ltc2978 Linear Technology Corporation, ltc2978 Datasheet - Page 12

• Manufacturer Part Number: ltc2978
• Description: Octal Pmbus Power Supply Monitor And Controller With Eeprom
• Manufacturer: Linear Technology Corporation

LTC2978
Typical perForMance characTerisTics
pin FuncTions
PIN NAME
V
V
V
V
V
V
V
V
V
V
V
V
DNC
V
V
V
V
V
WP
PWRGD
SHARE_CLK
WDI/RESET

SENSEM6
SENSEP7
SENSEM7
OUT_EN0
OUT_EN1
OUT_EN2
OUT_EN3
OUT_EN4
OUT_EN5
OUT_EN6
OUT_EN7
IN_EN
IN_SNS
PWR
DD33
DD33
DD25
PIN NUMBER
1.2
1.0
0.8
0.6
0.4
0.2
0
PWRGD and FAULTBzn V
vs Current
0
1*
2*
3*
10
11
12
13
14
15
16
17
18
19
20
21
22
4
5
6
7
8
9
2
Do Not Connect Do Not Connect to This Pin
4
PIN TYPE
In/Out
In/Out
In/Out
I
SINK
Out
Out
Out
Out
Out
Out
Out
Out
Out
0ut
In
In
In
In
In
In
In
In
6
(mA)
8
DESCRIPTION
DC/DC Converter Differential (–) Output Voltage-6 Sensing Pin
DC/DC Converter Differential (+) Output Voltage or Current-7 Sensing Pin
DC/DC Converter Differential (–) Output Voltage or Current-7 Sensing Pin
DC/DC Converter Enable-0 Pin. Output High Voltage Optionally Pulled Up to 12V by 5µA
DC/DC Converter Enable-1 Pin. Output High Voltage Optionally Pulled Up to 12V by 5µA
DC/DC Converter Enable-2 Pin. Output High Voltage Optionally Pulled Up to 12V by 5µA
DC/DC Converter Enable-3 Pin. Output High Voltage Optionally Pulled Up to 12V by 5µA
DC/DC Converter Open-Drain Pull-Down Output-4
DC/DC Converter Open-Drain Pull-Down Output-5
DC/DC Converter Open-Drain Pull-Down Output-6
DC/DC Converter Open-Drain Pull-Down Output-7
DC/DC Converter V
V
Determine When to Enable and Disable, Respectively, the Downstream DC/DC Converters
V
Voltage is Unavailable, Short V
If Shorted to V
Regulated Voltage Output (Use 100nF Decoupling Capacitor to GND)
Input for Internal 2.5V Sub-Regulator. Short This Pin to Pin 16
2.5V Internally Regulated Voltage Output. Bypass to GND with a 0.1µF Capacitor
Digital Input. Write-Protect Input Pin, Active High
Power Good Open-Drain Output. Indicates When Outputs are Power Good. Can be Used as System
Power-On Reset
Bidirectional Clock Sharing Pin. Connect a 5.49k Pull-Up Resistor to V
Watchdog Timer Interrupt and Chip Reset Input. Connect a 10k Pull-Up Resistor to V
Resets Watchdog Counter. Holding This Pin Low for More Than t
OL
IN
PWR
SENSE Input. This Voltage is Compared Against the V
10
85°C
25°C
–40°C
Serves as the Unregulated Power Supply Input to the Chip (4.5V to 15V). If a 4.5V to 15V Supply
2978 G34
12
PWR
, it Serves as 3.13V to 3.47V Supply Input Pin. Otherwise it is a 3.3V Internally
IN
ENABLE Pin. Output High Voltage Optionally Pulled Up to 12V by 5µA
PWR
to V
1.4
1.2
1.0
0.8
0.6
0.4
0.2
DD33
0
0
ALERTB V
and Power the Chip Directly from a 3.3V Supply
2
OL
4
25°C
vs Current
IN
I
SINK
On and Off Voltage Thresholds in Order to
6
–40°C
(mA)
85°C
RESETB
8
DD33
Resets the Chip
10
2978 G35
12
DD33
. Rising Edge
2978fa