LTC1536
ELECTRICAL CHARACTERISTICS
V
CC3
= 3.3V, V
CC5
= 5V, V
CCA
= V
CC3
, T
A
= 25°C unless otherwise noted.
SYMBOL
I
PBR
V
IL
V
IH
t
PW
t
DB
t
PB
V
OL
PARAMETER
PBR Pull-Up Current
PBR, RST Input Low Voltage
PBR, RST Input High Voltage
PBR Min Pulse Width
PBR Debounce
PBR Assertion Time for Transition
from Soft to Hard Reset Mode
RST Output Voltage Low
Deassertion of PBR Input to SRST
Output (PBR Pulse Width = 1µs)
PBR Held Less Than V
IL
, 0°C to 70°C
PBR Held Less Than V
IL
, – 40°C to 85°C
I
SINK
= 5mA
I
SINK
= 100µA
0°C
≤
T
A
≤
70°C
I
SINK
= 100µA
– 40°C
≤
T
A
≤
85°C
SRST Output Voltage Low
RST Output Voltage Low
V
OH
RST Output Voltage High (Note 3)
SRST Output Voltage High (Note 3)
RST Output Voltage High
t
PHL
t
PLH
t
FAIL
t
PF
Propagation Delay RST to RST
High Input to Low Output
Propagation Delay RST to RST
Low Input to High Output
V
CC5
or V
CC3
0.5V Undervoltage
to RST (Note 4)
V
CC5
< (V
CC3
– 300mV) RST (Note 4)
I
SINK
= 2.5mA
I
SINK
= 2.5mA
I
SOURCE
= 1µA
I
SOURCE
= 1µA
I
SOURCE
= 600µA
C
RST
= 20pF
C
RST
= 20pF
V
CC5
Drops Below 4.25V or V
CC3
Drops
Below 2.5V (Note 5)
V
CC5
Drops Below V
CC3
By 300mV
(Note 6)
q
q
CONDITIONS
PBR = 0V, 0°C
≤
T
A
≤
70°C
PBR = 0V, – 40°C
≤
T
A
≤
85°C
q
q
q
q
q
q
q
q
q
MIN
3
3
2
40
TYP
7
7
MAX
10
15
0.8
UNITS
µA
µA
V
V
ns
20
1.4
1.4
2.0
2.0
0.15
0.05
0.05
0.05
0.05
0.05
0.05
0.15
0.15
V
CC3
– 1
V
CC3
– 1
V
CC3
– 1
25
45
150
50
35
2.8
3.0
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
ms
s
s
V
V
V
V
V
V
V
V
V
V
V
V
ns
ns
V
CC3
= 1V, V
CC5
= 0V
V
CC3
= 0V, V
CC5
= 1V
V
CC3
= 1V, V
CC5
= 1V
V
CC3
= 1.1V, V
CC5
= 0V
V
CC3
= 0V, V
CC5
= 1.1V
V
CC3
= 1.1V, V
CC5
= 1.1V
q
q
q
q
q
q
q
q
q
q
q
450
90
ns
ns
The
q
denotes specifications which apply over the full operating
temperature range.
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2:
All voltage values are with respect to GND.
Note 3:
The output pins SRST and RST have weak internal pull-ups to
V
CC3
of 6µA. However, external pull-up resistors may be used when faster
rise times are required.
Note 4:
Conforms to PCI Local Bus Specification Rev 2.1,
Sect. 4.3.2 for t
FAIL
.
Note 5:
V
CC3
or V
CC5
falling at – 0.1V/µs, time measured from
V
RTX
– 500mV to RST at 1.5V.
Note 6:
V
CC5
falling from 5V to 3V in
≤10ns,
time measured from
V
CC5
= (V
CC3
– 300mV) to RST at 1.5V.
3