TCM809
TCM810
3-Pin Microprocessor Reset Monitors
FEATURES
s
s
s
s
s
s
s
Precision V
CC
Monitor for 2.5, 3.0V, 3.3V, 5.0V
Nominal System Voltage Supplies
140msec Guaranteed Minimum RESET, RESET
Output Duration
RESET Output Guaranteed to V
CC
= 1.0V (TCM809)
Low 12
µ
A Supply Current
V
CC
Transient Immunity
Small 3-Pin SC-70 and SOT-23B Packages
No External Components
GENERAL DESCRIPTION
The TCM809 and TCM810 are cost-effective system
supervisor circuits designed to monitor V
CC
in digital sys-
tems and provide a reset signal to the host processor when
necessary. No external components are required.
The reset output is driven active within 20
µsec
of V
CC
falling through the reset voltage threshold. Reset is main-
tained active for a minimum of 140msec after V
CC
rises
above the reset threshold. The TCM810 has an active-high
RESET output while the TCM809 has an active-low RESET
output. The output of the TCM809 is guaranteed valid down
to V
CC
= 1V. Both devices are available in 3-Pin SOT-23B
and SC-70 packages.
The TCM809/810 are optimized to reject fast transient
glitches on the V
CC
line. Low supply current of 12µA (V
CC
=
3.3V) makes these devices suitable for battery powered
applications.
TYPICAL APPLICATIONS
s
s
s
s
s
Computers
Embedded Systems
Battery Powered Equipment
Critical
µ
P Power Supply Monitoring
Automotive
TYPICAL OPERATING CIRCUIT
V
CC
3
V
CC
TCM809
RESET
2
V
CC
PROCESSOR
RESET
INPUT
GND
ORDERING INFORMATION
Part No.
TCM809xENB
TCM809xVNB
TCM809xVXX
TCM810xENB
TCM810xVNB
TCM810xVXX
Package
3-Pin SOT-23B
3-Pin SOT-23B
3-Pin SC-70
3-Pin SOT-23B
3-Pin SOT-23B
3-Pin SC-70
Temp. Range
– 40°C to +85°C
– 40°C to +125°C
– 40°C to +125°C
– 40°C to +85°C
– 40°C to +125°C
– 40°C to +125°C
NOTE: The "x" denotes a suffix for V
CC
threshold - see table below.
GND
1
Suffix
L
M
J
T
S
R
Z
Reset V
CC
Threshold (V)
4.63
4.38
4.00
3.08
2.93
2.63
2.32
PIN CONFIGURATION
*3-Pin SOT-23B/SC-70
GND
1
TCM809x
TCM810x
NOTE: J version is available for TCM809 only.
3
VCC
RESET**(RESET)
2
NOTE: *3-Pin SOT-23B is equivalent to JEDEC TO-236
** () is for TCM810
2001 Microchip Technology Inc.
DS21602A
TCM809/810-5
10/10/00
3-Pin Microprocessor Reset Monitors
TCM809
TCM810
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage (V
CC
to GND) ................................ +6.0V
RESET, RESET ............................ – 0.3V to (V
CC
+ 0.3V)
Input Current, V
CC
.. .................................................. 20mA
Output Current, RESET, RESET ............................. 20mA
dV/dt (V
CC
) ....................................................... 100V/µsec
Operating Temperature Range ............. – 40°C to +125°C
Power Dissipation (T
A
≤
70°C)
3-Pin SOT-23B (derate 4mW/°C above +70°C) 230mW
3-Pin SC-70 (derate 2.17mW/°C above +70°C) 174mW
Storage Temperature Range ................ – 65°C to +150°C
Lead Temperature (Soldering, 10 sec) ................. +260°C
*This is a stress rating only and functional operation of the device at these
or any other conditions above those indicated in the operational sections of
the specifications is not implied. Exposure to Absolute Maximum Rating
Conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS:
Symbol Parameter
V
CC
Range
I
CC
I
CC
V
TH
Supply Current (SOT-23)
Supply Current (SC-70)
Reset Threshold (Note 2)
Vcc = Full Range, T
A
= Operating Temperature Range unless other-
wise noted. Typical values are at T
A
= +25°C, V
CC
= 5V for L/M/J, 3.3V forT/S, 3.0V for R, and 2.5V for Z (Note 1).
