EM MICROELECTRONIC - MARIN SA
EM6323-6324
Reset Circuit with Manual Reset and Watchdog
Description
Features
The EM6323/24 are low power, high precision reset ICs
featuring a manual reset and a watchdog inputs. They have
different threshold voltages and several timeout reset periods
(tPOR) and watchdog timeout periods (tWD) for maximum
flexibility in the application. EM6323 has a manual reset ( MR
with internal pull-up) and a watchdog input pins. EM6324 has
only a watchdog input pin (WDI). The watchdog function can
be disabled by driving WDI with a three-state driver or by
leaving WDI unconnected. This is useful when the MCU is in
sleep mode.
Small SOT23-5L package as well as ultra-low supply current
of 3.8μA make the EM6323 and the EM6324 an ideal choice
for portable and battery-operated devices.
Ultra-low supply current of 3.8μA (VDD=3.3V)
Operating temperature range: -40°C to +125°C
1.5% reset threshold accuracy
11 reset threshold voltages VTH: 4.63V, 4.4V, 3.08V,
2.93V, 2.8V, 2.63V, 2.3V, 2.2V, 2.0V, 1.8V, 1.66V,
1.57V, 1.38V, 1.31V
200ms reset timeout period (1.6ms, 25ms, 1600ms on
request)
1.6s watchdog timeout period (6.2ms, 102ms, 25.6s on
request)
3 reset output options:
Active-low RESET push-pull
Typical Application
Active-low RESET open-drain
VDD
VDD
*
VDD
RESET
RESET
RESET
RESET
EM632x
MR
Applications
MPU, DSP
WDI
Active-high RESET push-pull
Detection of microcontroller in sleep mode
I/O
GND
GND
GND
* REXT for open-drain version only
Fig. 1
Workstations
Point of sales (POS)
Personal computers
Routers, hubs and switches
Handheld GPS
Vending machines and ATM
VDD
Pin Configuration
Voltage
Reference
MR
-
Reset
Logic
+ Timer
EM6323
RESET
RESET
Filter
GND
Transition
Detector
WDI
Watchdog Logic
+ Timer
RESET
1
GND
2
MR
3
(manual reset,
watchdog)
SOT23-5
5
4
VDD
WDI
top view
EM6324
RESET
push-pull/open-drain
1
GND
2
RESET
3
(watchdog)
EM6324
+
EM6323
Oscillator
5 VDD
4
WDI
push-pull
SOT23-5
top view
Fig. 3
Block Diagram
Fig. 2
Pin Description
SOT23-5L
EM6323 EM6324
Name
1
1
RESET
2
2
GND
3
-
MR
-
3
RESET
4
4
WDI
5
5
VDD
Function
Active-low RESET output (push-pull or open-drain)
Ground
Manual Reset input with an internal pull-up 30k resistor. Reset remains active as long as MR is low
and for tPOR after returns high. MR can be driven with a CMOS output or shorted to ground with a switch
Active-high RESET output (push-pull)
Watchdog input. WDI must be driven with a CMOS output. If the microcontroller I/O is put in a high
impedance condition, the circuit will detect this condition as a microcontroller in sleep mode and prevent
its watchdog from timing out
Supply Voltage (5.5V max.)
