M
FEATURES
MCP100/101
PACKAGES
Microcontroller Supervisory Circuit with Push-Pull Output
• Holds microcontroller in reset until supply voltage
reaches stable operating level
• Resets microcontroller during power loss
• Precision monitoring of 3V, 3.3V, and 5V systems
• 7 voltage trip points available
• Active low RESET pin (MCP100) or active high
RESET (MCP101)
• Push-pull output
• Holds RESET/RESET for 350 ms (typical)
• Guaranteed RESET/RESET to V
DD
= 1.0V
• Accuracy of ±125mV for 5V systems and ±75mV
for 3V systems over temperature
• 45 µA typical operating current
• Temperature range:
- Industrial (I): -40°C to +85°C
TO-92 with
‘D’ Bondout
TO-92 with
‘H’ Bondout
RST
OR
RST
V
DD
V
SS
V
DD
RST
OR
V
SS
RST
MCP100
MCP101
MCP100
MCP101
SOT-23-3
RST
OR
DESCRIPTION
The Microchip Technology Inc. MCP100/101 is a volt-
age supervisory device designed to keep a microcon-
troller in reset until the system voltage has reached the
proper level and stabilized. It also operates as protec-
tion from brown-out conditions when the supply voltage
drops below a safe operating level. Both devices are
available with a choice of seven different trip voltages
and both have push-pull outputs. The MCP100 has a
low active RESET pin and the MCP101 has a high
active RESET pin. The MCP100/101 will assert the
RESET/RESET signal whenever the voltage on the
V
DD
pin is below the trip-point voltage.
RST
V
DD
MCP100
MCP101
V
SS
BLOCK DIAGRAM
V
DD
Comparator
+
-
Delay
Circuit
Output
Driver
RESET
or
RESET
Bandgap
Reference
©
1999 Microchip Technology Inc.
Preliminary
DS11187C-page 1
MCP100/101
1.0
1.1
ELECTRICAL CHARACTERISTICS
Maximum Ratings*
*Notice:
Stresses above those listed under “Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and functional operation of
the device at those or any other conditions above those
indicated in the operational listings of this specification
is not implied. Exposure to maximum rating conditions
for extended periods may affect device reliability.
V
DD
..................................................................................7.0V
All inputs and outputs w.r.t. V
SS
............... -0.6V to V
DD
+1.0V
Storage temperature ..................................... -65˚C to +150˚C
Ambient temp. with power applied................. -65˚C to +125˚C
Soldering temperature of leads (10 seconds) ............. +300˚C
ESD protection on all pins
..................................................≥
2 kV
DC AND AC CHARACTERISTICS
All parameters apply at the specified
temp and voltage ranges unless oth-
erwise noted.
PARAMETER
Operating Voltage Range
V
DD
Value to Guarantee RESET/
RESET
Operating current
MCP10X-270
MCP10X-300
MCP10X-315
MCP10X-450
MCP10X-460
MCP10X-475
MCP10X-485
MCP100-270
MCP100-300
MCP100-315
MCP100-450
MCP100-460
MCP100-475
MCP100-485
V
OL
V
DD
= 1.0 - 5.5V
Industrial (I):-40°C to +85°C
SYMBOL
V
DD
V
DD
MIN
I
DD
2.55
2.85
3.0
4.25
4.35
4.50
4.60
MIN
1.0
1.0
45
2.625
2.925
3.075
4.375
4.475
4.625
4.725
60
2.7
3.0
3.15
4.50
4.60
4.75
4.85
0.4
TYP
MAX
5.5
UNITS
V
V
µA
V
V
DD
= 5.5V (no load)
TEST CONDITIONS
V
DD
Trip Point
V
TRIP
V
I
OL
= 3.2mA, V
DD
= V
TRIP
MIN
RESET Low Level
Output Voltage
(MCP100)
0.6
I
OL
= 8.5mA, V
DD
= V
TRIP
MIN
RESET High Level
MCP100-XXX
Output Voltage
(All V
TRIP
Points)
(MCP100)
MCP101-270
MCP101-300
MCP101-315
MCP101-450
MCP101-460
MCP101-475
MCP101-485
MCP101-XXX
(All V
TRIP
Points)
V
DD
-0.7
V
OH
0.4
V
I
OH
= 3mA,V
DD
> V
TRIP
MAX
V
I
OL
= 3.2mA, V
DD
> V
TRIP
MAX
RESET Low Level
Output Voltage
(MCP101)
V
OL
0.6
I
OL
= 8.5mA, V
DD
> V
TRIP
MAX
RESET High level
Output Voltage
(MCP101)
