MIC841/2
Micrel
MIC841/842
Comparator with Reference
General Description
The MIC841 and MIC842 are micropower, precision voltage
comparators with an on-chip voltage reference.
Both devices are intended for voltage monitoring applications.
External resistors are used to set the voltage monitor threshold.
When the threshold is crossed, the outputs switch polarity.
The MIC842 incorporates a voltage reference and comparator
with fixed internal hysteresis; two external resistors are used to
set the switching threshold voltage. The MIC841 provides a
similar function with user adjustable hysteresis; this part re-
quires three external resistors to set the upper and lower
thresholds (the difference between the threshold voltages
being the hysteresis voltage).
Both the MIC841 and MIC842 are available with push-pull or
open-drain output stage. The push-pull output stage is config-
ured either active high or active low; the open-drain output stage
is only configured active high.
Supply current is extremely low (1.5µA, typical), making it ideal
for portable applications.
The MIC841/2 is supplied in Micrel’s Teeny™ 5-lead SC-70
package.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Teeny™
Features
• Optimized for PDAs, cellular telephones, pagers,
and other battery-powered devices
• Output can be pulled up to 6V regardless of supply
voltage (841NBC5 only)
• High
±1.25%
voltage threshold accuracy
• Built in hysteresis for noise suppression
(MIC842)
• Extremely low 1.5µA typical supply current
• Immune to brief input transients
• Teeny™ 5-lead SC-70 package
Applications
•
•
•
•
•
•
PDAs
Pagers
Cordless phones
Consumer electronics
Embedded controllers
Personal electronics
Typical Application
V
IN
V
DD
MIC841
R1
5
3
V
IN
V
DD
4
VDD
LTH
HTH
OUT
GND
V
OUT
V
LTH
> V
HTH
V
REF
= 1.24V
1.5V
≤
V
DD
≤
5.5V
MIC842
R1
5
R2
1
2
VDD
INP
OUT
GND
4
V
OUT
V
REF
= 1.24V
1.5V
≤
V
DD
≤
5.5V
1
2
R3
R2
Threshold Detection with Hysteresis Set by a Third
External Resistor
Threshold Detector with Internal Fixed Hysteresis
Teeny™ is a trademark of Micrel, Inc.
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
January 2005
1
MIC841/2
MIC841/2
Micrel
Ordering Information
Part Number
MIC841HBC5
MIC841LBC5
MIC841NBC5
MIC842HBC5
MIC842LBC5
MIC842NBC5
MIC841HYC5
MIC841LYC5
MIC841NYC5
MIC842HYC5
MIC842LYC5
MIC842NYC5
Marking
B13
B14
B15
B16
B17
B18
B13
B14
B15
B16
B17
B18
Hysteresis
Adjustment
External
External
External
Internal
Internal
Internal
External
External
External
Internal
Internal
Internal
Output
Stage
Push Pull
Push Pull
Open Drain
Push Pull
Push Pull
Open Drain
Push Pull
Push Pull
Open Drain
Push Pull
Push Pull
Open Drain
Output
Function
Active High
Active Low
Active High
Active High
Active Low
Active High
Active High
Active Low
Active High
Active High
Active Low
Active High
Temp. Range
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
Pb-Free
Package
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
SC-70-5
MIC841/2
2
January 2005
MIC841/2
Micrel
Pin Configuration
LTH GND HTH
3
2
1
NC GND INP
3
2
1
Bxx
4
5
4
Bxx
5
OUT
VDD
OUT
VDD
MIC841
SC-70-5 (C5)
MIC842
SC-70-5 (C5)
Pin Description MIC841
Pin Number
1
Pin Name
HTH
Pin Function
High-Voltage Threshold (Input): Analog input to a comparator. This is the
voltage input assigned to detect a high-voltage condition. When the level on
this pin exceeds V
REF
, OUT is asserted and the condition is latched until
V
LTH
< V
REF
.
Ground.
Low-Voltage Threshold (Input): Analog input to a comparator. This is the
voltage input assigned to detect a low voltage condition. When the level on
this pin falls below V
REF
, OUT is de-asserted and the condition is latched
until V
HTH
> V
REF
.
Output: Active-high, open-drain output. This output is de-asserted and
latched when V
LTH
<V
REF
, indicating a low voltage condition. This state
remains latched until V
HTH
> V
REF
.
Output: Push-pull output. This output is de-asserted and latched when V
LTH
< V
REF
, indicating a low voltage condition. This state remains latched until
V
HTH
> V
REF
.
Output: Push-pull output. This output is asserted and latched when
V
LTH
< V
REF
, indicating a low voltage condition. This state remains latched
until V
HTH
> V
REF
.
Power Supply (Input): Independent supply input for internal circuitry.
