Diodes AP1701 3-pin microprocessor reset circuit Datasheet

AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
General Description
Features
•
•
•
The AP1701/2/3/4 are used for microprocessor (µP) supervisory
circuits to monitor the power supplies in µP and digital systems.
They provide excellent circuit reliability and low cost by
eliminating external components and adjustments when used
with +5V, +3.3V, +3.0V powered circuits.
Precision Monitoring of +2.5V, +3V, +3.3V, and +5V
Power-Supply Voltages
Fully Specified Over Temperature
Available in three Output Configurations
•
Push-Pull RESET Low Output (AP1701/3)
•
•
•
•
•
•
•
•
Push-Pull RESET High Output (AP1702/4)
200ms Min. Power-On Reset Pulse Width
20µA Supply Current (Typ.)
Guaranteed Reset Valid to VCC = +1V
Power Supply Transient Immunity
No External Components
Green Package: SC59-3L
Lead Free Finish / RoHS Compliant (Note1)
These circuits perform a single function: they assert a reset
signal whenever the VCC supply voltage declines below a preset
threshold, keeping it asserted for at least 240ms after VCC has
risen above the reset threshold. Reset thresholds suitable for
operation with a variety of supply voltages are available. The
AP1701/2/3/4 have push pull outputs. The AP1701/3 have an
active low RESET output, while the AP1702/4 has an active
high RESET output. The reset comparator is designed to ignore
fast transients on VCC, and the outputs are guaranteed to be in
the correct logic state for VCC down to 1V. Low supply current
makes the AP1701/2/3/4 ideal for use in portable equipment. The
AP1701/2/3/4 is available in a 3-pin SC59 package.
Applications
•
•
•
•
•
•
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery Powered Equipment
Automotive
Ordering Information
AP170X X X X X
1
2
3
4
Enable
Voltage
: Active-Low
: Active-High
: Active-Low
: Active-High
A
B
C
D
E
F
G
Package
: 4.63
: 4.38
: 4.00
: 3.08
: 2.93
: 2.63
: 2.25
W
: SC59
Lead Free
Packing
L : Lead Free
G : Green
-7 : Taping
Notes: 1. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7.
Device
AP170XXW
Package Packaging
Code
(Note 2)
W
SC59
Quantity
7” Tape and Reel
Part Number Suffix
3000/Tape & Reel
-7
Notes: 2. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf.
AP1701/2/3/4 Rev. 2
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Pin Assignments
(Top View)
GND
(Top View)
1
RESET (RESET)
AP1701
AP1702
RESET (RESET)
1
AP1703
AP1704
3 VCC
GND
2
3 VCC
2
SC59-3L
SC59-3L
Pin Descriptions
Name
Description
GND
Ground
Reset Output Pin
L: for AP1701/3
H: for AP1702/4
Operating Voltage Input
RESET
(RESET)
VCC
Absolute Maximum Ratings
Symbol
VCC
VRESET
ICC
IO
Parameter
Terminal Voltage (with respect to GND)
RESET, RESET (push-pull)
Input Current, VCC
Rating
Unit
-0.3 to +6.0
V
-0.3 to (VCC + 0.3)
V
20
mA
20
mA
320
mW
TOP
Output Current, RESET, RESET
Continuous Power Dissipation (TA = +70°C),
de-rate 4mW/°C above +70°C
Operating Junction Temperature Range
-40 to +105
°C
TST
Storage Temperature Range
-65 to +150
°C
PD
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Electrical Characteristics
(TA = 25ºC)
Symbol
Parameter
VCC
VCC Range
ICC
Supply Current
VTH
TS
TDELAY
VOL
VOH
VOL
VOH
Conditions
TA = 0oC to +70oC
VTH + 1.0V
AP1701/2/3/4A
AP1701/2/3/4B
AP1701/2/3/4C
Reset Threshold
AP1701/2/3/4D
TA = 25ºC
AP1701/2/3/4E
AP1701/2/3/4F
AP1701/2/3/4G
Reset Threshold
Tempco
Set-up Time
VCC = 0 to (VTH – 100mV)
Reset Active
TA = 0oC to +70oC
Timeout Period
VCC = VTH min, ISINK = 1.2mA, AP1701/3
RESET Output V = V min, I
CC
TH
SINK = 3.2mA
Voltage Low
VCC > 1.0V, ISINK = 50uA
RESET Output VCC > VTH max, ISOURCE = 500uA, AP1701/3
VCC > VTH max, ISOURCE = 800uA
Voltage-High
RESET Output VCC = VTH max, ISINK = 1.2mA, AP1702/4
Voltage-Low
VCC = VTH max, ISINK = 3.2mA
RESET Output 1.8V < VCC < VTH min, ISOURCE = 150uA,
Voltage-High
AP1702/4
Min.
1.0
4.54
4.29
3.92
3.02
2.87
2.57
2.20
Typ.
20
4.63
4.38
4.00
3.08
2.93
2.63
2.25
Max.
5.5
30
4.72
4.47
4.08
3.14
2.99
2.68
2.30
100
240
600
ms
0.3
0.4
0.3
V
0.8VCC
VCC –1.5
V
0.3
0.4
0.8 VCC
V
ppm/
o
C
µs
30
100
Unit
V
µA
V
V
Typical Application Circuit
V CC
Cin
0.1uF
V CC
V CC
AP170X
RESET
(RESET)
GND
AP1701/2/3/4 Rev. 2
Microprocessor
RESET
INPUT
GND
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Function Description
A microprocessor’s (µP’s) reset input starts the µP in a
known state. The AP1701/2/3/4 assert reset to prevent
code-execution errors during power-up, power-down, or
brownout conditions. They assert a reset signal whenever the VCC
supply voltage declines below a preset threshold, keeping it
asserted for at least 240ms after VCC has risen above the reset
threshold. The AP1701/2/3/4 have a push-pull output stage.
