Select R 7=22.k, C5=0.47nF, and C8=0pF for the design. Compensator parameters for various typical applications are listed in Table 4. A MathCAD program is also available upon request for detailed calculation of the compensator parameters. CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = CESAT D IN D O V V V V V D − + + = − = V 0 . V R R O 6 4 SW D O L L F ) D ( ) V V ( I ⋅ − ⋅ + = D SW O D O F I % 20 ) D ( ) V V ( L ⋅ ⋅ − ⋅ + = ) D ( D I I O CIN _ RMS − ⋅ ⋅ = ⋅ ⋅ + ⋅ D = D O SW L O C F 8 ESR I V SW IN O IN F V 4 I C ⋅ D ⋅ > , R G R G S CA PWM ⋅ ≈ ) / s Q / s () / s ( ) C R s ( G V V 2 n 2 n p O ESR PWM c o ω + ω + ω + + = 7 Z 5 R F 2 C π = 7 P 8 R F 2 C π = , C R O p ≈ ω , C R O ESR Z = ω k 3 . 22 0 28 . 0 0 R 3 7 20 9 . 5 = ⋅ = − nF 45 . 0 0 . 22 0 6 2 C 3 3 5 = ⋅ ⋅ ⋅ ⋅ π = pF 2 0 . 22 0 600 2 C 3 3 8 = ⋅ ⋅ ⋅ ⋅ π = ⋅ π ⋅ ⋅ − = O FB O C S CA C V V C F 2 R G log 20 A dB 9 . 5 3 . 3 0 . 0 22 0 80 2 0 . 6 28 log 20 A 6 3 3 C = ⋅ ⋅ ⋅ ⋅ ⋅ π ⋅ ⋅ ⋅ ⋅ − = − − m 7 g 0 R 20 C A = Thermal Considerations For the power transistor inside the SC4524A, the conduction loss P C, the switching loss PSW, and bootstrap circuit loss P BST, can be estimated as follows: (0) whereV BST is the BST supply voltage and tS is the equivalent switching time of the NPN transistor (see Table 3). Table 3. Typical switching time In addition, the quiescent current loss is () The total power loss of the SC4524A is therefore (2) The temperature rise of the SC4524A is the product of the total power dissipation (Equation (2)) and q JA (36 o C/W), which is the thermal impedance from junction to ambient for the SOIC-8 EDP package. It is not recommended to operate the SC4524A above 25oC junction temperature. In the applications with high input voltage and high output current, the switching frequency may need to be reduced to meet the thermal requirement. O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = O CESAT C I V D P ⋅ ⋅ = 40 I V D P O BST BST ⋅ ⋅ = DC 2 O IND R I ) 3 . ~ . ( P ⋅ ⋅ = O D D I V ) D ( P ⋅ ⋅ − = SW O IN S SW F I V t 2 P ⋅ ⋅ ⋅ ⋅ = Q BST SW C TOTAL P P P P P + + + = mA 2 V P IN Q ⋅ = 1A 2A 12V 12.5ns 15.3ns 24V 22ns 25ns 28V 25.3ns 28ns Load Current Input Voltage SC4524A 4 Applications Information (Cont.) |
|
|
링크 URL |
| ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크 투 데이터시트 | 링크교환 | 제조사별 검색 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 |
Korean ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