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
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EM6323-6324
Ordering Information
EM6323 L X SP5B - 2.9 +
Part Number:
EM6323 = manual reset & watchdog
EM6324 = watchdog
RoHS Compliance:
+ = lead-free/green mold compliant
[blank] = leaded
Delays tPOR & t WD :
Reset Threshold Voltage:
= 1.31V 1.8 = 1.80V 2.6 = 2.63V 4.4 = 4.40V
= 1.38V 2.0 = 2.00V 2.8 = 2.80V 4.6 = 4.63V
= 1.57V 2.2 = 2.20V 2.9 = 2.93V
= 1.66V 2.3 = 2.30V 3.1 = 3.08V
t POR [ms]
1.6 25 200 1600
B
C
D
6.2 A
F
G
H
102 E
K
L
M
1600 J
P
Q
R
25600 N
("L" is the standard version")
1.3
1.4
1.6
1.7
tWD [ms]
EM6323/24:
Package:
SP5B
= 5-pin SOT23-5, tape&reel, 3000 pcs
Reset Output Type:
X
(Active-high RESET push-pull also for EM6324)
= Active-low /RESET push-pull
Y
(Active-high RESET push-pull also for EM6324)
= Active-low /RESET open-drain
Z
= Active-high RESET push-pull (EM6323 only)
Note:
subject to availability (see standard versions list below). Please give complete Part Number when ordering
Standard Versions (Top Marking)
1)
2)
Delay (tPOR)/
Threshold
Voltage
Watchdog timer (tWD)
2.63V
200ms/1600ms
Top
Top Marking
with 4
Marking 1)
characters 2)
Output Type
Package
Part Number
Active-low push-pull RESET
SOT23-5L
EM6323LXSP5B-2.6+
KF##
BPLG
EM6323LXSP5B-2.9+
K0##
BPLH
2.93V
200ms/1600ms
Active-low push-pull RESET
SOT23-5L
2.93V
200ms/1600ms
Active-low open-drain RESET
SOT23-5L
EM6323LYSP5B-2.9+
K6##
BPLU
4.40V
200ms/1600ms
Active-low push-pull RESET
SOT23-5L
EM6324LXSP5B-4.4+
K9##
BQMK
2.93V
25ms/1600ms
Active-low open-drain RESET
SOT23-5L
EM6324KYSP5B-2.9+
KL##
2.8V
200ms/25600ms
Active-low open-drain RESET
SOT23-5L
EM6324QYSP5B-2.8+
KK##
Top marking is standard from 2006. No bottom marking exists. Where ## refers to the lot number (EM internal reference
only)
Top marking with 4 characters is standard from 2003. For lead-free/green mold (RoHS) parts, the first letter of top
marking with 4 characters begins with letter “B” instead of letter “A”. Bottom marking indicates the lot number.
Sample stock is generally held on standard versions only. Please contact factory for other versions not shown here and
for availability of non standard versions.
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
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EM6323-6324
Absolute Maximum Ratings
Parameter
Handling Procedures
Symbol
Conditions
Voltage at VDD to GND
Minimum voltage at any signal pin
Maximum voltage at any signal pin
VDD
VMIN
VMAX
-0.3V to +6V
GND - 0.3V
VDD + 0.3V
Electrostatic discharge max. to
MIL-STD-883C method 3015.7
with ref. to VSS
VESD
2000V
Max. soldering conditions
Storage Temperature Range
TMAX
TSTG
250°C x 10s
-65°C to +150°C
Stresses above these listed maximum ratings may
cause permanent damages to the device. Exposure
beyond specified operating conditions may affect device
reliability or cause malfunction.
This device has built-in protection against high static
voltages or electric fields; however, anti-static
precautions must be taken as for any other CMOS
component. Unless otherwise specified, proper
operation can only occur when all terminal voltages are
kept within the voltage range. Unused inputs must
always be tied to a defined logic voltage level.
Operating Conditions
Parameter
Supply voltage
Operating Temperature
Input transition rise and fall rate
on MR and WDI
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
3
Symbol Min Max Unit
VDD
TA
tR/tF
0.9 5.5
V
-40 +125 °C
-
100 ns/V
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EM6323-6324
Electrical Characteristics
Unless otherwise specified: VDD= 0.9V to 5.5V, TA=-40°C to +125°C (note 1).
Parameter
Symbol
Conditions
Min
+25°C
-40°C to +125°C
+25°C
-40°C to +125°C
+25°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
+25°C
-40°C to +85°C
-40°C to +125°C
1.290
1.245
1.221
1.359
1.311
1.286
1.546
1.492
1.463
1.635
1.577
1.547
1.773
1.710
1.678
1.970
1.900
1.864
2.167
2.090
2.050
2.266
2.185
2.144
2.591
2.499
2.451
2.758
2.660
2.610
2.886
2.784
2.731
3.034
2.926
2.871
4.334
4.180
4.101
4.561
4.399
4.315
VDD=1.5V
Supply current (note 2)
IDD
VDD=3.3V
VDD=5.0V
EM6323/24 – 1.3
EM6323/24 – 1.4
EM6323/24 – 1.6
EM6323/24 – 1.7
EM6323/24 – 1.8
EM6323/24 – 2.0
EM6323/24 – 2.2
Threshold voltage
(note 3)
VTH
EM6323/24 – 2.3
EM6323/24 – 2.6
EM6323/24 – 2.8
EM6323/24 – 2.9
EM6323/24 – 3.1
EM6323/24 – 4.4
EM6323/24 – 4.6
Typ
2.4
3.86
5.89
1.31
1.38
1.57
1.66
1.80
2.00
2.20
2.30
2.63
2.8
2.93
3.08
4.40
4.63
Max
4.4
6.8
6.1
9.9
8.6
11.6
1.330
1.382
1.387
1.401
1.456
1.461
1.594
1.656
1.663
1.685
1.751
1.758
1.827
1.899
1.906
2.030
2.110
2.118
2.233
2.321
2.330
2.335
2.427
2.436
2.669
2.775
2.785
2.842
2.954
2.965
2.974
3.091
3.103
3.126
3.249
3.262
4.466
4.642
4.660
4.699
4.885
4.903
Unit
A
V
Note 1: Production tested at +25°C only. Over temperature limits are guaranteed by design, not production tested.
