MIC2794 - Micrel

MIC2794
Supervisor with Fast Propagation Delay and
Capacitor-Programmable
Reset Delay
General Description
Features
The MIC2794 is a low-current supervisor with capacitorprogrammable reset delay time. It provides an active-low
manual reset input and active-low open-drain, active-low
push-pull, or active-high push-pull outputs. The device
initiates a reset signal when the sense input drops below
the threshold voltage (between 0.4V and 4.6V), or the
manual input is asserted low. The active-low reset stays
low for the duration of the reset timeout delay once the
monitored voltage or the manual reset exceed their
thresholds. The reset timeout delay period is
programmable from 1.25ms to 10s with an external
capacitor.
•
•
•
•
The MIC2794 operates from a supply voltage of 1.65V to
5.5V and guarantees an active-low reset output for supply
voltages equal to or greater than 1V. The device is rated to
operate over the temperature range of −40°C to +125°C.
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
•
•
•
•
•
•
1.65V to 5.5V operating supply voltage range
Ultra-low operating current: 2µA (typical)
Fast propagation delay: 20µs (typical)
Fixed threshold voltages and 0.4V reference voltage
(adjustable from 0.4V to 4.6)
− ±2.0% threshold accuracy from –40°C to +125°C
Programmable reset timeout delay (from 1.25ms to 10s)
Manual reset input with an internal pull-up resistor
Active-low/high multiple output options:
− Open-drain active-low (/RESET)
− Push-pull active-low (/RESET)
− Push-pull active-high (RESET)
−40°C to +125°C junction temperature range
6-pin TSOT
6-pin 1.6mm × 1.6mm Thin DFN
Applications
• Microprocessor systems
• Computers, tablets
• Intelligent instruments
Typical Application
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
May 12, 2015
Revision 1.2
Micrel, Inc.
MIC2794
Ordering Information
Marking
Code
Typical
Threshold
Voltage (VTH)
/RESET
Output
(Active-Low)
RESET
Output
(ActiveHigh)
Junction
Temperature
Range
Package
MIC2794H-04VD6
QP
0.400V
−
Push-Pull
–40°C to +125°C
6-pin TSOT
MIC2794L-04VD6
QO
0.400V
Push-Pull
−
–40°C to +125°C
6-pin TSOT
(2, 3)
Part Number
QN
0.400V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QQ
0.840V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QR
1.120V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QU
1.400V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QV
1.670V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QX
2.330V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
QZ
3.070V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
(1)
MIC2794N-46VD6
BQ
4.650V
Open-Drain
−
–40°C to +125°C
6-pin TSOT
MIC2794H-04VMT
QC
0.400V
−
Push-Pull
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794L-04VMT
QB
0.400V
Push-Pull
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-04VD6
MIC2794N-08VD6
MIC2794N-11VD6
MIC2794N-14VD6
MIC2794N-16VD6
MIC2794N-23VD6
MIC2794N-30VD6
QA
0.400V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-08VMT
(1)
QD
0.840V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-11VMT
(1)
QE
1.120V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-14VMT
(1)
QG
1.400V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-16VMT
(1)
QH
1.670V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-23VMT
(1)
QJ
2.330V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-30VMT
(1)
QL
3.070V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-46VMT
(1)
QM
4.650V
Open-Drain
−
–40°C to +125°C
6-pin 1.6mm × 1.6mm TDFN
MIC2794N-04VMT
Note:
1. Contact factory for availability.
2. All devices are available in Tape & Reel only. (Order entry PN, add TR. Example: MIC2794H-04VD6 TR).
3. Standard/Full reel quantity:
a.
6-pin TSOT: 3,000 pieces per reel, Reel diameter is 7 inches, Hub diameter is 2 inches, Width is 8mm.
b.
6-pin TDFN: 5,000 pieces per reel, Reel diameter is 13 inches, Hub diameter is 7 inches, Width is 8mm.
Part Numbering Convention
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Pin Configuration
6-Pin TSOT (D6)
(Top View)
6-Pin 1.6mm × 1.6mm TDFN (MT)
(Top View)
Pin Description
Pin
Number
TSOT-6
Pin
Number
TDFN
Pin
Name
Pin Function
1
6
/RESET
/RESET is an active-low output pin and is available in an open-drain or push-pull
configuration.
The /RESET pin is asserted low when /MR is set to a logic low or the SNS voltage
decreases below the threshold voltage. /RESET will remain low for the reset timeout delay
after SNS > (VTH + VHYST) and /MR is set to a logic high.
In the open-drain configuration, an external pull-up resistor to VDD is required, the pushpull configuration does not require a pull-up resistor.
