AD ADM6384 Microprocessor supervisory circuit in 4-lead sc70 Datasheet

Microprocessor Supervisory
Circuit in 4-Lead SC70
ADM6384
FEATURES
FUNCTIONAL BLOCK DIAGRAMS
ADM6384
VCC
RESET
GENERATOR
VREF
MR
RESET
GND
DEBOUNCE
05305-001
Precision power supply monitoring
31 reset threshold options
1.58 V to 5.0 V
Four reset timeouts
1 ms, 20 ms, 140 ms, 1120 ms
Manual reset input
Reset output stage
Push-pull active-low
Guaranteed reset output valid to VCC = 1 V
Power supply glitch immunity
Specified over −40°C to +125°C temperature range
4-lead SC70 package
Figure 1.
VCC
VCC
APPLICATIONS
μP
ADM6384
MR
RESET
RESET
100kΩ
GND
GND
05305-002
Microprocessor systems
Computers
Controllers
Intelligent instruments
Portable equipment
Figure 2.
GENERAL DESCRIPTION
The ADM6384 is a supervisory circuit that monitors power
supply voltage levels in microprocessor-based systems. A
power-on reset signal is generated when the supply voltage
rises to a preset threshold level. The debounced manual reset
input of the ADM6384 can be used to initiate a reset by means
of an external push-button or logic signal.
The part is available in a choice of 31 reset threshold options,
from 1.58 V to 5.0 V. The minimum reset timeout periods are
1 ms, 20 ms, 140 ms, and 1120 ms.
The ADM6384 is available in a 4-lead SC70 package and typically consumes only 7 μA, making it suitable for use in low
power, portable applications.
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
© 2005 Analog Devices, Inc. All rights reserved.
ADM6384
TABLE OF CONTENTS
Specifications..................................................................................... 3
Manual Reset Input .......................................................................9
Absolute Maximum Ratings............................................................ 5
Application Information................................................................ 10
ESD Caution.................................................................................. 5
Negative-Going VCC Transients ................................................ 10
Pin Configuration and Function Descriptions............................. 6
Ensuring Reset Valid to VCC = 0 V ........................................... 10
Typical Performance Characteristics ............................................. 7
Outline Dimensions ....................................................................... 11
Circuit Description........................................................................... 9
Ordering Guide .......................................................................... 11
Reset Output ................................................................................. 9
REVISION HISTORY
7/05—Revision 0: Initial Version
Rev. 0 | Page 2 of 12
ADM6384
SPECIFICATIONS
VCC = full operating range; TA = −40°C to +125°C, unless otherwise noted.
Table 1.
Parameter
SUPPLY
VCC Operating Voltage Range
Supply Current
RESET THRESHOLD VOLTAGE
ADM6384x50x
ADM6384x49x
ADM6384x48x
ADM6384x47x
ADM6384x46x
ADM6384x45x
ADM6384x44x
ADM6384x43x
ADM6384x42x
ADM6384x41x
ADM6384x40x
ADM6384x39x
ADM6384x38x
ADM6384x37x
ADM6384x36x
ADM6384x35x
ADM6384x34x
ADM6384x33x
ADM6384x32x
ADM6384x31x
ADM6384x30x
ADM6384x29x
ADM6384x28x
ADM6384x27x
ADM6384x26x
ADM6384x25x
ADM6384x24x
ADM6384x23x
ADM6384x22x
ADM6384x17x
ADM6384x16x
RESET THRESHOLD TEMPERATURE COEFFICIENT
VCC to RESET DELAY
RESET THRESHOLD HYSTERESIS
RESET TIMEOUT PERIOD
ADM6384xxD1
ADM6384xxD2
ADM6384xxD3
ADM6384xxD4
Min
Typ
1
7
6
4
3
4.88
4.78
4.68
4.58
4.51
4.39
4.27
4.19
4.1
4.0
3.9
3.8
3.71
3.61
3.51
3.41
3.32
3.22
3.12
3.00
2.93
2.85
2.73
2.63
2.56
2.44
2.34
2.26
2.13
1.62
1.54
5.00
4.90
4.80
4.70
4.63
4.5
4.38
4.30
4.2
4.1
4.0
3.9
3.8
3.7
3.6
3.5
3.4
3.3
3.2
3.08
3.0
2.93
2.8
2.70
2.63
2.5
2.4
2.31
2.19
1.67
1.58
60
35
Max
5.5
13
11
7
6
V
μA
μA
μA
μA
5.12
5.02
4.92
4.82
4.74
4.61
4.48
4.41
4.31
4.2
4.1
4.0
3.9
3.79
3.69
3.59
3.49
3.38
3.28
3.15
3.08
3.00
2.87
2.77
2.69
2.56
2.46
2.37
2.24
1.71
1.61
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
ppm/°C
μs
2 x VTH
1
20
140
1120
Rev. 0 | Page 3 of 12
Unit
mV
2
40
280
2240
ms
ms
ms
ms
Test Conditions/Comments
VCC = 5.5 V, no load
VCC = 3.6 V, no load
VCC = 2.5 V, no load 1
VCC = 1.8 V, no load1
VCC falling at 10 mV/μs from VTH +
100 mV to VTH − 100 mV
ADM6384
Parameter
MANUAL RESET INPUT
MR Input Threshold
VIL
Min
VIH
0.7 × VCC
2.4
1
MR Input Pulse Width
MR Glitch Rejection
MR Pull-Up Resistance
MR to Reset Delay
Typ
0.3 × VCC
0.8
100
63
200
32
RESET Output Voltage
VOL
VOH
1
Max
100
0.3
0.3
0.4
0.8 × VCC
0.8 × VCC
TA = 25oC only.