Note 3: Threshold voltage is specified for VDD falling.
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
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EM6323-6324
Electrical Characteristics (continued)
Unless otherwise specified: VDD= 0.9V to 5.5V, TA=-40°C to +125° C (note 1).
Parameter
Threshold hysteresis
Reset timeout period
Symbol
Conditions
Min
Typ
Max
Unit
VHYS
TA=+25°C
-
2.1%VTH
-
V
tPOR
Propagation delay time
VDD to RESET (RESET)
delay
Open-drain RESET output
Voltage
tP
VOL
VOL
Push-pull RESET / RESET
Output voltage
VOH
Output leakage current
ILEAK
EM6323/24 C-G-L-Q
160
200
240
EM6323/24 A-E-J-N
0.7
1.56
3.8
EM6323/24 B-F-K-P
20
25
30
EM6323/24 D-H-M-R
1280
1600
1920
VDD drops from VTH (typ)+0.2V to VTH (typ)-0.2V
(note 2). TA= +25°C
2
70
255
VDD>1V
IOL=100A
-
-
0.3
VDD>2.5V
IOL=1.5mA
-
-
0.3
VDD>5V
IOL=3mA
-
-
0.35
VDD>1V
IOL=100A
-
-
0.3
VDD>2.5V
IOL=1.5mA
-
-
0.3
VDD>5V
IOL=3mA
-
-
0.35
VDD>1.1V
IOH=-30A
0.8
-
-
VDD>2.5V
IOH=-1.5mA
2
-
-
VDD>5V
IOH=-3mA
4
-
-
-
-
0.5
A
VDD from 0V to VTH (typ)+15%
TA= +25°C
(note 2 and 4)
Only for EM6323/24_Y (open-drain)
ms
s
V
V
WATCHDOG INPUT (WDI)
WDI Input low
VWDI low
WDI Input high
VWDI high
Pulse width at WDI
-
-
0.3VDD
V
0.7VDD
-
-
V
1
-
-
s
EM6323/24 J-K-L-M
1280
1600
1920
EM6323/24 A-B-C-D
5
6.25
7.5
EM6323/24 E-F-G-H
80
100
120
EM6323/24 N-P-Q-R
TA= +25°C
tWP
Watchdog timeout period
tWD
(note 6)
ms
20480
25600
30720
High-level Input Current
IIH
WDI connected to VDD, TA= +25°C
-
18
-
A
Low-level Input Current
IIL
WDI connected to GND, TA= +25°C
-
8.3
-
A
MANUAL RESET ( MR ) – EM6323 only
MR Input low
VMRT low
-
-
0.3VDD
V
MR Input high
VMRT high
0.7VDD
-
-
V
MR to Reset delay
tMD
Pulse width at MR (note 5)
tPMD
MR Internal Pull-up
resistor
RMR
TA= +25°C
TA=-40°C to +125°C
-
0.3
-
s
1
-
-
s
7
30
74
k
Note 1:
Note 2:
Note 3:
Note 4:
Production tested at +25°C only. Over temperature limits are guaranteed by design, not production tested.
WDI, MR and RESET (RESET) open.
Threshold voltage is specified for VDD falling.
Standard version for tPOR is 200ms (typ). Other option (1.6ms, 25ms, 1600ms) are available by mask option and
upon minimum order quantity. Please contact EM sales.
Note 5: Pulse width must be greater than 1s to ensure the RESET (RESET) to go active.
Note 6: Standard version for tWD is 1600ms (typ). Other option (6.2ms, 102ms, 25.6s) are available by mask option and
upon minimum order quantity. Please contact EM sales.