2
3
GND
LTH
4
OUT (“N” Version)
OUT (“H” Version)
OUT (“L” Version)
5
V
DD
Pin Description MIC842
Pin Number
1
2
3
4
Pin Name
INP
GND
NC
OUT (“N” Version)
Pin Function
Input: Analog input to the comparator. When V
INP
> V
REF
+ V
HYST
, V
OUT
is
asserted, and the condition is held until V
INP
< V
REF
.
Ground.
No Connect.
Output: Active-high, open-drain output. This output is de-asserted when
V
INP
< V
REF
, indicating a low voltage input. The output is asserted when
V
INP
> V
REF
+ V
HYST
.
Output: Push-pull output. This output is de-asserted and latched when
V
INP
< V
REF
, indicating a low voltage condition. This state remains latched
until V
INP
> V
REF
+ V
HYST
.
Output: Push-pull output. This output is asserted and latched when
V
INP
< V
REF
, indicating a low voltage condition. This state remains latched
until V
INP
> V
REF
+ V
HYST
.
Power Supply (Input): Independent supply input for internal circuitry.
OUT (“H” Version)
OUT (“L” Version)
5
V
DD
January 2005
3
MIC841/2
MIC841/2
Micrel
Absolute Maximum Ratings
(1)
Supply Voltage (V
DD
) ..................................... –0.3V to +7V
Input Voltage (V
INP
) ...................................................... +7V
Output Current (I
OUT
) ................................................. 20mA
Storage Temperature (T
S
) ....................... –65°C to +150°C
ESD Rating,
Note 3
...................................................... 1kV
Operating Ratings
(2)
Supply Voltage (V
DD
) .................................. +1.5V to +5.5V
Input Voltage (V
INP
) ......................................... –0.3V to 6V
Ambient Temperature Range (T
A
) ............. –40°C to +85°C
Junction Temperature (T
J
) ....................... Internally Limited
Package Thermal Resistance (θ
JA
) ...................... 450°C/W
Electrical Characteristics
(4)
1.5V
≤
V
DD
≤
5.5V; T
A
= +25°C,
bold
values indicate –40°C
≤
T
A
≤
+85°C; unless noted.
Symbol
I
DD
I
INP
V
REF
V
HYST
t
D
V
OUT
(Note
6)
Output Voltage-High
Parameter
Supply Current
Input Leakage Current
Reference Voltage
0°C to 85°C
–40°C to 85°C
Hysteresis Voltage, (Note
5)
Propagation Delay
MIC842 only
V
INP
= 1.352V to 1.128V
V
INP
= 1.143V to 1.367V
Output Voltage-Low
I
SINK
= 1.6mA, V
DD
≥
1.6V
I
SINK
= 100µA, V
DD
≥
1.2V
I
SOURCE
= 500µA, V
DD
≥
1.6V
I
SOURCE
= 50µA, V
DD
≥
1.2V
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
4. Specification for packaged product only.
5. V
HTH
= V
REF
+ V
HYST
.
6. V
DD
operating range is 1.5V to 5.5V. Output is guaranteed to be de-asserted down to V
DD
= 1.2V.
Condition
output not asserted
Min
Typ
1.5
0.005
Max
3
10
1.256
1.261
35
Units
µA
nA
V
V
mV
µs
µs
1.225
1.219
8
1.240
1.240
20
12
8
0.05
0.005
0.99V
DD
0.99V
DD
0.3
0.4
V
V
V
V
MIC841/2
4
January 2005
MIC841/2
Micrel
Block Diagrams
V
DD
5
V
IN
V
DD
5
V
DD
V
IN
Low-Voltage
Detect
V
DD
INP
LTH
V
LTH
3
High-Voltage
Detect
OUT
4
V
TH
R Q
High-Voltage
Detect
4
1
OUT
HTH
V
HTH
1
S Q
1.24V
Bandgap
Reference
1.24V
Bandgap
Reference
MIC841H
2
MIC842H
2
GND
GND
V
DD
5
V
IN
Low-Voltage
Detect
LTH
V
LTH
3
V
DD
V
IN
V
DD
5
V
DD
INP
R Q
High-Voltage
Detect
4
High-Voltage
Detect
OUT
4
OUT
V
TH
1
HTH
V
HTH
1
S Q
1.24V
Bandgap
Reference
1.24V
Bandgap
Reference
MIC841L
2
MIC842L
2
GND
GND
V
DD
5
V
IN
Low-Voltage
Detect
LTH
V
LTH
3
V
DD
V
IN
V
DD
5
V
DD
INP
R Q
High-Voltage
Detect
S Q
4
High-Voltage
Detect
OUT
4
OUT
V
TH
1
HTH
V
HTH
1
1.24V
Bandgap
Reference
1.24V
Bandgap
Reference
MIC841N
2
MIC842N
2
GND
GND
January 2005
5
MIC841/2
京公网安备 11010802033920号
EEWORLD
