CAT808
Low-Power Precision Voltage Detector
FEATURES
Ultra Low Current Consumption 2.4µA
Accurate Voltage Detection Threshold
Fine Voltage Detection Threshold Resolution
Active Low Open Drain Output
Available in 5-pin TSOT- 23 and 3-pin SOT- 89
RoHS compliant packages
Industrial temperature range -40°C to +85°C
The CAT808 open-drain output is active low until the
V
DD
voltage exceeds the detection threshold. A low
hysteresis is built into the device to minimize output
“chatter”, while V
DD
passes through the detection
threshold, and the output transitions high.
After the CAT808 asserts the output high condition, it
continues to monitor V
DD
until it drops below the
detection threshold, when the output goes low until
V
DD
once again exceeds the detection threshold.
DESCRIPTION
The CAT808 is a high-precision voltage detector
designed for monitoring single cell and multi-cell batteries.
Voltage detection thresholds between 2.0V and 3.2V are
provided with 0.1V resolution and ±3.0% accuracy.
APPLICATIONS
Battery-Powered Systems
Power Supply Monitoring
Handheld and Portable Equipment
Processor Supervisor Reset
For Ordering Information details, see page 7.
PIN CONFIGURATION
SOT-89
OUT 1
V
DD
2
GND 3
TYPICAL APPLICATION
5-Lead Thin SOT-23
V
DD
IN
CAT808
OUT
DC-DC
CONVERTER
SHDN
GND
OUT
OUT 1
V
DD
2
GND 3
5 NC
Battery
Voltage
10kΩ
4 NC
GND
Note:
The value of the pull-up resistor is not critical
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. 3024 Rev. A
CAT808
ABSOLUTE MAXIMUM RATINGS
Parameters
Temperature under Bias
Storage Temperature
Voltage on any Pin with Respect to GND
(2)(3)
V
DD
with Respect to GND
Lead Soldering temperature (10 seconds)
Power Dissipation
TSOT-23-5
SOT-89
(1)
Ratings
-55 to +125
-65 to +150
-2.0 to V
DD
+ 2.0
-2.0 to 7.0
+300
250
500
Units
ºC
ºC
V
V
ºC
mW
mW
RECOMMENDED OPERATING CONDITIONS
Parameters
V
DD
Operating Temperature Range
DC ELECTRICAL CHARACTERISTICS
T
A
= -40ºC to +85ºC, V
DD
= 1.2V to 6.0V
Symbol
V
DET
V
DET
I
DD
Parameter
Detection Voltage, 27
Detection Voltage, 32
Current Consumption
Conditions
T
A
= -40ºC to +85ºC
T
A
= -40ºC to +85ºC
V
DD
= 4.0V
V
DD
= 5.0V
V
DD
= 6.0V
I
OUT
I
LEAK
T
PHL/LH
Δ
- V
DET
ΔT
A
●
-V
DET
Notes:
(1)
Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings
only and functional operation of the devices at these or any other conditions outside of those listed in the operational sections of this
specification is not implied. Exposure to any absolute maximum rating for extended periods may affect device performance and
reliability.
The Minimum DC input voltage is -0.5V. During transitions, inputs may undershoot to -2.0V for periods of less than 20ns. Maximum DC
voltage on output pins is V
CC
+0.5V, which may overshoot to V
CC
+2.0V for periods of less than 20ns.
Latch-up protection is provided for stresses up to 100mA on all pins from -1V to V
CC
+1V.
The temperature change ratio in the detection voltage [ppm/°C] is calculated by using the following equation:
Ratings
+1.2 to +6.0
-40 to +85
Units
V
ºC
Min Typ. Max
2.62
3.12
-
-
-
V
DD
=1.2V
V
DD
=2.4V
0.6
2.9
-
-
-
2.7
3.2
2.4
3.5
5
1.4
5
-
-
2.78
3.28
5
7
10
-
-
1
60
Units
V
µA
Output SinkCurrent
Output Leakage Current
Response Time
Detection Voltage
Temperature Coefficient
(4)
V
DS
= 0.5V
mA
µA
µs
V
DS
= 5.0V, V
DD
= 5.0V
–
T
A
= -40ºC to +85ºC
±10 ±100 ppm/ºC
(2)
(3)
(4)
Δ −
V
DET
×
1,000,000[ppm /º C]
Δ
T
A
•
- V
DET
Doc. No. 3024 Rev. A
2
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
CAT808
OPERATION – VOLTAGE DETECTOR
The CAT808 has an active low output that asserts
(pulls low) when the supply voltage drops below the
detection threshold voltage (V
DET
). The open-drain
output requires an external pull-up resistor between
the output pin and the supply voltage (as shown in
the typical application diagram). On power-up, ¯¯¯¯
OUT
is held active low until the supply voltage (V
DD
) rises
above V
DET
. While V
DD
is above V
DET
, ¯¯¯¯ stays
OUT
high until V
DD
drops below V
DET
, then ¯¯¯¯ once
OUT
again goes low.
BLOCK DIAGRAM
V
DD
OUT
TIMING DIAGRAM
VOLTAGE
REFERENCE
V
DD
*
V
DET(MAX)
V
DET
V
DET(MIN)
GND
T
PLH
V
OH
T
PHL
V
DET(MAX)
V
DET
V
DET(MIN)
OUT Slews with V
DD
OUT
* Voltage of V
DD
below 1 volt will not be able to maintain low output.
PIN FUNCTIONS
Pin
V
DD
GND
¯¯¯¯
OUT
NC
Function
Voltage Input and Power Supply
Ground Pin
Active Low Open Drain output
No Connect, the pin is electrically open
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
3
Doc. No. 3024 Rev. A
CAT808
TYPICAL ELECTRICAL OPERATING CHARACTERISTICS
Typical values at T
A
= 25°C.
V
DD
Supply Current vs. V
DD
Supply Voltage
5
V
DET
Detection Voltage vs. Temperature
2.71
Supply Current (μA)
4
2.705
2
V
DET
(V)
2.7
2
3
4
5
6
3
1
0
2.695
-40
-5
30
65
100
Supply Voltage (V)
Temperature (ºC)
Response time vs. Load Capacitance
100
I
OUT
Transistor Output Current vs. V
DD
Supply Voltage
10.00
-40ºC
Response time [ms]
10
T
PLH
(mA)
8.00
+25ºC
6.00
+90ºC
1
I
OUT
0.1
4.00
T
PHL
0.01
0.001
0.01
0.000001 0.00001
0.1
0.0001
1
0.001
10
0.01
100
0.1
2.00
0.00
1.00
1.50
2.00
2.50
Load capacitance [nF]
V
DD
(V)
Doc. No. 3024 Rev. A
4
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
CAT808
PACKAGE INFORMATION
5-LEAD TSOT-23 PACKAGE
e
e
E1
E
E1
e1
D
GAUGE
PLANE
L2
b
A1
L
L1
A2
A
c
SYMBOL
A
A1
A2
b
c
D
E
E1
e
e1
L
L1
L2
q
Notes:
MIN
—
0.01
0.80
0.30
0.12
0.30
NOM
—
0.05
0.87
—
0.15
2.90BSC
2.80BSC
1.60BSC
0.95BSC
1.90BSC
0.40
0.60REF
0.25BSC
MAX
1.00
0.10
0.90
0.45
0.20
0.50
0º
8º
(1)
(2)
All dimensions are in millimeters.
Complies with JEDEC specification MO-193.
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
5
Doc. No. 3024 Rev. A
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