Copyright 2015, EM Microelectronic-Marin SA
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EM6323-6324
Timing Waveforms
tSEN
VDD
VHYS
VTH
Overdrive
0.9V
t
logic "1"
tPMD
MR
logic "0"
t
logic "1"
tPOR
RESET
tP
tMD
logic "0"
t
logic "1"
tPOR
RESET
logic "0"
t
Fig. 4
logic "1"
tWP
WDI
tWD
tWD
logic "0"
t
logic "1"
RESET
logic "0"
t
logic "1"
tPOR
RESET
logic "0"
t
Fig. 5
Note 7: tSEN = Maximum Transient Duration. Please refer to figure on the next page.
Note 8: Overdrive = VTH -VDD. Please refer to figure on the next page.
Copyright 2015, EM Microelectronic-Marin SA
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EM6323-6324
Typical Operating Characteristics
(Typical values are at TA=+25°C unless otherwise noted. WDI, MR , RESET and RESET open.)
9
6%
8
4%
VDD 5 . 0 V
7
2%
6
5
[ uA ]
4
0%
VDD 3 . 3 V
-2%
3
VDD 1. 5 V
2
-4%
1
0
-50
-6%
-25
0
25
50
[ °C ]
75
100
-50
125
-25
0
25
50
[ °C ]
75
100 125
Fig. 6
Fig. 7
IDD vs. Temperature
Threshold Voltage Variation vs. Temperature
(normalized)
160%
160%
tWD (°C)
tWD (25°C)
tPOR (°C)
140%
140%
tPOR (25°C)
120%
120%
100%
100%
80%
80%
60%
60%
-50
-25
0
25
50
[ °C ]
75
100
-50
125
0
25
50
[ °C ]
75
100
125
Fig. 9
Fig. 8
Watchdog Timeout Period tWD vs. Temperature
(normalized with respect to tWD 25°C)
Reset Timeout Period tPOR vs. Temperature
(normalized with respect to tPOR 25°C)
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
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EM6323-6324
Typical Operating Characteristics
(Typical values are at TA=+25°C unless otherwise noted. WDI, MR , RESET and RESET open.)
120
120
100
100
80
[ us ]
60
80
[ us ]
60
40
40
20
20
0
-50
Reset occurs above
this line
0
-25
0
25
50
[ °C ]
75
100
125
1
10
[ mV ]
100
1000
Fig. 10
Fig. 11
Propagation Time tPHL vs. Temperature
Maximum Transient Duration tSEN vs.
Overdrive VTH-VD
250
350
225
300
200
250
[ ns ]
[ ns ]
175
200
150
150
125
100
-50
-25
0
25
50
75
100
-50
100 125
[ °C ]
Fig. 12
0
25
50
[ °C ]
75
100
125
Fig. 13
Watchdog Input Pulse Width tWP vs. Temperature
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6323-6324-DSVersion 2.0, 2-Jun-15
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Manual Reset Pulse Width tPMD vs. Temperature
8
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EM6323-6324
Functional Description
VDD
MR
High Impedance
WDI
RESET
t < tWD
tPOR
t > tWD
tPOR
tPOR
Fig. 14
Reset Outputs
Manual Reset Input (EM6323 only)
A microprocessor (µP) reset input starts the µP in a
known state. The EM6323/24 µP supervisory circuits
assert a reset to prevent code-execution errors during
power-up, power-down, and brownout conditions. RESET
is guaranteed to be a logic low for VDD down to 0.9V.
Once VDD exceeds the reset threshold, an internal timer
keeps RESET low for the specified reset timeout period
(tPOR); after this interval, RESET returns high.
If a brownout condition occurs (VDD dips below the reset
threshold), RESET goes low. Each time RESET is
asserted it stays low for the reset timeout period. Any
time VDD goes below the reset threshold the internal
timer restarts. RESET is the inverse of RESET.
A logic low on MR asserts a reset. Reset remains
asserted while MR is low, and for tPOR (200ms nominal for
EM6323 C-G-L-Q) after it returns high. MR has an
internal 30k pull-up resistor, so it can be left open if
unused. This input can be driven with CMOS logic levels
or with open-drain outputs. Connect a normally open
momentary switch from MR to VSS to create a manualreset function; debounce circuitry is integrated. If MR is
driven from long cable or the device is used in a noisy
environment, connect a 0.1F capacitor from MR to VSS
to provide additional noise immunity (stronger external
additional pull-up resistor can also be added).
