Ultralow Power Voltage Detector
Data Sheet
ADM8641/ADM8642
Rev. C Document Feedback
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FEATURES
Ultralow power consumption with ICC = 92 nA (typical)
Precision, low voltage monitoring
Pretrimmed voltage monitoring threshold options
10 options from 2 V to 4.63 V for the ADM8641
20 options from 0.5 V to 1.9 V for the ADM8642
±1.3% threshold accuracy over full temperature range
Output disable input
23 µs to 26 µs typical propagation delay
Open-drain type output
Power supply glitch immunity
Available in a 1.46 mm × 0.96 mm WLCSP
Operational temperature range: −40°C to +85°C
APPLICATIONS
Portable/battery-operated equipment
Microprocessor systems
Energy metering
Energy harvesting
FUNCTIONAL BLOCK DIAGRAMS
DIS
VCC
GND
V
TH
ADM8641
OUT
12781-001
Figure 1. ADM8641 Functional Block Diagram
DIS
VCC
GND
V
TH
VIN
ADM8642
OUT
12781-002
Figure 2. ADM8642 Functional Block Diagram
GENERAL DESCRIPTION
The ADM8641 and ADM8642 are simple voltage detectors
suitable for use in general-purpose applications. The ultralow
power consumption of these devices makes them suitable for
power efficiency sensitive systems, such as battery-powered
portable devices and energy meters.
The factory preset detection thresholds from 0.5 V to 4.63 V
with ±1.2% accuracy over the full temperature range enable the
devices to monitor the node of interest accurately with direct
contact. The DIS input lets the user hold the output low
regardless of the state of the input. Not all device options are
released for sale as standard models. See the Ordering Guide
section for full information.
The ADM8641 monitors the voltage using the VCC pin. The
separate supply pin on the ADM8642 allows it to have a lower
detection threshold down to 0.5 V.
The ADM8641 and ADM8642 are available in a 6-ball, 1.46 mm ×
0.96 mm WLCSP. These devices are specified over the −40°C to
+85°C temperature range.
ADM8641/ADM8642 Data Sheet
Rev. C | Page 2 of 11
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagrams ............................................................. 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution .................................................................................. 5
Pin Configurations and Function Descriptions ........................... 6
Typical Performance Characteristics ..............................................7
Theory of Operation .........................................................................9
Voltage Monitoring Input ............................................................9
VIN as an Adjustable Input ..........................................................9
Transient Immunity ......................................................................9
Output .............................................................................................9
Disable Input ..................................................................................9
Device Model Options ................................................................... 10
Outline Dimensions ....................................................................... 11
Ordering Guide .......................................................................... 11
REVISION HISTORY
1/2018—Rev. B to Rev. C
Changes to General Description .................................................... 1
Added Note 1 to Tabl e 1 .................................................................. 3
Changed Out Output Parameter, Table 1 to Out Pin Output
Parameter, Table 1, DIS Input Parameter, Table 1 to DIS Pin Input
Parameter, Table 1 ............................................................................. 4
Changed Device Options Section to Device Model Options
Section .............................................................................................. 10
Changes to Device Model Options Section ................................ 10
Changes to Ordering Guide .......................................................... 11
1/2016—Rev. A to Rev. B
Changes to Ordering Guide .......................................................... 11
4/2015—Rev. 0 to Rev. A
Changes to Threshold Hysteresis Parameter, Table 1 ................... 3
1/2015—Revision 0: Initial Version
Data Sheet ADM8641/ADM8642
Rev. C | Page 3 of 11
SPECIFICATIONS
VCC = 2 V to 5.5 V, V IN < VCC + 0.3 V, TA = −40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C.
Table 1.
