HT70XXA-1
TinyPower
TM
Voltage Detector
Selection Table
Part No.
Detectable
Voltage
Hysteresis
Width
Tolerance
Package
Marking
HT7022A-1
2.2V
0.11V
3%
TO-92
SOT-89
SOT-25
70XXA-1 (for TO-92)
70XXA-1 (for SOT-89)
0XXA (for SOT-25)
HT7024A-1
2.4V
0.12V
3%
HT7027A-1
2.7V
0.135V
3%
HT7033A-1
3.3V
0.165V
3%
HT7039A-1
3.9V
0.195V
3%
HT7044A-1
4.4V
0.22V
3%
HT7050A-1
5.0V
0.25V
3%
Note:
XX stands for output voltages.
For lead free devices, TO-92 package will add a
# mark at the end of the date code, whereas SOT-89 &
SOT-25 packages will add a
# mark at the end of the marking.
Rev. 1.40
1
January 26, 2006
General Description
The HT70XXA-1 series devices area set of three terminal
low power voltage detectors implemented in CMOS
technology. Each voltage detector in the series detects a
particular fixed voltage ranging from 2.2V to 5V. The
voltage detectors consist of a high-precision and low
power consumption standard voltage source as well as a
comparator, hysteresis circuit, and an output driver.
CMOS technology ensures low power consumption.
Although designed primarily as fixed voltage detectors,
these devices can be used with external components to
detect user specified threshold voltages.
Features
Low power consumption
Low temperature coefficient
High input voltage range (up to 24V)
Output voltage accuracy: tolerance
3%
Built-in hysteresis characteristic
TO-92, SOT-89 and SOT-25 package
Applications
Battery checkers
Level selectors
Power failure detectors
Microcomputer reset
Battery memory backup
Non-volatile RAM signal storage protectors
Block Diagram
N Channel Open Drain Output (Normal Open; Active Low)
Output Table & Curve
V
DD
V
DD
>V
DET
(+)
V
DD
V
DET
(
-)
V
OUT
Hi-Z
VSS
Pin Assignment
HT70XXA-1
Rev. 1.40
2
January 26, 2006
G N D
V O U T
V D D
V R E F
D a s h l i n e . . . V
I N
f r o m L
O
H
I
S o l i d l i n e . . . V
I N
f r o m H
I
L
O
V
O U T
V
I N
V
H Y S
V
D E T
V
D E T
1 . 0 5
O U T
V D D
V S S
S O T - 8 9
T O - 9 2
O U T V D D V S S
7 0 X X A - 1
F r o n t V i e w
B o t t o m V i e w
S O T - 2 5
N C
N C
T o p V i e w
0 X X A
O U T
V D D
V S S
O U T
V D D
V S S
O U T
V D D
V S S
7 0 X X A - 1
Absolute Maximum Ratings
Supply Voltage .............................................................................................................................V
SS
-0.3V to V
SS
+26V
Output Voltage ...........................V
SS
-0.3V to V
DD
+0.3V
Output Current......................................................50mA
Storage Temperature ............................
-50C to 125C
Power Consumption ..........................................200mW
Operating Temperature ...........................
-40C to 85C
Note: These are stress ratings only. Stresses exceeding the range specified under
Absolute Maximum Ratings may
cause substantial damage to the device. Functional operation of this device at other conditions beyond those
listed in the specification is not implied and prolonged exposure to extreme conditions may affect device
reliability.
Electrical Characteristics
HT7022A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
2.134
2.200
2.266
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
2V
V
OUT
=0.2V
0.5
1
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
1.1
mV/
C
HT7024A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
2.328
2.400
2.472
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
2V
V
OUT
=0.2V
0.5
1
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT70XXA-1
Rev. 1.40
3
January 26, 2006
HT7027A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
2.619
2.700
2.781
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
2V
V
OUT
=0.2V
0.5
1
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT7033A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
3.201
3.300
3.399
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
2.5V
V
OUT
=0.25V
1.2
2.5
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT7039A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
3.783
3.900
4.017
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
2.5V
V
OUT
=0.25V
1.2
2.5
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT70XXA-1
Rev. 1.40
4
January 26, 2006
HT7044A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
4.268
4.400
4.532
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
1.5
24
V
I
OL
Output Sink Current
3.6V
V
OUT
=0.36V
3
6
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT7050A-1
Ta=25
C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
DD
Conditions
V
DET
Detection Voltage
4.850
5.000
5.150
V
V
HYS
Hysteresis Width
0.02
V
DET
0.05
V
DET
0.1
V
DET
V
I
DD
Operating Current
8V
No load
4
7
mA
V
DD
Operating Voltage
2.1
24
V
I
OL
Output Sink Current
3.6V
V
OUT
=0.36V
3
6
mA
D
D
V
T
DET
a
Temperature Coefficient
0
C<Ta<70C
0.9
mV/
C
HT70XXA-1
Rev. 1.40
5
January 26, 2006
Functional Description
The HT70XXA-1 series is a set of voltage detectors
equipped with a high stability voltage reference which is
connected to the negative input of a comparator
denoted as V
REF
in the following figure for NMOS output
voltage detector.
When the voltage drop to the positive input of the
comparator (i,e,V
B
) is higher than V
REF
, VOUT goes
high, M1 turns off, and V
B
is expressed as V
BH
=V
DD
(R
B
+R
C
) / (R
A
+R
B
+R
C
). If V
DD
is decreased so that V
B
falls to a value less than V
REF
, the comparator output
inverts from high to low, V
OUT
goes low, V
C
is high, M1
turns on, RC is bypassed, and V
B
becomes: V
BL
= V
DD
R
B
/ (R
A
+R
B
), which is less than V
BH.
By so doing, the
comparator output will stay low to prevent the circuit
from oscillating when V
B
V
REF
.
If V
DD
falls below the minimum operating voltage, the
output becomes undefined. When VDD goes from low to
V
DD
R
B
/ (R
A
+R
B
) > V
REF
, the comparator output and
V
OUT
goes high.
The detectable voltage is defined as:
V
DET
(
-) =
R + R + R
R + R
A
B
C
B
C
V
REF
The release voltage is defined as:
V
DET
(+) =
R + R
R
A
B
B
V
REF
The hysteresis width is:
V
HYS
= V
DET
(+)
- V
DET
(
-)
The figure demonstrates the NMOS output type with
positive output polarity (V
OUT
is normally open, active
low). The HT70XXA-1 series also supplies options for
other output types with active high outputs. Application
circuits shown are examples of positive output polarity
(normally open, active low) unless otherwise specified.
V
S S
V
D D
R
A
R
B
R
C
M 1
M N
C o m p a r a t o r
V
O U T
R L
V
R E F
V
B
V
C
NMOS Output Voltage Detector (HT70XXA-1)
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