LTC6991IDCB#TRMPBF Linear Technology, LTC6991IDCB#TRMPBF Datasheet - Page 15

• Manufacturer Part Number: LTC6991IDCB#TRMPBF
• Description: IC TIMERBLOX OSCILLATOR 6-DFN
• Manufacturer: Linear Technology

Specifications of LTC6991IDCB#TRMPBF

• Frequency: *
• Voltage - Supply: *
• Current - Supply: 135µA
• Operating Temperature: *
• Package / Case: 6-WFDFN Exposed Pad
• Count: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

applicaTions inForMaTion
LTC6991 as “Wake-Up Timer”
The output latch reset function provided by the RST pin
allows the LTC6991 to enable a larger system at regular
intervals. The on-time can be controlled by the system.
This allows the system to shut itself down immediately after
performing its tasks, reducing power consumption.
Figure 12 shows an example using “black boxes” for a
switching regulator and the system being duty-cycled.
In some cases, an RC filter may be necessary at the RST
LTC6991 OUT
DONE/RST
V
REG
3V TO 20V
R
4.99k
t
1N4733A
5.1V
SUPPLY
ON
Figure 12. Powering Up a System Once an Hour
THE SYSTEM CAN EXTEND t
t
OUT
R1
1M
R2
681k
R
665k
SET
0.1µF
ON
3570 SECONDS
V
DIV
SET
t
ON
+
AS LONG AS NEEDED (UP TO 50% OF t
LTC6991
input to filter start-up glitches from the system as it is
powered on.
If the LTC6991 is enabling a switching regulator that can
operate on supplies greater than 5.5V, it will be necessary
to limit the supply voltage provided to the LTC6991. If
the LTC6991 output is not heavily loaded, and if a large
R
larger than 100µA, so a simple regulator circuit can be
constructed using a Zener diode.
t
OUT
t
OUT
SET
GND
OUT
RST
resistor is used, the supply current will not be much
C
0.1µF
V
SHDN
FILT
IN
REGULATOR
SWITCHING
R
100k
FILT
t
ON
t
OUT
V
OUT
DONE
OUT
SYSTEM
V
)
REG
V
+
6991 F12
LTC6991

6991f