1
6
RESET
RESET is an active-high push-pull output and is asserted high when /MR is set to a logic
low or the SNS voltage decreases below the threshold voltage. RESET will remain high for
the reset timeout delay after SNS > (VTH + VHYST) and /MR is set to a logic high.
2
5
GND
Supply Ground.
3
4
CTH
Programmable timeout delay. Connect a capacitor (up to 1.5µF) to ground to set a user
defined reset delay time. Leave this pin unconnected for a reset delay time of 20ms.
Connect to VDD via a resistor (40kΩ to 200kΩ) to set a reset delay time of 320ms.
4
3
/MR
Manual reset is an active-low logic pin and internally pulled to VDD through a 109kΩ pullup resistor. Pulling the /MR input to a logic low asserts /RESET. /RESET will remain low for
the reset timeout delay after /MR is pulled to logic high.
5
2
SNS
Connect-sense pin to the voltage to be monitored or through a resistor divider. When this
voltage decreases below the threshold voltage, VTH, /RESET is asserted low.
6
1
VDD
Supply voltage pin. Bypass this pin to GND with a 1µF capacitor placed as close to the pin
as possible.
−
EP
EP
May 12, 2015
Exposed Pad. Connect to ground plane.
3
Revision 1.2
Micrel, Inc.
MIC2794
Absolute Maximum Ratings(4)
Operating Ratings(5)
Supply Voltage (VDD) .................................... −0.3V to +6.0V
SNS, /MR, CTH.................................................. −0.3V to VDD
/RESET (open drain) ........................................ -0.3V to +6V
/RESET, RESET (push-pull) ................. −0.3V to VDD +0.3V
Lead Temperature (soldering, 10s) ............................ 260°C
Storage Temperature (TS) ......................... −55°C to +150°C
ESD Rating (Human Body Model)(6) .............................. 2kV
ESD Rating (Machine Model)( 6) ................................... 200V
Supply Voltage (VDD) .................................... +1.0V to +5.5V
SNS, /MR, EN, CTH ............................................... 0V to VDD
/RESET, RESET ................................................... 0V to VDD
Junction Temperature (TJ) ........................ −40°C to +125°C
Junction Thermal Resistance
TSOT-6 (θJA) ................................................. 177.2°C/W
1.6mm × 1.6mm TDFN-6 (θJA) ........................ 92.4°C/W
Electrical Characteristics(7)
VDD = 1.65V to 5.5V; RL = 100kΩ; CL = 50pF; TA = 25°C, bold values indicate −40°C ≤ TA ≤ +125°C, unless noted.
Parameter
Condition
Min.
Supply Voltage (VDD)
/RESET output valid
1.65
Power-up Reset Voltage (VDDmin)
Output guaranteed in defined state
Supply Current (IDD)
Sense Threshold Voltage Accuracy
(VTH)
Sense Hysteresis Voltage (VHYST)
Sense Input Bias Current
Sense Pulse Width to Reset
Typ.
Max.
Units
5.5
V
1.0
V
VDD = 3.3V,
CT, /MR = open
/RESET and RESET not asserted
2
VDD = 5V,
CT, /MR = open
/RESET and RESET not asserted
2.5
6
5
µA
VTH = 0.400V
−2.0
±1.0
+2.0
0.8V < VTH < 3.3V
−1.5
±0.5
+1.5
3.3V < VTH < 5.5V
−2.0
±1.0
+2.0
± 1.5
+2.5
%
+25
nA
Sense rising
−25
VSNS = 0.400V
%
VSNS = 5.5V
1.5
µA
VSNS = 1.05 * VTH → 0.95 * VTH
20
µs
20
µs
/RESET & RESET Output Specifications
SNS to /RESET and or RESET
(8)
Propagation Delay
/RESET, RESET Logic Low Output
Voltage
1V ≤ VDD < 1.3V, IOL = 15µA
0.3
1.3V ≤ VDD < 1.8V, IOL = 0.4mA
0.3
1.8V ≤ VDD < 5.5V, IOL = 1mA
0.4
V
1V ≤ VDD < 1.1V, IOH = 1µA
Push-Pull /RESET, RESET Logic High
Output Voltage
1.1V ≤ VDD < 1.3V, IOH = 15µA
1.3V ≤ VDD < 1.8V, IOH = 0.4mA
0.8*VDD
V
1.8V ≤ VDD < 5.5V, IOH = 1mA
Notes:
4. Exceeding the absolute maximum ratings may damage the device.
5. The device is not guaranteed to function outside its operating ratings.
6. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.