Parameter Symbol Min Typ Max Unit Test Conditions/Comments
OPERATING VOLTAGE RANGE VCC
ADM8641
0.9
5.5
V
Guarantees valid OUT output
ADM8642 2 5.5 V Guarantees valid OUT output
0.9 V Guarantees OUT low
UNDERVOLTAGE LOCKOUT ADM8642 only
Input Voltage Rising UVLORISE 1.95 V
Input Voltage Falling UVLOFALL 1.6 V
Hysteresis UVLOHYS 90 mV
INPUT CURRENT
VCC Quiescent Current ICC 92 190 nA VCC = 2 V to 5.5 V, OUT pulled high
110 nA TA = 25°C, OUT pulled high
VIN Average Input Current IVIN 4 32 nA VIN = 2 V, VCC = 2 V
4
8.5
nA
V
IN
= 2 V, V
CC
= 5.5 V
THRESHOLD VOLTAGE1 VTH Input falling
ADM8641 VTH − 1.3% VTH VTH + 1.3% V See Table 6
ADM8642 VTH − 1.3% VTH VTH + 1.3% V See Table 7, VTH ≥ 1.2 V
VTH − 1.4% 1.1 VTH + 1.4% V 1.1 V threshold option
VTH − 1.6% 1 VTH + 1.6% V 1 V threshold option
VTH − 1.6% 0.95 VTH + 1.6% V 0.95 V threshold option
VTH − 1.7% 0.9 VTH + 1.7% V 0.9 V threshold option
V
TH
− 1.8%
0.85
V
TH
+ 1.8%
V
0.85 V threshold option
VTH − 1.8% 0.8 VTH + 1.8% V 0.8 V threshold option
VTH − 1.9% 0.75 VTH + 1.9% V 0.75 V threshold option
VTH − 1.9% 0.7 VTH + 1.9% V 0.7 V threshold option
VTH − 2.0% 0.65 VTH + 2.0% V 0.65 V threshold option
VTH − 2.1% 0.6 VTH + 2.1% V 0.6 V threshold option
V
TH
− 2.1%
0.55
V
TH
+ 2.1%
V
0.55 V threshold option
VTH − 2.2% 0.5 VTH + 2.2% V 0.5 V threshold option
THRESHOLD HYSTERESIS VHYST
ADM8641 0.9% × VTH V
ADM8642 0.9% × VTH V VTH > 1 V
10.3 mV VTH ≤ 1 V
PROPAGATION DELAY
ADM8641 VCC to OUT tPD_VCC 18 26 37 µs VCC falling with VTH × 10% overdrive
20.5 36 57 µs VCC rising with VTH × 10% overdrive
ADM8642 VIN to OUT tPD_VIN 13.5 23 35 µs VIN falling with VTH × 10% overdrive
22 39.5 61 µs VIN rising with VTH × 10% overdrive
INPUT GLITCH REJECTION
ADM8641 VCC Glitch Rejection tGR_VCC 23 µs VCC falling with VTH × 10% overdrive
35 µs VCC rising with VTH × 10% overdrive
ADM8642 VIN Glitch Rejection tGR_VIN 21 µs VIN falling with VTH × 10% overdrive
38 µs VIN rising with VTH × 10% overdrive
ADM8641/ADM8642 Data Sheet
Rev. C | Page 4 of 11
Parameter Symbol Min Typ Max Unit Test Conditions/Comments
OUT PIN OUTPUT
Output Voltage Low VOUT_OL 0.4 V VCC > 4.25 V, ISINK = 6.5 mA
0.4 V VCC > 2.5 V, ISINK = 6 mA
0.4 V VCC > 1.2 V, ISINK = 4.6 mA
0.4
V
V
CC
> 0.9 V, I
SINK
= 0.9 mA
Leakage Current 5 nA VOUT = VCC = 5.5 V
DIS PIN INPUT
V
IL
0.4
V
VIH 0.9 V
DIS Glitch Rejection 0.4 µs
DIS to OUT Delay tD_DIS1 0.65 µs DIS falling
DIS Pull-Up Resistance 0.5 0.6 0.82 MΩ
1 Not all device options are released for sale as standard models. See the Ordering Guide section for full information.
Data Sheet ADM8641/ADM8642
Rev. C | Page 5 of 11
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
VCC −0.3 V to +6 V
OUT
−0.3 V to +6 V
VIN −0.3 V to +6 V
DIS −0.3 V to VCC + 0.3 V
Input/Output Current 10 mA
Storage Temperature Range −40°C to +150°C
Operating Temperature Range −40°C to +85°C
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
THERMAL RESISTANCE
θJA is specified for a device soldered on an FR4 board with a
minimum footprint.
Table 3.
Package Type θJA Unit
6-Ball WLCSP 105.6 °C/W
ESD CAUTION
ADM8641/ADM8642 Data Sheet
Rev. C | Page 6 of 11
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
DNC = DO NO CO NNE CT.
DO NO T CO NNE CT TO THIS PIN.