Rev. 0 | Page 4 of 12
Unit
Test Conditions/Comments
V
V
V
V
μs
ns
kV
ns
VCC < 4 V
VCC > 4 V
VCC < 4 V
VCC > 4 V
V
V
V
V
V
VCC > = 1.0 V, ISINK = 80 μA
VCC > = 2.5 V, ISINK = 1.2 mA
VCC > = 4.5 V, ISINK = 3.2 mA
VCC > = 2.5 V, ISOURCE = 500 μA
VCC > = 4.5 V, I SOURCE = 800 μA
ADM6384
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 2.
Parameter
VCC
RESET
Output Current ( RESET)
Operating Temperature Range
Storage Temperature Range
θJA Thermal Impedance, SC70
Soldering Temperature
Sn/Pb
Pb-Free
Rating
−0.3 V to +6 V
−0.3 V to +6 V
20 mA
−40°C to +125°C
−65°C to +150°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
331°C/W
240°C, 30 sec
260°C, 40 sec
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
Rev. 0 | Page 5 of 12
ADM6384
GND 1
4
VCC
3
MR
ADM6384
TOP VIEW
(Not to Scale)
RESET 2
05305-003
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Figure 3. Pin Configuration
Table 3. Pin Function Descriptions
Pin No.
1
2
Name
GND
RESET
3
MR
4
VCC
Description
Ground.
Active-Low Reset Output. Asserted whenever VCC is below the reset threshold, VTH.
Push-pull output stage.
Manual Reset Input. This is an active-low input which, when forced low for at least 1 μs,
generates a reset. It features a 52 kV internal pull-up.
Power Supply Voltage Being Monitored.
Rev. 0 | Page 6 of 12
ADM6384
TYPICAL PERFORMANCE CHARACTERISTICS
10.0
1.05
9.5
1.04
NORMALIZED RESET THRESHOLD
9.0
8.5
8.0
7.0
6.5
6.0
5.5
5.0
4.5
1.01
1.00
0.99
0.98
0.97
0.96
4.0
–20
0
20
40
60
TEMPERATURE (°C)
80
100
120
0.95
–40
04535-006
3.5
–40
1.02
Figure 4. Supply Current vs. Temperature
–20
0
20
40
60
TEMPERATURE (°C)
80
100
120
04535-010
ICC (μA)
7.5
1.03
Figure 7. Normalized Reset Threshold vs. Temperature
100
0.20
90
0.15
70
60
VOUT (V)
VCC TO RESET DELAY (μs)
80
50
40
0.10
30
0.05
20
10
20
40
60
TEMPERATURE (°C)
80
100
120
0
0
Figure 5. VCC to RESET Output Delay vs. Temperature
1
2
3
4
ISINK (mA)
5
6
7
04535-017
0
1.0
04535-018
–20
04535-008
0
–40
Figure 8. Output Voltage Low vs. ISINK
1.20
2.92
2.90
1.10
1.05
VOUT (V)
2.88
1.00
0.95
2.86
0.90
2.84
0.85
0.80
–40
–20
0
20
40
60
TEMPERATURE (°C)
80
100
120
04535-007
NORMALIZED RESET TIMEOUT
1.15
Figure 6. Normalized Reset Timeout Period vs. Temperature
2.82
0
0.2
0.4
0.6
ISOURCE (mA)
0.8
Figure 9. Output Voltage High vs. ISOURCE
Rev. 0 | Page 7 of 12
ADM6384
340
140
120
100
VTH = 4.63V
80
60
40
20
VTH = 2.93V
0
10
100
OVERDRIVE VOD (mV)
1000
Figure 10. Maximum VCC Transient Duration vs. Reset Threshold Overdrive
Rev. 0 | Page 8 of 12
320
300
280
260
240
220
200
180
160
140
120
100
–40
–20
0
20
40
60
TEMPERATURE (°C)
80
100
120
Figure 11. Manual Reset Minimum Pulse Width vs. Temperature
05305-011
MANUAL RESET TO RESET DELAY (ns)
RESET OCCURS ABOVE CURVE
05305-010
MAXIMUM TRANSIENT DURATION (μs)
160
ADM6384
CIRCUIT DESCRIPTION
RESET OUTPUT
The ADM6384 features an active-low push-pull reset output.
The reset signal is guaranteed to be logic low for VCC down
to 1 V.