Test Conditions
T
A
= 0°C to +70°C
T
A
= – 40°C to +125°C
TCM8xxL/M/J V
CC
< 5.5V
TCM8xxR/S/T/Z: V
CC
< 3.6V
TCM8xxL/M/J V
CC
< 5.5V
TCM8xxR/S/T/Z: V
CC
< 3.6V
TCM8xxL: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM8xxM: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM809J: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM8xxT: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM8xxS: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM8xxR: T
A
= +25°C
T
A
= – 40°C to +125°C
TCM8xxZ: T
A
= +25°C
T
A
= – 40°C to +125°C
Min
Typ
—
—
24
17
16
12
4.63
—
4.38
—
4.00
—
3.08
—
2.93
—
2.63
—
2.32
—
30
20
240
—
—
—
—
—
—
—
—
Max
5.5
5.5
60
50
35
30
4.70
4.75
4.45
4.50
4.06
4.10
3.11
3.15
2.96
3.00
2.66
2.70
2.35
2.38
—
—
560
0.3
0.4
0.3
—
—
0.3
0.4
—
Unit
V
µA
µA
V
V
OL
Reset Threshold Tempco
V
CC
to Reset Delay (Note 2)
Reset Active Timeout Period
RESET Output Voltage Low
(TCM809)
RESET Output Voltage High
(TCM809)
RESET Output Voltage Low
(TCM810)
RESET Output Voltage High
(TCM810)
V
OH
V
OL
V
OH
NOTES:
1.0
1.2
—
—
—
—
4.56
4.50
4.31
4.25
3.93
3.89
3.04
3.00
2.89
2.85
2.59
2.55
2.28
2.25
—
V
CC
= V
TH
to (V
TH
– 100mV)
—
140
TCM809R/S/T/Z: V
CC
= V
TH
min, I
SINK
= 1.2mA
—
—
TCM809L/M/J: V
CC
= V
TH
min, I
SINK
= 3.2mA
V
CC
> 1.0V, I
SINK
= 50µA
—
TCM809R/S/T/Z: V
CC
> V
TH
max, I
SOURCE
= 500µA 0.8 V
CC
TCM809L/M/J: V
CC
> V
TH
max, I
SOURCE
= 800µA V
CC
– 1.5
TCM810R/S/T/Z: V
CC
= V
TH
max, I
SINK
= 1.2mA
—
TCM810L/M/J: V
CC
= V
TH
max, I
SINK
= 3.2mA
—
1.8 < V
CC
< V
TH
min, I
SOURCE
= 150µA
0.8 V
CC
ppm/°C
µsec
msec
V
V
V
V
1. Production testing done at T
A
= +25°C, over temperature limits guaranteed by design.
2. RESET output for TCM809, RESET Output for TCM810.
TCM809/810-5 10/10/00
2
2001 Microchip Technology Inc.
DS21602A
3-Pin Microprocessor Reset Monitors
TCM809
TCM810
PIN DESCRIPTION
Pin No.
1
2
2
3
Symbol
GND
RESET (TCM809)
RESET (TCM810)
V
CC
Description
Ground
RESET output remains low while V
CC
is below the reset voltage threshold, and
for 240msec (140msec min.) after V
CC
rises above reset threshold.
RESET output remains high while V
CC
is below the reset voltage threshold,
and for 240msec (140msec min.) after V
CC
rises above reset threshold.
Supply voltage (+2.5V, +3.0V, +3.3V, +5.0V)
APPLICATIONS INFORMATION
V
CC
Transient Rejection
The TCM809/810 provides accurate V
CC
monitoring
and reset timing during power-up, power-down, and brown-
out/sag conditions, and rejects negative-going transients
(glitches) on the power supply line. Figure 1 shows the
maximum transient duration vs. maximum negative excur-
sion (overdrive) for glitch rejection. Any combination of
duration and overdrive which lies
under
the curve will
not
generate a reset signal.
Combinations above the curve are detected as a brown-
out or power-down. Transient immunity can be improved by
adding a capacitor in close proximity to the V
CC
pin of the
TCM809/810.
RESET Signal Integrity During Power-Down
The TCM809 RESET output is valid to V
CC
= 1.0V.
Below this voltage the output becomes an "open circuit" and
does not sink current. This means CMOS logic inputs to the
µP
will be floating at an undetermined voltage. Most digital
systems are completely shutdown well above this voltage.