VCC GND
DIS
DNC
OUT
TOP VIEW
(BALL SIDE DOWN)
Not t o Scal e
1
A
B
C
2
BALLA1
INDICATOR
GND
12781-003
Figure 3. ADM8641 Pin Configuration
Table 4. ADM8641 Pin Function Descriptions
Pin No. Mnemonic Description
A1 VCC Power Supply Input. The voltage on the VCC pin is monitored on the ADM8641. It is recommended to
place a 0.1 µF decoupling capacitor between the VCC pin and the GND pin.
A2 GND Ground. Both GND pins on the ADM8641 must be grounded.
B1 DNC Do Not Connect. Do not connect to this pin.
B2 GND Ground. Both GND pins on the ADM8641 must be grounded.
C1 DIS Active Low Output Disable Input.
C2 OUT Open-Drain Detector Output.
VCC GND
DIS
VIN OUT
TOP VIEW
(BALL SIDE DOWN)
Not t o Scal e
1
A
B
C
2
BALLA1
INDICATOR
GND
12781-004
Figure 4. ADM8642 Pin Configuration
Table 5. ADM8642 Pin Function Descriptions
Pin No. Mnemonic Description
A1 VCC Power Supply Input. The voltage on the VCC pin is not monitored on the ADM8642. It is recommended to
place a 0.1 µF decoupling capacitor between the VCC pin and the GND pin.
A2 GND Ground. Both GND pins on the ADM8642 must be grounded.
B1 DIS Active Low Output Disable Input.
B2 GND Ground. Both GND pins on the ADM8642 must be grounded.
C1 VIN Low Voltage Monitoring Input. This separate supply input allows the ADM8642 to monitor low voltages of
0.8 V on the VIN pin.
C2 OUT Open-Drain Detector Output.
Data Sheet ADM8641/ADM8642
Rev. C | Page 7 of 11
TYPICAL PERFORMANCE CHARACTERISTICS
70
75
80
85
90
95
100
105
110
115
120
–40 –30 –20 –10 010 20 30 40 50 60 70 80
ICC ( nA)
TEMPERATURE (
°C)
12781-005
Figure 5. Supply Current (ICC) vs. Temperature
0
0.5
1.0
1.5
2.0
2.5
3.0
00.5 1.0 1.5 2.0 2.5
I
CC
(µA)
SUPPLY VOLTAGE (V)
V
CC
FALLING
V
CC
RISING
12781-006
Figure 6. Supply Current (ICC) vs. Supply Voltage, VCC < 2 V
60
70
80
90
100
110
120
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
I
CC
(n A)
SUPPLY VOLTAGE (V)
12781-007
Figure 7. Supply Current (ICC) vs. Supply Voltage
–2
–1
0
1
2
3
4
5
6
7
8
00.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
INP UT CURRENT ( µA)
V
IN
(V)
I
VIN
, V
CC
= 0V
I
VIN
, V
CC
= 2V
I
CC
, V
CC
= 2V
12781-008
Figure 8. VIN Pin and VCC Pin Input Current vs. VIN
0.980
0.985
0.990
0.995
1.000
1.005
1.010
1.015
1.020
–40 –20 020 40 60 80
NORMALIZED FALLING THRESHOLD
TEMPERATURE ( °C)
V
TH
= 0.6V
V
TH
= 2.0V
V
TH
= 3.3V
V
TH
= 4.7V
12781-115
Figure 9. Normalized Falling Threshold vs. Temperature
0
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
00.5 1.0 1.5 2.0 2.5 3.0
OUT PIN VOLTAGE (V)
VOLTAGE ON VCC (V )
R
PULLUP
= 10kΩ
R
PULLUP
= 100kΩ
12781-010
Figure 10. OUT Pin Voltage vs. Voltage on VCC
(with the OUT Pin Pulled up to the VCC Pin Through RPULLUP)
ADM8641/ADM8642 Data Sheet
Rev. C | Page 8 of 11
12781-011
0
50
100
150
200
250
300
350
400
450
110100
TRANSIENT DUR
A
TION (µs)
INPUT OVERDRIVE (mV)
V
IN
FALLING
V
IN
RISING
Figure 11. Maximum Transient Duration vs. Input Overdrive
0
1
2
3
4
5
6
7
8
–40–30–20–100 1020304050607080
VIN PIN LEAKAGE CURRENT (nA)
TEMPERATURE (°C)
VCC = 5.5V
VCC = 3.3V
VCC = 2V
12781-114
Figure 12. VIN Pin Leakage Current vs. Temperature
–0.20
–0.15
–0.10
–0.05
0
0.05
0.10
0.15
0.20
0.25
0.30
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
OUPUT LEAKAGE CURRENT (nA)
OUTPUT VOLTAGE (V)
12781-013
Figure 13. Output Leakage Current vs. Output Voltage
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
1234567891011121314151617181920
OUT LOW LEVEL OUTPUT VOL
T
AGE (V)
I
SINK
(mA)
V
CC
= 0.9V
V
CC
= 1.2V
V
CC
= 2.5V
V
CC
= 4.25V
12781-014
