lx1668 Microsemi Corporation, lx1668 Datasheet - Page 5

• Manufacturer Part Number: lx1668
• Description: Programmable Multiple Output Dc Dc Controller
• Manufacturer: Microsemi Corporation

Copyright © 1999
Rev. 1.0
V
2.5V
OUT3
+5V
4/99
100
95
90
85
80
75
70
1
VID[0:4]
PWRGD
2
OVP
V
V
OUT2
L
CC3
DRV
L
Non-Synchronous Operation, V
FB
FIGURE 1 — Efficiency Test Results:
14
13
10
11
12
5
4
6
7
8
9
3
EFFICIENCY AT 3.1V
EFFICIENCY AT 2.8V
EFFICIENCY AT 1.8V
V
4
REF
Power Good
& OVP
5
DAC
6
SS/ENABLE
2.5V
1.5V
I
V
7
OUT
P
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
SET
ROGRAMMABLE
(A)
17
8
15
R
20k
SS
C
V
SS
CORE
60mV
9
P
40mV
10
R O D U C T I O N
16
C H A R A C T E R I S T I C S C U R V E S
IN
Error Comp
CS Comp
V
= 5V
FB
11
Hiccup
12
FIGURE 3 — Block Diagram
M
B L O C K D I A G R A M
U LTIPLE
I
RESET
13
V
RESET
Hiccup
14
O
Set
UTPUT
R
S
PWM
D
Q
Q
Off-Time
A T A
Control
100
95
90
85
80
75
70
1
DC:DC C
2
S
H E E T
3
FIGURE 2 — Efficiency Test Results:
Synchronous Operation, V
UVLO
EFFICIE NCY A T 3.1V
EFFICIE NCY A T 2.8V
EFFICIE NCY A T 1.8V
ONTROLLER
4
5
UVLO
6
I
7
OUT
(A)
8
19
20
18
2
1
3
9
V
TDRV
BDRV
PGND
AGND
V
+12V
+5V
CC12
CC5
IN
10
= 5V
V
IN
(5V)
11
LX1668
L
12
C
IN
13
R
C
SENSE
ESR
OUT
14
V
CORE
5