However, in situations where RESET must be maintained
valid to V
CC
= 0V, a pull-down resistor must be connected
from RESET to ground to discharge stray capacitances and
hold the output low (Figure 2). This resistor value, though not
critical, should be chosen such that it does not appreciably
load RESET under normal operation (100kΩ will be suitable
for most applications). Similarly, a pull-up resistor to V
CC
is
required for the TCM810 to ensure a valid high RESET for
V
CC
below 1.0V.
V
CC
V
TH
Overdrive
Duration
MAXIMUM TRANSIENT DURATION (µsec)
400
T
A
= +25°C
320
V
CC
240
V
CC
TCM809
TCM8XXL/M/J
TCM8XXZ/R/S/T
1
5
1000
100
RESET COMPARATOR OVERDRIVE,
160
80
0
RESET
R1
100k
GND
[
VTH - VCC
]
(mV)
Figure 1. Maximum Transient Duration vs.
Overdrive for Glitch Rejection at 25
°
C
2001 Microchip Technology Inc.
DS21602A
Figure 2. Ensuring RESET Valid to V
CC
= 0V
3
TCM809/810-5
10/10/00
3-Pin Microprocessor Reset Monitors
TCM809
TCM810
Processors With Bidirectional I/O Pins
Some
µPs
(such as Motorola 68HC11) have bi-direc-
tional reset pins. Depending on the current drive capability
of the processor pin, an indeterminate logic level may result
if there is a logic conflict. This can be avoided by adding a
4.7kΩ resistor in series with the output of the TCM809/810
(Figure 3). If there are other components in the system which
require a reset signal, they should be buffered so as not to
load the reset line. If the other components are required to
follow the reset I/O of the
µP,
the buffer should be connected
as shown with the solid line.
BUFFER
BUFFERED RESET
TO OTHER SYSTEM
COMPONENTS
V
CC
V
CC
TCM809
4.7k
RESET
RESET
V
CC
µP
GND
GND
Figure 3. Interfacing to Bidirectional Reset I/O
TCM809/810-5 10/10/00
4
2001 Microchip Technology Inc.
DS21602A
3-Pin Microprocessor Reset Monitors
TCM809
TCM810
TYPICAL CHARACTERISTICS
Supply Current vs.Temperature
(No Load, TCM8xxZ/R/S/T)
35
30
SUPPLY CURRENT (µA)
Supply Current vs.Temperature
(No Load, TCM8xxL/M/J)
30
VCC = 5V
25
SUPPLY CURRENT (µA)
VCC = 5V
25
20
15
10
5
0
–40
VCC = 1V
VCC = 3V
20
15
10
5
0
–40
VCC = 1V
VCC = 3V
–20
0
20
40
60
80
100
125
–20
0
20
40
60
80
100
125
TEMPERATURE (°C)
TEMPERATURE (°C)
Power-Down Reset Delay vs. Temperature
(TCM8xxZ/R/S/T)
POWER-DOWN RESET DELAY (µsec)
Power-Down Reset Delay vs. Temperature
(TCM8xxL/M/J)
POWER-DOWN RESET DELAY (µsec)
100
VOD = VTH – VCC
VOD = 10mV
140
VOD = VTH – VCC
120
100
80
60
40
VOD = 100mV
20
0
–40
VOD = 200mV
–20
0
20
40
60
80
100
125
TEMPERATURE (°C)
VOD = 20mV
VOD = 10mV
80
60
VOD = 20mV
40
20
VOD = 100mV
VOD = 200mV
–20
0
20
40
60
80
100
125
TEMPERATURE (°C)
0
–40
Power-Up Reset Timeout vs. Temperature
POWER-UP RESET TIMEOUT (msec)
Normalized Reset Threshold vs. Temperature
1.003
NORMALIZED THRESHOLD
250
245
TCM8xxL/M/J
240
1.002
1.001
1.000
0.999
0.998
0.997
235
TCM8xxZ/R/S/T
230
225
–40
–20
0
20
40
60
80
100
125
–40
–20
0
20
40
60
80
100
125
TEMPERATURE (°C)
2001 Microchip Technology Inc.
DS21602A
TEMPERATURE (°C)
5
TCM809/810-5
10/10/00
Microcontroller MCU
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