LTC2953IDD-1#PBF Linear Technology, LTC2953IDD-1#PBF Datasheet - Page 18

• Manufacturer Part Number: LTC2953IDD-1#PBF
• Description: IC PB ON/OFF CONTROLLER 12DFN
• Manufacturer: Linear Technology

Specifications of LTC2953IDD-1#PBF

• Applications: Push Button, On/Off Controller
• Voltage - Supply: 2.7 V ~ 27 V
• Current - Supply: 14µA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 12-DFN
• Ic Function: Push Button On/Off Controller With Voltage Monitoring
• Supply Voltage Range: 2.7V To 27V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: DFN
• No. Of Pins: 12
• Svhc: No
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -

LTC2953
TYPICAL APPLICATIONS
Dual Supply Monitor with μP Reset
The circuit of Figure 22 monitors two supplies and provides
a μP reset. When either the ⎯ P ⎯ F ⎯ I or the VM input voltage
falls below its threshold (0.5V), the ⎯ R ⎯ S ⎯ T output is asserted
low. ⎯ R ⎯ S ⎯ T remains low for 200ms after both inputs rise
above 0.5V. The low leakage ⎯ P ⎯ F ⎯ O output allows for large
valued external resistors.
Reverse Battery Protection
To protect the LTC2953 from a reverse battery connec-
tion, place a 1k resistor (R8) in series with the V
See Figure 23.
18
V2
V1
ON/OFF
+
8.4V
Figure 23. Reverse Battery Protection Using R8
PFI
PFO
VM
Figure 22. Dual Supply Monitor with μP Reset
LTC2953
0.5V
PB
–
+
LTC2953-1
V
IN
R8
1k
–
+
EN
0.5V
910k
R5
RST
2953 F22
V
SHDN
IN
LT1761
V
2953 F23
OUT
RST
IN
μP
pin.
40V TRANSIENTS
Operation with Supply Transients over 40V
The application circuit of Figure 24 operates from a 24V
nominal supply, but can withstand supply transients as
high as 40V.
The high voltage ⎯ E ⎯ N output of the LTC2953-2 has an ab-
solute maximum rating of 50V, which makes it suitable for
driving the gate of the external power PFET. The external
30V Zener diode (Z1) and the 10k current limiting resistor
(RZ) protect the V
that under normal 24V operation, the external Zener diode
does not conduct any current. The voltage drop across
RZ should be kept below 1V. Z2 should have a breakdown
voltage smaller than the PFET’s gate-to-source breakdown
voltage.
Power Path Controller with Low Battery Detect
The application in Figure 25 uses the push button to
completely disconnect the load from the battery. If the
battery voltage falls below the user specifi ed threshold, the
push button is prevented from turning on system power
(asserting the enable output).
24V NOMINAL,
BZX84C30
30V
Figure 24. Operation with 40V Supply Transients
Z1
ON/OFF
RZ
10k
IN
1μF
50V
supply pin of the LTC2953-2. Note
V
PB
IN
LTC2953-2
BZX84C10
R5
100k
10V
Z2
2953 F24
EN
R9
100k
50V
ABS MAX
FDS4685
Si2319DS
NDS9407
2953f