Figure 14. OUT Low Level Output Voltage vs. Sink Current (ISINK)
12781-015
Figure 15. OUT Propagation Delay With VCC/VIN Rising
12781-016
Figure 16. OUT Propagation Delay With VCC/VIN Falling
Data Sheet ADM8641/ADM8642
Rev. C | Page 9 of 11
THEORY OF OPERATION
The ADM8641 and ADM8642 ultralow power voltage detectors
are especially suited for battery-powered applications due to the
190 nA quiescent current (maximum). The internal precision
reference allows the user to monitor specific voltage levels accur-
ately from 0.5 V to 4.63 V. These devices feature internal input
hysteresis and an open-drain output. The output remains logic
high after the monitored input is above the preset threshold. The
output changes to logic low after the input voltage falls below
the threshold. The devices keep the output in a logic low state
whenever the supply voltage on the VCC pin is below the
UVLO threshold. The output disable input can also keep the
output low regardless of the status on the input.
ADM8641
MICRO-
PROCESSOR
VCC OUT INPUT
GND
DIS
3.3V
VIO
12781-117
Figure 17. ADM8641 Typical Application Circuit
ADM8642
MICRO-
PROCESSOR
VCC
VIN
OUT
GND
12V 3.3V
INPUT
VIO
DIS
12781-118
Figure 18. ADM8642 Typical Application Circuit
VOLTAGE MONITORING INPUT
The VCC pin on the ADM8641 acts as both a device power
input node and a voltage monitoring input node. The ADM8642
uses separate pins for supply and voltage monitoring to achieve
a low voltage monitoring threshold to 0.5 V. It is recommended
to place a 0.1 µF decoupling capacitor between the VCC pin and
the GND pin.
VIN AS AN ADJUSTABLE INPUT
Due to the low leakage nature of the VIN pin, the ADM8642 can be
used as a device with an adjustable threshold. Use an external
resistor divider circuit to program the desired voltage monitoring
threshold based on the VIN threshold, as shown in Figure 19.
ADM8642 MICRO-
PROCESSOR
VCC
VIN
OUT
GND
0.8V
3.3V
INPUT
VIO
DIS
12781-119
Figure 19. ADM8642 as an Adjustable Threshold Device
TRANSIENT IMMUNITY
To avoid unnecessary output state changes caused by fast power
supply transients, an input glitch filter is added to the VCC pin
of the ADM8641 and the VIN pin of the ADM8642 to filter out
the transient glitches on these pins.
Figure 11 shows the comparator overdrive (that is, the maximum
magnitude of positive and negative going pulses with respect to
the typical threshold) vs. the pulse duration without changing
the state of the output.
OUTPUT
Both the ADM8641 and ADM8642 voltage detectors have an
open-drain output. For the ADM8641, the state of the output is
guaranteed to be valid as soon as VCC rises above 0.9 V. For the
ADM8642, the output is guaranteed to be logic low from when
VCC = 0.9 V to when the device exits ULVO.
When the monitored voltage falls below its associated threshold,
the OUT pin asserts low after 23 µs to 26 µs (typical). When the
monitored voltage rises above the threshold plus hysteresis, the
OUT pin asserts high after 36 µs to 39.5 µs (typical).
DISABLE INPUT
The ADM8641/ADM8642 feature a disable input (DIS). Drive the
DIS pin low to assert the output low. The DIS input has a 0.6 MΩ
internal pull-up resistor so that the input is always high when
unconnected. To drive the DIS input, use an external signal or
a push-button switch to ground; debounce circuitry is integrated
on-chip for this purpose. Noise immunity is provided on the
DIS input, and fast, negative going transients of up to 0.4 µs
(typical) are ignored. If required, a 0.1 μF capacitor between
the DIS pin and ground provides additional noise immunity.