V
DD
-0.7
V
OH
V
HYS
t
RPU
t
RPD
150
50
350
10
700
V
I
OH
= 3mA,V
DD
= V
TRIP
MIN
Threshold Hysteresis
V
DD
Detect to RESET/RESET Inactive
V
DD
Detect to RESET/RESET
mV
ms
µs
V
DD
ramped from V
TRIP
MAX
+
250mV down to V
TRIP
MIN
-
250mV
DS11187C-page 2
Preliminary
©
1999 Microchip Technology Inc.
MCP100/101
V
TRIP
V
DD
t
RPU
t
RPD
RESET
(MCP100)
V
OH
V
OL
RESET
(MCP101)
V
OL
FIGURE 1-1:
MCP100/101 Timing Diagram
2.0
2.1
APPLICATIONS INFORMATION
The Need for Supervisory Circuits
5V
SUPPLY VOLTAGE
V
TRIP
MAX
V
TRIP
MIN
(V
TRIP
MIN
-
V
DD
)
T
RANSIENT
D
URATION
For many of today’s microcontroller applications, care
must be taken to prevent low power conditions that can
cause many different system problems. The most com-
mon causes are brown-out conditions where the sys-
tem supply drops below the operating level
momentarily, and the second, is when a slowly decay-
ing power supply causes the microcontroller to begin
executing instructions without enough voltage to sus-
tain SRAM and producing indeterminate results.
V
DD
MICROCONTROLLER
bypass
capacitor
0
0
TIME
V
DD
10
T
A
= +25°C
TRANSIENT DURATION (µS)
MCP100
V
SS
V
DD
RST
MCLR
OR
RESET
8
6
Transients above the
curve will cause a reset
4
VSS
2
Transients below
the curve will NOT
cause a reset
0
0
1
2
3
4
5
V
TRIP
- V
DD
(V)
FIGURE 2-1:
Typical Application
2.2
Negative Going V
DD
Transients
Many system designers implementing POR circuits are
concerned about the minimum pulse width required to
cause a reset. Figure 2-2 shows typical transient dura-
tion vs. reset comparator overdrive for which the
MCP100/101 will not generate a reset pulse. It shows
that the farther below the trip point the transient pulse
goes, the duration of the pulse required to cause a
reset gets shorter. A 0.1 µF bypass cap mounted as
close as possible to the V
DD
pin provides additional
transient immunity.
FIGURE 2-2:
Typical Transient Response
©
1999 Microchip Technology Inc.
Preliminary
DS11187C-page 3
MCP100/101
2.3
NORMALIZED THRESHOLD* (V
TRIP
)
Effect of Temperature on Timeout
Period (t
RPU
)
1.002
The timeout period (t
RPU
) determines how long the
device remains in the reset condition. This is controlled
by an internal RC timer and is effected by both V
DD
and
temperature. The graph shown in Figure 2-3 shows
typical response for different V
DD
values and tempera-
tures.
1.000
0.998
0.996
0.994
700
0.992
TIMEOUT PERIOD (T
RPU
) (MS)
600
V
DD
= 6V
500
V
DD
= 5V
400
0.997
-40
-20
0
20
40
60
80
100
TEMPERATURE (˚C)
* Multiply value at 25˚C by this factor to
determine the value at temperature
300
V
DD
= 4V
200
V
DD
= 3V
FIGURE 2-5:
Normalized V
TRIP
vs. Temperature
800
100
-40
V
DD
= 2.5V
-20
0
20
40
60
80
100
700
V
DD
= 1.5V
600
V
OL
(mV)
V
DD
= 3.5V
TEMPERATURE (˚C)
FIGURE 2-3:
Typical t
RPU
vs. Temperature
500
400
300
V
DD
= 4.5V
60
V
DD
= 5V
V
DD
= 5.5V
200
100
T
A
= +25°C
0
0
2
4
6
8
10
12
14
16
18
20
50
Operating Current (µA)
40
I
OL
(mA)
30
V
DD
= 4V
20
V
DD
= 3V
FIGURE 2-6:
V
OL
vs. I
OL
10
1.3
0
-40
-20
0
20
40
60
80
100
1.2
TEMPERATURE (˚C)
1.1
NORMALIZED I
OL
*
FIGURE 2-4:
I
DD
vs. Temperature
1.00
0.9
0.8
0.7
-40
-20
0
20
40
60
80
100
TEMPERATURE (˚C)
* Multiply value at 25˚C by this factor to
determine the value at temperature
FIGURE 2-7:
Normalized I
OL
vs. Temperature
DS11187C-page 4
Preliminary
©
1999 Microchip Technology Inc.
MCP100/101
1.08
800
V
DD
= 2.5V
700
V
DD
- V
OH
(mV)
600
NORMALIZED V
OH
*
500
400
300
200
100
T
A
= +25°C
0
0
2
4
6
8
10
0.88
-40
-20
0
20
40
60
80
100
V
DD
= 5V
V
DD
= 3.5V
1.06
1.04
1.02
1.00
0.98
0.96
0.94
0.92
0.90
V
DD
=3V
I
OH
=3.2mA
V
DD
=4.5V
I
OH
=8.5mA
TEMPERATURE (˚C)
* Multiply value at 25˚C by this factor to
determine the value at temperature
I
OH
(mA)
FIGURE 2-8:
V
DD
- V
OH
vs. I
OH
FIGURE 2-9:
Normalized V
OH
vs. Temperature
©
1999 Microchip Technology Inc.
Preliminary
DS11187C-page 5
