ICL7665SACPAZ Intersil, ICL7665SACPAZ Datasheet - Page 11

• Manufacturer Part Number: ICL7665SACPAZ
• Description: IC VOLT DETECTOR OVER/UND 8-DIP
• Manufacturer: Intersil
• Type: Multi-Voltage Supervisorr

Specifications of ICL7665SACPAZ

• Number Of Voltages Monitored: 2
• Output: Open Drain or Open Collector
• Reset: Active High
• Voltage - Threshold: Adjustable/Selectable
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Reset Timeout: -

Simple High/Low Temperature Alarm
Figure 16 illustrates a simple high/low temperature alarm
which uses the ICL7665S with an NPN transistor. The
voltage at the top of R
transistor and the position of R
has a negative temperature coefficient. R
that V
temperature reaches the temperature selected for the high
temperature alarm. When this occurs, OUT2 goes low. R
adjusted so that V
transistor’s temperature reaches the temperature selected
for the low temperature alarm. When the temperature drops
below this limit, OUT1 goes low.
UNREGULATED
SET2
DC INPUT
equals 1.3V when the NPN transistor’s
SET1
1
is determined by the V
equals 1.3V when the NPN
FIGURE 15. POWER FAIL WARNING AND POWERUP/POWERDOWN RESET
11
1
’s wiper arm. This voltage
715kΩ
1
5.86kΩ
is adjusted so
130kΩ
BE
4700µF
of the
2
HYST1
V
OUT1
ICL7665S
is
SET1
5V REGULATOR
ICL7665S
7805
V+
AC Power Fail and Brownout Detector
Figure 17 shows a circuit that detects AC undervoltage by
monitoring the secondary side of the transformer. The
capacitor, C
With a normal 100 VAC input to the transformer, OUT1 will
discharge C
When the AC input voltage is reduced, OUT1 will stay OFF,
so that C
reaches 1.3V, OUT2 turns OFF and the power fail warning
goes high. The time constant, R
takes longer than 16.7ms to charge C
HYST2
V
OUT2
SET2
1
does not discharge. When the voltage on C
1
1
, is charged through R
once every cycle, approximately every 16.7ms.
1MΩ
22MΩ
470µF
2.2MΩ
1
C
1MΩ
1
1
, is chosen such that it
when OUT1 is OFF.
1
1MΩ
1.3V.
BACKUP
BATTERY
RESET OR
WRITE
ENABLE
POWER
FAIL
WARNING
April 5, 2006
FN3182.8
1