EM MICROELECTRONIC
-MARIN SA
Reset Circuit with Adjustable Delay
Description
The EM6354 is an ultra-low current reset circuit available in a
large variety of configurations and very small packages for
maximum flexibility in all end-applications up to 125°C and
using power supplies between 1.5V and 5.5V.
This circuit monitors the supply voltage of any electronic
system, and generates the appropriate reset signal. The
threshold defines the minimum allowed voltage which
guarantees the good functionality of the system. When V
DD
rises above V
TH
, the output remains active for an additional
delay time. This allows the system to stabilize before going
fully active. This delay time, or reset timeout period, can be
adjusted using an external capacitor.
The output is guaranteed to be in the correct state for V
DD
down to 0.8V. There are 11 reset threshold voltages starting
as low as 1.31V and up to 4.63V. The EM6354 features
three output types: active-low push-pull, active-low open-
drain and active-high push-pull.
Small SC70 and SOT23 packages as well as ultra-low
supply current of 2.9μA make the EM6354 an ideal choice
for portable and battery-operated devices.
EM6354
Features
Adjustable reset timeout period using an external
capacitor
Ultra-low supply current of 2.9μA (V
DD
=3.3V)
Operating temperature range: -40°C to +125°C
±1.5%
reset threshold accuracy
11 reset threshold voltages V
TH
: 4.63V, 4.4V, 3.08V,
2.93V, 2.63V, 2.2V, 1.8V, 1.66V, 1.57V, 1.38V, 1.31V
3 reset output options:
Active-low
RESET
push-pull
Active-low
RESET
open-drain
Active-high
RESET
push-pull
Immune to short negative V
DD
transients
Guaranteed Reset valid down to 0.8V
Threshold hysteresis: 2.1% of V
TH
Very small SOT23-5L and SC70-4L (SC-82AB)
packages
Typical Application
V
DD
V
DD
RESET
Applications
*
V
DD
RESET
EM6354
C
D
GND
MPU, DSP
GND
GND
*
R
EXT
for open-drain version only
Home appliances
Modems
Routers, hubs and gateways
WAN, LAN
Handheld GPS
Metering and Instrumentation
TV sets
Automotive systems
Block Diagram
V
DD
Voltage
Reference
1
2
4
3
GND
Pin Configuration
(top view)
RESET
(RESET)
V
DD
GND
1
2
3
4 NC
5
C
D
RESET
(RESET)
V
DD
-
+
Delay
Circuit
RESET
(RESET)
C
D
SOT23-5L
SC70-4L
(SC-82AB)
GND
C
D
Pin Description
Pin
SOT23-5L
SC70-4L
Name
RESET
Function
1
2
3
4
5
1
RESET
2
4
-
3
V
DD
GND
N.C.
C
D
Active-low RESET output. RESET remains low for the reset timeout period after all reset
conditions are deasserted and then goes high.
Active-high RESET output. RESET remains high for the reset timeout period after all reset
conditions are deasserted and then goes low.
Supply Voltage (5.5V max.)
Ground
Not connected. Not internally connected
Connect a capacitor between C
D
and GND to set the timeout period
(C
D
min=1nF; C
D
max=10000nF). Reset Timeout Period in [ms] is equal to C
D
in [nF]
Copyright
©
2006, EM Microelectronic-Marin SA
09/06 – rev.J
1
www.emmicroelectronic.com
EM6354
Ordering Information
EM6354 X SP5B - 2.9 +
Reset Output Type:
X = Active-low /RES push-pull
Y = Active-low /RES open-drain
Z = Active-high RES push-pull
RoHS Compliance:
+ = lead-free/green mold compliant
[blank]
= leaded
Reset Threshold Voltage (V
TH
):
1.3 = 1.31V
2.6 = 2.63V
1.4 = 1.38V
2.9 = 2.93V
1.6 = 1.57V
3.1 = 3.08V
1.7 = 1.66V
4.4 = 4.40V
1.8 = 1.80V
4.6 = 4.63V
2.2 = 2.20V
Package:
SP5B = SOT23-5, Tape&Reel 3000 pcs
SC4B = SC70-4, Tape&Reel 3000 pcs
Note:
subject to availability (see standard versions list below). Please give complete Part Number when ordering.
