LTC1773 Datasheet, PDF (16/20 Pages) Linear Technology – Synchronous Step-Down DC/DC Controller

LTC1773
TYPICAL APPLICATIONS
33pF
30k
0.1µF
200pF
LTC1773
1
10
I_TH
SW
2 _{RUN/SS SENSE–} 9
3
V_{IN SYNC/FCB}
4
V_FB
5
GND
8
V_IN
7
TG
6
BG
R_SENSE
0.025Ω
Si9803DY
47µF
L1
2µH
Si9804DY
80.6k
1%
249k
1%
L1
2µH
2.7V ≤ V_IN ≤ 4.2V
V_OUT
3.3V
1A
+
+ C_OUT
220µF
6.3V
C_IN
150µF
6.3V
C_IN: SANYO POSCAP 6TPA150M
C_OUT: AVX TPSD227M006R0100
L1: COILTRONICS CTX2-4/BH ELECTRONICS 511-1010
R_SENSE: IRC LR1206-01-R033-F
1773 TA03
Figure 10. Single Lithium-Ion to 3.3V/1A Synchronous Zeta Converter
Efficiency Curve for Figure 10
100
V_OUT = 3.3V
90
V_IN = 5V
V_IN = 4V
80
V_IN = 3.3V
70
V_IN = 2.7V
60
50
40
30
20
0.001
0.01
0.1
OUTPUT CURRENT (A)
1.0
1773 G18
1773fb
16