7. Specification for packaged product only.
8. SNS to /RESET and or RESET propagation delay is the delay time for SNS voltage to transition from VTH*1.05 to VTH * 0.95 to /RESET and or
RESET assertion.
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Electrical Characteristics(7) (Continued)
VDD = 3.3V; RRESET = 100kΩ; CTH = 1nF; TA = 25°C, bold values indicate −40°C ≤ TA ≤ +125°C, unless noted.
Parameter
Condition
Open Drain /RESET Leakage Current
V/RESET = 5.5V, not asserted
RESET Delay Time
Min.
Typ.
Max.
Units
500
nA
CTH = open
12
14
28
CTH = VDD
180
240
400
CTH = 100pF
0.75
1.25
1.75
CTH = 180nF
700
1200
1700
70
109
kΩ
150
ns
ms
/MR Input Specifications
/MR Internal Pull-Up Resistance
/MR to /RESET and RESET
Propagation Delay
1
/MR Pulse Width to Reset
0.25*VDD
/MR Logic Low Input Voltage
0.75*VDD
/MR Logic High Input Voltage
May 12, 2015
µs
5
V
V
Revision 1.2
Micrel, Inc.
MIC2794
Typical Characteristics
Supply Current
vs. Supply Voltage
1.6
SUPPLY CURRENT (µA)
3
125˚C
2.5
25˚C
2
1.5
1
-40˚C
0.5
1.6
RESET TIMEOUT DELAY (s)
RESET TIMEOUT DELAY (ms)
3.5
1.4
1.2
1
0.8
3
2
4
5
1
0.6
2
3
4
5
6
1
3
2
4
5
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
RESET Timeout Delay
vs. CTH
RESET Timeout Delay
vs. Temperature
RESET Timeout Delay
vs. Temperature
1000
100
10
VDD = 3.3V
1
1.7
1.8
1.6
1.7
RESET TIMEOUT DELAY (s)
RESET TIMEOUT DELAY (ms)
RESET TIMEOUT DELAY (ms)
0.8
0.4
6
10000
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
0.7
VDD = 3.3V
CTH = 100pF
0.6
0.5
1
10
100
1000
10000
-40
-20
CTH (nF)
NORMALIZED SNS THRESHOLD (%)
1.5
1
SNS RISING
0.5
0
-0.5
SNS FALLING
-1
3
4
SUPPLY VOLTAGE (V)
May 12, 2015
20
40
60
80
100
5
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
VDD = 3.3V
CTH = 180nF
0.6
120
-40
-20
0
20
40
60
80
100
120
TEMPERATURE (°C)
SNS Threshold
vs. Temperature
2
2
0
6
1.6
0.7
TEMPERATURE (°C)
Normalized SNS Threshold
vs. Supply Voltage
1
1
SUPPLY VOLTAGE (V)
100000
0.1
1.2
CTH = 180nF
0.6
0
1
1.4
CTH = 100pF
RESET NOT ASSERTED
NORMALIZED SNS THRESHOLD (%)
RESET Timeout Delay
vs. Supply Voltage
RESET Timeout Delay
vs. Supply Voltage
6
2.0
1.5
SNS RISING
1.0
0.5
0.0
-0.5
SNS FALLING
-1.0
-1.5
VDD = 3.3V
-2.0
-40
-20
0
20
40
60
80
100
120
TEMPERATURE (°C)
6
Revision 1.2
Micrel, Inc.
MIC2794
Timing Diagrams
Figure 1. Timeout and Propagation Delay from Sense to /RESET and RESET
Figure 2. Timeout and Propagation Delay from /MR to /RESET and RESET
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Functional Diagram
Figure 3. MIC2794 Functional Block Diagrams
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Functional Description
Design and Product Advantages
The MIC2794 is a highly-responsive supervisor circuit
with a fast propagation delay of 20µs. Additional features
includes a manual reset input pin and a capacitorprogrammable reset timeout delay. The MIC2794 is ideal
for monitoring highly-accurate core voltages that require
quick response in the event of a fault condition. The
capacitor-programmable reset delay helps protect against
an accidental system glitch during a reset timeout.
To set RTOP and RBOTTOM, use Equation 1 and set an
arbitrary RTOP value greater than 100kΩ and solve for
RBOTTOM or vice versa.
VDD
The input supply (VDD) provides power to the
comparators and logic timers. VDD operating range is
1.65V to 5.5V. The reset output is also guaranteed to be
in the correct state with VDD greater than 1V. An input
capacitor of 1µF with a minimum voltage rating of 6.3V is
recommended. Refer to PCB Layout Recommendations
for details.
