MIC2178_05 Datasheet, PDF (14/15 Pages) Micrel Semiconductor – 2.5A Synchronous Buck Regulator

MIC2178
Micrel, Inc.
Q1
SI9435
V_IN
D
S
4.5V to 16.5V
C1
G _22µF
35V
R1
20k
Skip Mode
PWM Mode
U1
1,2,9
VIN
20 _EN
3,8
SW
11 _PWRGD
4–7
MIC2178 PGND
10 _PWM
18 _SYNC
FB ¹²
COMP SGND BIAS
13
R2
10k
C4
6.8nF
14–17
19
C3
0.01µF
L1
50µH
D1
MBRS130L
V_OUT
3.3V/1A
C2
100µF
10V
C3
0.01µF
U1 Micrel MIC2178-3.3BWM
C1 AVX
TPSE226M035R0300, ESR = 0.3Ω
C2 AVX
TPSD107M010R0100, ESR = 0.1Ω
C3 Z5UorX7R Ceramic Dielectric Material
C4 X7RorNP0 Ceramic Dielectric Material
D1 Motorola MBRS130LT3
Q1 Siliconix Si9435DY PMOS
L1 Coiltronics CTX50-4P, DCR = 0.097 Ω
L1 Coilcraft DO3316-473, DCR = 0.12Ω
L1 Bi
HM77-11003, DCR = 0.073Ω
V_IN
8V to 16.5V
Figure 6. MIC2178 Reversed Battery Protected Regulator
C1
22µF
35V
R1
20k
Skip Mode
PWM Mode
U1
1,2,9
20 _EN
VIN
3,8
SW
11 _PWRGD
4–7
10
MIC2178
PWM
PGND
18 _SYNC
FB ¹²
COMP SGND BIAS
13
R2
10k
C6
6.8nF
14–17
19
C5
0.01µF
U1 Micrel MIC2178-5.0BWM
C1 AVX
TPSE226M035R0300, ESR = 0.3Ω
C2 AVX
TPSD107M010R0100, ESR = 0.1Ω
C3 AVX
TPSD107M010R0100, ESR = 0.1Ω
C4 AVX
TPSD107M010R0100, ESR = 0.1Ω
C5 Z5UorX7R Ceramic Dielectric Material
C6 X7RorNP0 Ceramic Dielectric Material
D1 Motorola MBRS130LT3
D2 Motorola MBRS130LT3
L1 Coiltronics CTX50-4P, DCR = 0.097 Ω
D1
MBRS130L
T1
50µH
2
1
+V_OUT/+IOUT
5V/0.5A
C2
100µF
10V
C4
100µF
10V
R3
10k
4
3
D2
MBRS130L
C2
100µF
10V
–V_OUT/-I_OUT
–5V/0.5A
+I_OUT + (–I_OUT ) 1A
DC = + ^VOUT
V_IN
DC 40% then – I_OUT
DC 40% then – I_OUT
+ I_OUT
+ I_OUT
(1– DC)
Figure 7. MIC2178 8V–16.5V to ±5V/500mA Regulator
M9999-031805
14
March 2005