LTC2978
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
J
= 25°C. V
PWR
= V
IN_SNS
= 12V; V
DD33
, V
DD25
and REF pins floating, unless
otherwise indicated. C
VDD33
= 100nF C
VDD25
= 100nF and C
REF
= 100nF
,
.
SYMBOL
t
RESETB
t
WDI
f
WDI
C
IN
V
IH
V
IL
t
LOW
t
RISE
I
LEAK
C
IN
V
OL
PARAMETER
Pulse Width to Assert Reset
Pulse Width to Reset Watchdog Timer
Watchdog Interrupt Input Frequency
Digital Input Capacitance
High Level Input Voltage
Low Level Input Voltage
Assertion Low Time
Rise Time
Input Leakage Current
Input Capacitance
Digital Output Low Voltage
I
SINK
= 3mA
5.49kΩ Pull-Up to V
DD33
l
l
l
l
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
V
WDI/RESETB
≤ 1.5V
V
WDI/RESETB
≤ 1.5V
l
l
l
MIN
300
0.3
TYP
MAX
200
1
UNITS
µs
µs
MHz
pF
V
10
1.6
0.8
90
0.825
110
1.1
450
±1
10
0.4
90
V
DD33
– 0.5
0.5
±95
±24
10
l
l
l
l
l
l
l
l
l
l
Digital Input SHARE_CLK
V
kHz
µs
ns
µA
pF
V
kHz
V
V
µA
µA
pF
400
kHz
µs
µs
µs
ns
ns
ns
ns
900
ns
ns
98
l
l
f
SHARE_CLK_IN
Input Frequency Operating Range
V
SHARE_CLK
< 0.8V
V
SHARE_CLK
< 0.8V to V
SHARE_CLK
> 1.6V
0V ≤ V
SHARE_CLK
≤ V
DD33
+ 0.3V
l
l
l
Digital Outputs SDA, ALERTB, PWRGD, SHARE_CLK, FAULTB00, FAULTB01, FAULTB10, FAULTB11
f
SHARE_CLK_OUT
Output Frequency Operating Range
Digital Inputs ASEL0,ASEL1
V
IH
V
IL
I
IH,IL
I
IH, Z
C
IN
f
SCL
t
LOW
t
HIGH
t
BUF
t
HD,STA
t
SU,STA
t
SU,STO
t
HD,DAT
Input High Threshold Voltage
Input Low Threshold Voltage
High, Low Input Current
Hi-Z Input Current
Input Capacitance
Serial Clock Frequency (Note 10)
Serial Clock Low Period (Note 10)
Serial Clock High Period (Note 10)
Bus Free Time Between Stop and Start
(Note 10)
Start Condition Hold Time (Note 10)
Start Condition Setup Time (Note 10)
Stop Condition Setup Time (Note 10)
Data Hold Time (LTC2978 Receiving
Data) (Note 10)
Data Hold Time (LTC2978 Transmitting
Data) (Note 10)
t
SU,DAT
t
SP
t
TIMEOUT_BUS
Data Setup Time (Note 10)
Pulse Width of Spike Suppressed
(Note 10)
Time Allowed to Complete any PMBus Longer Timeout = 0
Command After Which Time SDA Will Longer Timeout = 1
Be Released and Command Terminated
10
1.3
0.6
1.3
600
600
600
0
300
100
ASEL[1:0] = 0, V
DD33
l
l
l
l
100
110
Serial Bus Timing Characteristics
ns
35
280
ms
ms
25
200
2978fc
8
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
