ltc693csw-trpbf Linear Technology Corporation, ltc693csw-trpbf Datasheet - Page 16

• Manufacturer Part Number: ltc693csw-trpbf
• Description: Microprocessor Supervisory Circuits
• Manufacturer: Linear Technology Corporation

APPLICATIONS INFORMATION
TYPICAL APPLICATIONS
LTC692/LTC693
Pushbutton Reset
The LTC692/LTC693 do not provide a logic input for direct
connection to a pushbutton. However, a pushbutton in
series with a 100Ω resistor connected to the RESET output
pin (Figure 13) provides an alternative for manual reset.
Connecting a 0.1μF capacitor to the RESET pin debounces
the pushbutton input.
The 100Ω resistor in series with the pushbutton is required
to prevent the ringing, due to the capacitance and lead
inductance, from pulling the RESET pins of the MPU and
LTC692/LT693 below ground.
16
R2
30k
R1
10k
1
Capacitor Backup with 74HC4016 Switch
74HC4016
10
7
11
12
13
14
5V
2
+
100μF
0.1μF
V
V
CC
BATT
LTC693
GND
LOW LINE
V
OUT
692_3 • TA03
0.1μF
0.1μF
5V
3V
5V
V
V
CC
BATT
V
CC
Figure 13. The External Pushbutton Reset
LTC693
LTC692
LTC693
GND
Write Protect for Additional RAMs
GND
LOW LINE
CE OUT
RESET
CE IN
V
OUT
CS
20ns PROPAGATION
DELAY
A
+
0.1μF
OPTIONAL CONNECTION FOR
ADDITIONAL RAMs
10μF
CS
CS
B
C
100Ω
0.1μF
0.1μF
0.1μF
RESET
(e.g. 6805)
MPU
CS
CS
CS
CS
CS
692_3 • F13
V
V
V
CC
CC
CC
62512
RAM
1
2
1
62128
RAM
2
62128
RAM
692_3 • TA04
A
B
0692fa
C