Applications Information
Negative-Going VCC Transients
In addition to issuing a reset to the µP during power-up,
power-down, and brownout conditions, the AP1701/2/3/4 are
relatively immune to short-duration negative-going VCC transients
(glitches).
The AP1701/2/3/4 do not generate a reset pulse. The
graph was generated using a negative going pulse applied to VCC,
starting 0.5V above the actual reset threshold and ending below it
by the magnitude indicated (reset comparator overdrive). The
graph indicates the maximum pulse width a negative going VCC
transient can have without causing a reset pulse. As the
magnitude of the transient increases (goes farther below the
reset threshold), the maximum allowable pulse width decreases.
Typically, a VCC transient that goes 100mV below the reset
threshold and lasts 100µs or less will not cause a reset pulse. A
0.1µF bypass capacitor mounted as close as possible to the VCC
pin provides additional transient immunity.
Ensuring a Valid Reset Output
Down to VCC = 0
RESET is guaranteed to be a logic low for VCC > 1V.
Once VCC exceeds the reset threshold, an internal timer keeps
RESET
low for the reset timeout period; after this interval,
RESET
goes high.
below the reset threshold), RESET goes low. Any time VCC
goes below the reset threshold, the internal timer resets to zero,
and
RESET
goes low. The internal timer starts after VCC
returns above the reset threshold, and
for the reset timeout period.
RESET
remains low
When VCC falls below 1V, the AP1701/3 RESET
output no longer sinks current—it becomes an open circuit.
Therefore, high-impedance CMOS logic inputs connected to
RESET can drift to undetermined voltages.
This presents no problem in most applications since most µP and
other circuitry is inoperative with VCC below 1V. However, in
applications where
pull down resistor to
RESET must be valid down to 0V, adding a
RESET
causes any stray leakage
currents to flow to ground, holding
RESET
not critical; 100k are large enough not to load
low. R1’s value is
RESET
and
RESET to ground. For the AP1702/4 if
RESET is required to remain valid for VCC < 1V.
small enough to pull
Benefits of Highly Accurate Reset Threshold
Most µP supervisor ICs has reset threshold voltages
between 5% and 10% below the value of nominal supply voltages.
This ensures a reset will not occur within 5% of the nominal
supply, but will occur when the supply is 10% below nominal.
When using ICs rated at only the nominal supply ±5%, this leaves
a zone of uncertainty where the supply is between 5% and 10%
low, and where the reset may or may not be asserted.
If a brownout condition occurs (VCC dips
RESET
Block Diagram
Driver
Delay Circuit
RESET
/ RESET
VREF
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Performance Characteristics
Threshold
24
2.928
20
2.926
16
Iq 12
2.924
8
2.922
4
0 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120
2.92
0
10 20 30 40 50 60 70 80 90
Temp
Temp ( C )
Iq vs. Temp
AP1701/2/3/4 Rev. 2
-40 -30 -20 -10
Threshold vs. Temp
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Timing Diagram
VTH
VCC
TDELAY
TDELAY
Active Low
TS
Active High
TDELAY
TDELAY
Giltch Immunity
Maximum Transient
Duration(us)
3500
3000
2500
3000
2000
1500
1000
500
900
270
0
0
100
200
140
300
90
400
70
500
58
600
50
700
50
800
48
48
900 1000 1100
RESET COMPARATOR OVERDRIVE(mV)
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Marking Information
(1) SC59-3L
(Top View)
3
XX : Identification code
: Year 0-9
Y
: Month A~L
M
L
: Lead Free Package
G
: Green Package
XX Y M X
1
Device
AP1701AW
AP1701BW
AP1701CW
AP1701DW
AP1701EW
AP1701FW
AP1701GW
AP1702AW
AP1702BW
AP1702CW
AP1702DW
AP1702EW
AP1702FW
AP1702GW
AP1703AW
AP1703BW
AP1703CW
AP1703DW
AP1703EW
AP1703FW
AP1703GW
AP1704AW
AP1704BW
AP1704CW
AP1704DW
AP1704EW
AP1704FW
AP1704GW
Notes:
2
Package
(Note 3)
Identification Code
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
SC59
EA
EB
EC
ED
EE
EF
W1
E0
E2
E3
E4
E5
E6
W2
EG
EH
EI
EJ
EK
EL
W3
E7
E8
E9
EM
EN
EP
W4
3. For Packaging Details, go to our website at http://www.diodes.com/datasheets/ap02007.pdf.
AP1701/2/3/4 Rev. 2
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
Package Information
(All Dimensions in mm)
(1) Package Type: SC59-3L
TOP VIEW
1.50/
1.70
0.35/0.50
2.70/
3.00
1.90
2.90/3.10
1.00/
1.30
0.013/0.10
0.10/0.20
0.95
0.35/0.55
0°/8°
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AP1701/2/3/4
3-PIN MICROPROCESSOR RESET CIRCUITS
IMPORTANT NOTICE
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further
notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither
does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall assume all risks of such use and will
agree to hold Diodes Incorporated and all the companies whose products are represented on our website, harmless against all damages.
LIFE SUPPORT
Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the
President of Diodes Incorporated.
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