VCC
OUT
VTH
VTH + VHYST
tPD_VCC
DIS EXT E RNALLY
DRIVE N LO W
DIS
tPD_VCC
tD_DIS tD_DIS
12781-017
Figure 20. DIS Input Timing
ADM8641/ADM8642 Data Sheet
Rev. C | Page 10 of 11
DEVICE MODEL OPTIONS
The ADM8641/ADM8642 include many device options,
however, not all options are released for sale. Released options
are called standard models and are listed in the Ordering Guide
section. The Simple Reset Supervisory IC page also offers a list
of standard models. Contact a sales representative for information
on nonstandard models and be aware that samples and
production units have long lead times.
Table 6. ADM8641 VCC Threshold (VTH) Options (TA = −40°C to +85°C)
Threshold Number Min Typ Max Unit
200 1.974 2 2.026 V
220 2.171 2.2 2.229 V
232 2.290 2.32 2.350 V
263 2.596 2.63 2.664 V
280
2.764
2.8
2.836
V
293 2.892 2.93 2.968 V
300 2.961 3 3.039 V
308 3.040 3.08 3.120 V
440 4.343 4.4 4.457 V
463 4.570 4.63 4.690 V
Table 7. ADM8642 VIN Threshold (VTH) Options (TA = −40°C to +85°C)
Threshold Number Min Typ Max Unit
050
0.489
0.5
0.511
V
055 0.538 0.55 0.562 V
060 0.588 0.6 0.612 V
065 0.637 0.65 0.663 V
070 0.686 0.7 0.714 V
075 0.736 0.75 0.764 V
080 0.785 0.8 0.815 V
085 0.835 0.85 0.865 V
090 0.885 0.9 0.915 V
095 0.935 0.95 0.965 V
100 0.984 1 1.016 V
110
1.084
1.1
1.116
V
120 1.184 1.2 1.216 V
130 1.283 1.3 1.317 V
140 1.382 1.4 1.418 V
150 1.481 1.5 1.520 V
160 1.579 1.6 1.621 V
170 1.678 1.7 1.722 V
180 1.777 1.8 1.823 V
190 1.875 1.9 1.925 V
ADM864_ T_ _ _ACBZ-R7
GENE RIC NUMBE R
(1 O R 2)
THRE SHOL D NUM BE R
(050 T O 463)
TE M P ERATURE RANGE
A: –40° C TO + 85°C PACKAGE DE S IG NATION
CB: W LCSP
Z = LEAD- FREE
PACKING MATERI AL
R7 = 7" TAP E AND RE E L
(3000 PIECE QUANTIT Y )
12781-018
Figure 21. Ordering Code Structure
Data Sheet ADM8641/ADM8642
Rev. C | Page 11 of 11
OUTLINE DIMENSIONS
08-25-2014-A
A
B
C
0.660
0.600
0.540
0.390
0.360
0.330
0.270
0.240
0.210
1.000
0.960
0.920
1.500
1.460
1.420
1
2
BOTTOM VI EW
(BALL SIDE UP)
TOP VIEW
(BALL SI DE DOW N)
SIDE VIEW
0.360
0.320
0.280
1.00
REF
0.50
BSC
BALLA1
IDENTIFIER
SEATING
PLANE
0.50 BSC
COPLANARITY
0.04
PKG-003299
Figure 22. 6-Ball Wafer Level Chip Scale Package [WLCSP]
(CB-6-17)
Dimensions shown in millimeters
ORDERING GUIDE
Model1, 2, 3 Temperature Range Threshold Voltage (V) Package Description Package Option Marking Code
ADM8641T263ACBZ-R7 −40°C to +85°C 2.63 6-Ball WLCSP CB-6-17 DT
ADM8642T100ACBZ-R7 −40°C to +85°C 1.0 6-Ball WLCSP CB-6-17 DU
ADM8641-EVALZ Evaluation Board
ADM8642-EVALZ Evaluation Board
1 Z = RoHS Compliant Part.
2 ADM8641/ADM8642 include many device options, however, not all options are released for sale. Released options are called standard models and are listed in the
Ordering Guide. The Simple Reset Supervisory IC page also offers a list of standard models. Contact a sales representative for information on nonstandard models and
be aware that samples and production units have long lead times.
3 If ordering nonstandard models, complete the ordering code shown in Figure 21 by inserting the model number and threshold number.
©2015–2018 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D12781-0-1/18(C)