Copyright 2015, EM Microelectronic-Marin SA
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EM6323-6324
Watchdog Input
If the watchdog timer has not been cleared within tWD
(1.6s typ.), reset asserts. The internal 1.6s timer is
cleared by either a reset pulse or by toggling WDI. While
reset is asserted, the timer remains cleared and does not
count. As soon as reset is released, the timer starts
counting.
If the microcontroller I/O connected to WDI is put in a
high impedance condition, the circuit will detect this
condition as a microcontroller in sleep mode and prevent
its watchdog from timing out. To monitor a high
impedance or a three state condition on WDI, the
watchdog input is internally driven low during the first
15/16 of the watchdog timeout period and high for the
last 1/16 of the watchdog timeout period.
When WDI is left unconnected, this internal driver clears
the 1.6s timer every 1.5s. When WDI is three-stated or
unconnected, the maximum allowable leakage current is
0.5µA.
To minimized the overall system power consumption and
therefore for a minimum watchdog input current leave
WDI low for the majority of the watchdog timeout period,
pulsing it low-high-low once within the first 15/16 of the
watchdog timeout period to reset the watchdog timer. If
WDI is externally driven high for the majority of the
timeout period, up to 35µA can flow into WDI. Meanwhile
when the microcontroller is not in sleep mode, the output
of the microcontroller which drives WDI has to be strong
enough to fight the 35µA.
VDD
VDD
Pullup
RESET
1/16 tWD
WDI Pullup OFF
ON
OFF
WDI Pulldown ON
OFF
ON
tPOR
15/16 tWD
Transition
Detector
WDI
Watchdog Logic
+ Timer
15/16 tWD
1/16 tWD
Pulldown
tWD
GND
Fig. 16
Fig. 15
WDI Input Stage Block Schematic
WDI Input Timing Diagram
15.0
25.0
12.0
20.0
9.0
[ uA ]
[ uA ]
6.0
10.0
3.0
5.0
0.0
-50
15.0
0.0
-25
0
25
50
75
100
125
-50
[ °C ]
0
25
50
75
100 125
[ °C ]
Fig. 17
Fig. 18
WDI Input Current Low-level IIL vs. Temperature
(VDD=5.5V)
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6323-6324-DSVersion 2.0, 2-Jun-15
-25
WDI Input Current High-Level IIH vs. Temperature
(VDD=5.5V)
10
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EM6323-6324
Package Information
D
E1
SOT23-5L
C
A1 A2 A
b
E
e
SYM BOL
A
A1
A2
b
C
D
E
E1
e
e1
L
e1
M IN
0.90
0.05
0.90
0.35
0.08
2.80
2.60
1.50
L
TYP
1.30
0.08
1.15
2.90
2.80
M AX
1.45
0.15
1.30
0.50
0.20
3.00
3.00
1.75
0.95
1.90
0.45
Dimensions are in mm
Fig. 19
Traceability for small packages
Due to the limited space on the package surface, the bottom marking contains a limited number of characters that provide only partial
information for lot traceability. Full information for complete traceability is however provided on the packing labels of the product at
delivery from EM. It is highly recommended that the customer insures full lot traceability of EM product in his final product.
EM Microelectronic-Marin SA (“EM”) makes no warranties for the use of EM products, other than those expressly contained in EM's
applicable General Terms of Sale, located at http://www.emmicroelectronic.com. EM assumes no responsibility for any errors which may
have crept into this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does
not make any commitment to update the information contained herein.
No licenses to patents or other intellectual property rights of EM are granted in connection with the sale of EM products, neither expressly
nor implicitly.
In respect of the intended use of EM products by customer, customer is solely responsible for observing existing patents and other
intellectual property rights of third parties and for obtaining, as the case may be, the necessary licenses.
Important note: The use of EM products as components in medical devices and/or medical applications, including but not
limited to, safety and life supporting systems, where malfunction of such EM products might result in damage to and/or injury or
death of persons is expressly prohibited, as EM products are neither destined nor qualified for use as components in such
medical devices and/or medical applications. The prohibited use of EM products in such medical devices and/or medical
applications is exclusively at the risk of the customer.
Product qualification is performed according to internal EM quality standards for industrial products. For any special requirement (eg. automotive grade) please
contact EM Microelectronic-Marin S.A.
Copyright 2015, EM Microelectronic-Marin SA
6323-6324-DSVersion 2.0, 2-Jun-15
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