The reset output is asserted when VCC is below the reset
threshold (VTH) or when MR is driven low. Reset remains
asserted for the duration of the reset active timeout period
(tRP) after VCC rises above the reset threshold or after MR
transitions from low to high. Figure 12 illustrates the behavior
of the reset outputs.
VCC
VCC
VTH
VTH
1V
0V
VCC
RESET
tRP
0V
tRD
05305-012
The ADM6384 provides microprocessor supply voltage
supervision by controlling the microprocessor’s reset input.
Code execution errors are avoided during power-up, powerdown, and brownout conditions by asserting a reset signal
when the supply voltage is below a preset threshold. In addition,
the ADM6384 allows supply voltage stabilization with a fixed
timeout before the reset deasserts after the supply voltage
rises above the threshold. If the user detects a problem with
the system’s operation, a manual reset input is available to reset
the microprocessor by means of an external push-button,
for example.
Figure 12. Reset Timing Diagram
MANUAL RESET INPUT
The ADM6384 features a manual reset input (MR) which, when
driven low, asserts the reset output. When MR transitions from
low to high, reset remains asserted for the duration of the reset
active timeout period before deasserting. The MR input has a
52 kΩ internal pull-up so that the input is always high when
unconnected. An external push-button switch can be connected
between MR and ground so that the user can generate a reset.
Debounce circuitry for this purpose is integrated on-chip. Noise
immunity is provided on the MR input, and fast, negative-going
transients of up to 100 ns (typ) are ignored. A 0.1 μF capacitor
between MR and ground provides additional noise immunity.
Rev. 0 | Page 9 of 12
ADM6384
APPLICATION INFORMATION
NEGATIVE-GOING VCC TRANSIENTS
ENSURING RESET VALID TO VCC = 0 V
To avoid unnecessary resets caused by fast power supply
transients, the ADM6384 is equipped with glitch rejection
circuitry. The typical performance characteristic in Figure 10
plots VCC transient duration versus the transient magnitude.
The curves show combinations of transient magnitude and
duration for which a reset is not generated for 4.63 V and
2.93 V reset threshold parts. For example, with the 2.93 V
threshold, a transient that goes 100 mV below the threshold
and lasts 8 μs typically does not cause a reset, but if the transient
is any bigger in magnitude or duration, a reset is generated. An
optional 0.1 μF bypass capacitor mounted close to VCC provides
additional glitch rejection.
Both active-low and active-high reset outputs are guaranteed to
be valid for VCC as low as 1 V. However, by using an external
resistor with push-pull configured reset outputs, valid outputs
for VCC as low as 0 V are possible. For an active-low reset
output, a resistor connected between RESET and ground pulls
the output low when it is unable to sink current. A large
resistance such as 100 kΩ should be used so that it does not
overload the reset output when VCC is above 1 V.
VCC
ADM6384
RESET
05305-013
100kΩ
GND
Figure 13. Ensuring Reset Valid to VCC = 0 V
Rev. 0 | Page 10 of 12
ADM6384
OUTLINE DIMENSIONS
2.20
1.80
1.35
1.15
3
4
1
2.40
1.80
2
PIN 1
0.50 BSC
0.65 BSC
1.10
0.80
1.00
0.80
0.10 MAX
0.30
0.15
12°
8°
0.40
0.10
SEATING
*0.70 PLANE
0.50
0.18
0.10
0.30
0.10
0.10 COPLANARITY
*PACKAGE OUTLINE CORRESPONDS IN FULL TO EIAJ SC82
EXCEPT FOR WIDTH OF PIN-2 AS SHOWN
Figure 14. 4-Lead Thin Shrink Small Outline Transistor Package [SC70]
(KS-4)
Dimensions shown in millimeters
ADM6384YKS_
x_
x D_-RL7
x
ORDERING QUANTITY
RL7: 3,000 PIECE REEL
RESET TIMEOUT PERIOD
1: 1ms (MIN)
2: 20ms (MIN)
3: 140s (MIN)
4: 1120s (MIN)
PACKAGE CODE
KS: 4-LEAD SC70
Z: LEAD FREE
RESET THRESHOLD NUMBER
(16 TO 50)
05305-014
GENERIC NUMBER
TEMPERATURE RANGE
Y: –40°C TO +125°C
Figure 15. Ordering Code Structure
ORDERING GUIDE
Standard Models 1
ADM6384YKS29D1-RL7
ADM6384YKS23D3-RL7
ADM6384YKS29D3-RL7
1
Reset Threshold (V)
2.93
2.31
2.93
Reset Timeout (ms)
1
140
140
Temperature Range
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
Quantity
3k
3k
3k
Package Type
SC70-4
SC70-4
SC70-4
Branding
N0J
N0J
N0J
If ordering nonstandard models, complete the ordering code shown in Figure 15 by inserting reset timeout and reset threshold suffixes. Contact Sales for availability
of nonstandard models.
Rev. 0 | Page 11 of 12
ADM6384
NOTES
© 2005 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05305–0–7/05(0)
Rev. 0 | Page 12 of 12
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