Standard Versions (Top Marking)
Part Number
Top
Top Marking
1)
Marking
with 4
Characters
2)
Part Number
Top
Top Marking
1)
Marking
with 4
Characters
2)
EM6354XSP5B-1.3
EM6354XSP5B-1.8
EM6354XSP5B-1.8+
EM6354XSP5B-2.6
EM6354XSP5B-2.9
EM6354XSP5B-2.9+
EM6354XSP5B-4.6
EM6354XSC4B-1.3
EM6354XSC4B-1.8
EM6354XSC4B-2.6
EM6354XSC4B-2.6+
EM6354XSC4B-2.9
EM6354XSC4B-4.6
EM6354XSC4B-4.6+
EM6354YSP5B-2.6
EM6354YSP5B-4.4
1)
2)
KC##
KA##
K4##
KB##
AMAA
AMAE
BMAE
AMAG
AMAH
BMAH
AMAL
AMAA
AMAE
AMAG
BMAG
AMAH
AMAL
BMAL
AMAT
AMAW
EM6354YSP5B-4.6
EM6354YSP5B-4.6+
EM6354XSP5B-1.3
EM6354XSP5B-1.8
EM6354XSP5B-2.6
EM6354XSP5B-2.9
K1##
AMAX
BMAX
AMAA
AMAE
AMAG
AMAH
Top marking is the 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.
Standard Versions (samples)
Part Number
EM6354XSC4B-2.6+
EM6354XSC4B-4.6
Part Number
EM6354XSP5B-2.9+
EM6354YSP5B-4.6+
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
©
2006, EM Microelectronic-Marin SA
09/06 – rev.J
2
www.emmicroelectronic.com
EM6354
Absolute Maximum Ratings
Parameter
Symbol
Conditions
Voltage at V
DD
to GND
V
DD
-0.3V to +6V
Minimum voltage at any signal
V
MIN
GND - 0.3V
pin
Maximum voltage at any signal
V
MAX
V
DD
+ 0.3V
pin
Electrostatic discharge max. to
MIL-STD-883C method 3015.7
V
ESD
2000V
with ref. to V
SS
Max. soldering conditions
T
MAX
250°C x 10s
Storage Temperature Range
T
STG
-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.
Handling Procedures
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 (note 1)
Operating Temperature
Symbol Min Max Unit
V
DD
0.8 5.5
V
T
A
-40 +125 °C
Electrical Characteristics
Unless otherwise specified: V
DD
= 0.8V to 5.5V, T
A
=+25°C (note 1).
Parameter
Symbol
Conditions
+25°C
V
DD
=1.5V
-40°C to +125°C
Supply current (note 2)
I
DD
V
DD
=3.3V
V
DD
=5.0V
+25°C
-40°C to +125°C
+25°C
-40°C to +125°C
Min
-
-
-
-
-
-
1.290
1.359
1.546
1.635
1.773
2.167
2.591
2.886
3.034
4.334
4.561
Typ
2.3
2.9
3.4
1.31
1.38
1.57
1.66
1.80
2.20
2.63
2.93
3.08
4.40
4.63
Max
4.6
7
5.5
8.3
6.3
9.6
1.330
1.401
1.594
1.685
1.827
2.233
2.669
2.974
3.126
4.466
4.699
Unit
μA
Threshold voltage
(note 3)
V
TH
EM6354 – 1.3
EM6354 – 1.4
EM6354 – 1.6
EM6354 – 1.7
EM6354 – 1.8
EM6354 – 2.2
EM6354 – 2.6
EM6354 – 2.9
EM6354 – 3.1
EM6354 – 4.4
EM6354 – 4.6
V
Threshold voltage
Δ
V
TH
temperature coefficient
-
-
ppm/°C
T
A
= -40°C to +125°C
±50
Δ
T
A
(note 4)
Threshold hysteresis
V
HYS
-
2.1%
•
V
TH
-
V
Note 1:
Production tested at +25°C only. Over temperature limits are guaranteed by design, not production tested.
V
DD
min=0.9V for active-high versions (EM6354Z).
Note 2:
RESET (RESET)
open.
Note 3:
Threshold voltage is specified for V
DD
falling.
