Datasheet

MAX6819/MAX6820
SOT23 Power-Supply Sequencers
_______________________________________________________________________________________ 7
SETD/ENSETV
V
CC2
GATE
MULTISUPPLY
BOARD OR µP
5(V) PRIMARY VOLTAGE SUPPLY
3.3(V) SECONDARY VOLTAGE SUPPLY
1.8(V) THIRD VOLTAGE SUPPLY
V
CC1
GND
R
3
R
4
R
1
R
2
SETD/ENSETV
V
CC2
GATE
V
CC1
GND
MAX6819
MAX6820
MAX6819
MAX6820
Figure 4. Sequencing Three Power Supplies
Figure 5. Maximum Transient Duration vs. SETV Threshold
in Overdrive
18
0
0.01 10.1
6
2
14
10
20
8
4
16
12
SETV THRESHOLD OVERDRIVE, V
TH
- V
SETV
(V)
MAXIMUM TRANSIENT DURATION (µs)
V
CC1
= 5V
V
CC2
= 0
SETD = FLOATING
GATE DISABLED ABOVE CURVE
10%
O
V
EN
/V
SETV
t
DELAY
t
ON
90%
10%
V
CC2
+ 5.5V
GATE
O
t
OFF
50%
Figure 3. Timing Diagram