GND
The ground (GND) pin is the return path for VDD, logic
gates, and output pins. Refer to PCB Layout
Recommendations for details.
RTOP 

VMONITOR = 0.4V ×  1 +

R
BOTTOM


Eq. 1
/MR
Manual reset (/MR) is an active-low input pin that is
internally pull-up to VDD with a 109kΩ resistor. When
/MR is asserted to a logic-low level, /RESET will
transition to a logic low signal while RESET will transition
to a logic high signal. See the Timing Diagrams section
for more information.
CTH
CTH is a programmable timeout delay pin. Connect a
capacitor to ground (from 100pF up to 1.5µF) to set a
reset timeout delay ranging from 1.25ms to 10s. Refer to
the RESET Timeout Delay vs. CTH plot in the Typical
Characteristics section for examples.
/RESET
/RESET is an active-low output and is available in two
output configurations: open-drain or push-pull. The opendrain configuration requires an external pull-up resistor,
while the push-pull doesn’t.
SNS
For fixed voltage threshold parts the sense (SNS) pin can
be connected directly to the monitored voltage. For the
adjustable (-04) part, the sense (SNS) pin monitors the
user’s voltage divided down to a fixed threshold. The
resistor divider network in Figure 4 has to be set in order
for the sense threshold to function properly (0.4V
threshold shown, see the ordering table for threshold
voltage options).
/RESET is asserted low when /MR is set to a logic-low or
the SNS voltage decreases below the threshold voltage.
/RESET will remain low for the programmed reset timeout
delay after SNS > (VTH + VHYST) and /MR is set to a logichigh, and then /RESET will transition high to indicate
normal regulation. See the Timing Diagrams section for
more information.
RESET
RESET is an active-high push-pull output and is asserted
high when /MR is set to a logic low or the SNS voltage
decreases below the threshold voltage. RESET will
remain high for the programmed reset timeout delay after
SNS > (VTH + VHYST) and /MR is set to a logic high, and
then RESET will transition low to indicate normal
regulation. See the Timing Diagrams section for more
information.
Figure 4. Resistor Divider on SNS pin
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Typical Application Schematics
May 12, 2015
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Micrel, Inc.
MIC2794
Bill of Materials
Item
Part Number
06036D105KAT2A
C1
GRM188R61C105KA93D
C1608X7R0J105KT
0603D184KAT2A
C2
GRM188R71C184KA01D
C1608X7R0J184KA93D
Manufacturer
Description
Qty.
(9)
AVX
Murata(10)
Capacitor, 1µF, 16V, X7R, 0603
1
Capacitor, 180nF,16V, X7R, 0603
1
(11)
TDK
AVX
Murata
TDK
R1
ERJ-3GEYJ104V
Panasonic(12)
Resistor, 100kΩ, 1/10W, 5%, 0603
1
U1
MIC2794x-xxVMT
MIC2794x-xxVD6
Micrel, Inc.(13)
Supervisor with Fast Propagation Delay and CapacitorProgrammable Reset Delay
1
Notes:
9. AVX: www.avx.com.
10. Murata: www.murata.com.
11. TDK: www.tdk.com.
12. Panasonic: industrial.panasonic.com
13. Micrel, Inc.: www.micrel.com.
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
PCB Layout Recommendations
Top Layer
Bottom Layer
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Package Information(14) and Recommended Land Pattern (TSOT-6)
6-Pin TSOT (D6)
Note:
14. Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com.
May 12, 2015
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Revision 1.2
Micrel, Inc.
MIC2794
Package Information(14) and Recommended Land Pattern (1.6mm × 1.6mm TDFN-6)
6-Pin 1.6mm × 1.6mm TDFN (MT)
May 12, 2015
14
Revision 1.2
Micrel, Inc.
MIC2794
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
Micrel, Inc. is a leading global manufacturer of IC solutions for the worldwide high performance linear and power, LAN, and timing & communications
markets. The Company’s products include advanced mixed-signal, analog & power semiconductors; high-performance communication, clock
management, MEMs-based clock oscillators & crystal-less clock generators, Ethernet switches, and physical layer transceiver ICs. Company
customers include leading manufacturers of enterprise, consumer, industrial, mobile, telecommunications, automotive, and computer products.
Corporation headquarters and state-of-the-art wafer fabrication facilities are located in San Jose, CA, with regional sales and support offices and
advanced technology design centers situated throughout the Americas, Europe, and Asia. Additionally, the Company maintains an extensive network
of distributors and reps worldwide.
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this datasheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical
implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2015 Micrel, Incorporated.
May 12, 2015
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