LTC2908
TYPICAL PERFOR A CE CHARACTERISTICS
RST Output Voltage High (V
OH
) vs
RST Output Source Current (I
RST
)
LTC2908-A1
5
RST OUTPUT VOLTAGE HIGH, V
OH
(V)
RST OUTPUT VOLTAGE HIGH, V
OH
(V)
3.0
4
3
25°C
2
V1 = 5.0V
V2 = 3.3V
V3 = 2.5V
V4 = 1.8V
V
ADJ1
= V
ADJ2
= 0.55V
0
–40°C
85°C
1
–4
–12
–16
–20
–8
OUTPUT SOURCE CURRENT, I
RST
(µA)
2908 G21
PI FU CTIO S
(TS8 Package/DDB8 Package)
V2 (Pin 1/Pin 4):
Voltage Input 2. The greater of V1, V2 is
also the internal V
CC
. The operating voltage on this pin
shall not exceed 6V. When in normal operation (V1 > V2),
this pin draws approximately 8µA. When this pin is acting
as the V
CC
(V2 > V1), this pin draws an additional 15µA.
Bypass this pin to ground with a 0.1µF (or greater)
capacitor.
V4 (Pin 2/Pin 3):
Voltage Input 4.
RST (Pin 3/Pin 2):
Reset Logic Output. Pulls low when any
voltage input is below the reset threshold and is held low
for 200ms after all voltage inputs are above threshold. This
pin has a weak pull-up to V
CC
and may be pulled above V
CC
using an external pull-up.
GND (Pin 4/Pin 1):
Device Ground.
6
U W
RST Output Voltage High (V
OH
) vs
RST Output Source Current (I
RST
)
LTC2908-B1
2.5
2.0
25°C
85°C
–40°C
V1 = 3.3V
V2 = 2.5V
1.0 V3 = 1.8V
V4 = 1.5V
V
ADJ1
= V
ADJ2
= 0.55V
0.5
–4
–6
–8
–10
–12
0
–2
OUTPUT SOURCE CURRENT, I
RST
(µA)
2908 G22
1.5
U
U
U
V
ADJ2
(Pin 5/Pin 8):
Adjustable Voltage Input 2. See
Table 1 for recommended ADJ resistors values.
V3 (Pin 6/Pin 7):
Voltage Input 3.
V
ADJ1
(Pin 7/Pin 6):
Adjustable Voltage Input 1. See
Table 1 for recommended ADJ resistors values.
V1 (Pin 8/Pin 5):
Voltage Input 1. The greater of V1, V2 is
also the internal V
CC
. The operating voltage on this pin
shall not exceed 6V. When in normal operation (V1 > V2),
this pin draws approximately 21µA. When this pin is not
acting as the V
CC
(V2 > V1), this pin draws approximately
8µA. Bypass this pin to ground with a 0.1µF (or greater)
capacitor.
Exposed Pad (Pin 9, DDB8 Only):
Exposed Pad may be left
open or connected to device ground.
sn2908 2908fs
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