Note 4:
Typical variation
ΔV
TH
of V
TH
at a given temperature T
A
is calculated as follows:
Δ
V
TH
(T
=
T
A
)
=
Δ
V
TH
×
V
TH
×
T
A
−
25
°
C
Δ
T
A
Example:
for version V
TH
=2.93V, variation at T
A
=70°C is equal to
ΔV
TH
(70°C)=±50
•
10
-6
x 2.93 x (70-25)=±6.59mV
Copyright
©
2006, EM Microelectronic-Marin SA
09/06 – rev.J
3
www.emmicroelectronic.com
EM6354
Electrical Characteristics
Parameter
Reset timeout period
Propagation delay time
V
DD
to
RESET
(RESET) delay
Open-drain
RESET
output
Voltage
(continued)
Unless otherwise specified: V
DD
= 0.8V to 5.5V, T
A
=+25° C (note 1).
Symbol
t
POR
t
P
V
OL
Conditions
C
D
=100nF (measured value, note 5)
V
DD
from 0V to V
TH (typ)
+15% (note 2)
EM6354-4.6 version
V
DD
drops from V
TH (typ)
+0.2V to V
TH (typ)
-0.2V
(note 2)
-40°C to +125°C
V
DD
>1V
V
DD
>2.5V
V
DD
>5V
V
DD
>1V
V
DD
>2.5V
V
DD
>5V
V
DD
>1V
I
OL
=100μA
I
OL
=1.5mA
I
OL
=3mA
I
OL
=100μA
I
OL
=1.5mA
I
OL
=3mA
Min
72
2
-
-
-
-
-
-
Typ
100
130
-
-
-
-
-
-
Max
122
255
0.3
0.3
0.3
0.3
0.3
0.3
Unit
ms
μs
V
V
OL
Push-pull RESET /
RESET
Output voltage
-40°C to +125°C
V
0.8
-
-
I
OH
=-30μA
-40°C to +125°C
V
OH
I
OH
=-1.5mA
2
-
-
V
DD
>2.5V
I
OH
=-3mA
4
-
-
V
DD
>5V
Output leakage current
I
LEAK
-40°C to +125°C, only for EM6354Y (open-drain)
-
-
0.5
μA
Note 1:
Production tested at +25°C only. Over temperature limits are guaranteed by design, not production tested.
V
DD
min=0.9V for active-high version (EM6354Z).
Note 2:
RESET
(RESET)
open.
Note 5:
t
POR
is programmable by varying the value of the external capacitor connected to pin C
D
. The relation is t
POR
(ms) =
C
D
(nF). The tolerance of the capacitor should be taken into account.
Timing Waveforms
t
SEN
V
DD
V
TH
Overdrive
V
HYS
0.8V
t
logic "1"
RESET
logic "0"
t
logic "1"
t
POR
t
P
RESET
RESET
logic "0"
t
Note 6:
t
SEN
= Maximum Transient Duration. Please refer to figure on the next page.
Note 7:
Overdrive = V
TH
-V
DD
. Please refer to figure on the next page.
Copyright
©
2006, EM Microelectronic-Marin SA
09/06 – rev.J
4
www.emmicroelectronic.com
EM6354
Typical Reset Timeout Period
The Reset Timeout Period (t
POR
) is programmable using an external capacitor connected to pin C
D
of EM6354. A ceramic
chip capacitor rated at or above 10V is sufficient. The Reset Timeout Period (t
POR
) can be calculated using the following
formula for V
TH
=4.63V (EM6354-4.6):
t
POR
(ms) = C
D
(nF).
For example a C
D
of 100nF will achieve a t
POR
of 100 ms. The tolerance of the capacitor should be taken into account. If no
delay due to t
POR
is needed in a certain application, the circuit EM6352 should be used instead.
For threshold voltage between V
TH
=4.63V and V
TH
=1.31V , the following graphic applies :
130
120
[ ms ]
110
100
1.31
2.93
V
TH
4.63
Typical Reset Timeout Period t
POR
vs. V
TH
for C
D
=100nF at T
A
=+25°C
[ms]
10000
VTH = 1.31 V
1000
VTH = 4.63 V
100
10
1
1
10
100
1000
10000
[nF]
Reset Timeout Period t
POR
vs. Capacitor C
D
at T
A
=+25°C
Copyright
©
2006, EM Microelectronic-Marin SA
09/06 – rev.J
5
www.emmicroelectronic.com
