Datasheet

LTC1727/LTC1728
3
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elecTrical cHaracTerisTics
All except LTC1728-1.8/LTC1728-3.3. The l denotes specifications which
apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C. V
CC3
= 3.3V, V
CC5
= 5V,
V
CC25
= 2.5V, V
CCA
= V
CC3
unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
VCC3
V
CC3
Supply Current V
CC5
/V
CC25
> V
CC3
V
CC5
/V
CC25
< V
CC3
, V
CC3
= 3.3V (Note 4)
l
l
1
10
2
20
µA
µA
I
VCC25
V
CC25
Supply Current V
CC25
< V
CC3
, V
CC25
= 2.5V (Note 4)
l
1 2 µA
I
VCC5
V
CC5
Supply Current V
CC5
= 5V, V
CC3
< V
CC5
l
10 20 µA
I
VCCA
V
CCA
Input Current V
CCA
= 1V
–40°C < T
A
< 125°C
l
l
–15
–20
0
0
15
50
nA
nA
t
RST
Reset Pulse Width RST Low with 10k Pull-Up to V
CC3
(Note 5)
–40°C < T
A
< 125°C
l
l
140
140
200 280
350
ms
ms
t
UV
V
CC
Undervoltage Detect to RST
or COMPX
V
CC5
, V
CC25
, V
CC3
or V
CCA
Less Than Reset
Threshold V
RT
by More Than 1% (Note 5)
110 µs
V
OL
Output Voltage Low, RST, COMPX I
SINK
= 2.5mA, V
CC3
= 3V, V
CC5
/V
CC25
= 0V
I
SINK
= 100µA, V
CC3
= 1V, V
CC5
/V
CC25
= 0V
I
SINK
= 100µA, V
CC3
= 0V, V
CC5
/V
CC25
= 1V
I
SINK
= 100µA, V
CC3
= 1V, V
CC5
/V
CC25
= 1V
l
l
l
l
0.15
0.05
0.05
0.05
0.4
0.3
0.3
0.3
V
V
V
V
V
OH
Output Voltage High, RST, COMPX (Note 6) I
SOURCE
= 1µA
l
V
CC3
– 1 V
LTC1727-5/LTC1728-5 Only
V
OVR
V
CC5
Reset Override Voltage (Note 7) Override V
CC5
Ability to Assert RST V
CC3
±0.025 V
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
RT3
Reset Threshold V
CC3
V
CC3
Input Threshold
l
2.760 2.805 2.850 V
V
RT18
Reset Threshold V
CC18
V
CC18
Input Threshold
l
1.656 1.683 1.710 V
V
RTA
Reset Threshold V
CCA
V
CCA
Input Threshold
l
0.985 1.000 1.015 V
V
CCOP
V
CC3
, V
CC18
Operating Voltage RST in Correct Logic State
l
1 7 V
I
VCC3
V
CC3
Supply Current V
CC18
> V
CC3
V
CC18
< V
CC3
, V
CC3
= 3V (Note 4)
l
l
1
10
2
20
µA
µA
I
VCC18
V
CC18
Supply Current V
CC18
< V
CC3
, V
CC18
= 1.8V (Note 4)
l
1 2 µA
I
VCCA
V
CCA
Input Current V
CCA
= 1V
l
–15 0 15 nA
t
RST
Reset Pulse Width RST Low (Note 5)
l
140 200 280 ms
t
UV
V
CC
Undervoltage Detect to RST V
CC18
, V
CC3
or V
CCA
Less Than Reset (Note 5)
Threshold V
RT
by More Than 1%
110 µs
V
OL
Output Voltage Low, RST I
SINK
= 2.5mA, V
CC3
= 3V, V
CC18
= 0V
I
SINK
= 100µA, V
CC3
= 1V, V
CC18
= 0V
I
SINK
= 100µA, V
CC3
= 0V, V
CC18
= 1V
I
SINK
= 100µA, V
CC3
= 1V, V
CC18
= 1V
l
l
l
l
0.15
0.05
0.05
0.05
0.4
0.3
0.3
0.3
V
V
V
V
V
OH
Output Voltage High, RST I
SOURCE
= 1µA (Note 6)
l
V
CC3
– 1 V
LTC1728-1.8 The l denotes specifications which apply over the full operating temperature range, otherwise specifications are at
T
A
= 25°C. V
CC3
= 3V, V
CC18
= 1.8V, V
CCA
= V
CC3
unless otherwise noted.