MIC2774
Dual Micro-Power Low Voltage Supervisor
General Description
The MIC2774 is a dual power supply supervisor that
provides undervoltage monitoring, manual reset capability,
and power-on reset generation in a compact 5-pin SOT-23
package. Features include two undervoltage detectors,
one fixed and one adjustable, and a choice of reset
outputs. One undervoltage detector compares V
DD
against
a fixed threshold. Ten factory-programmed thresholds are
available. The second, user-adjustable input is compared
against a 300mV reference. This low reference voltage
allows for the monitoring of voltages lower than those
supported by previous supervisor ICs.
The reset outputs are asserted at power-on and at any
time either voltage drops below the programmed threshold
voltage and remains asserted for 140ms (min.) after they
subsequently rise back above the threshold boundaries.
Manual reset functionality can be provided by a switch
connected between ground and the /MR input. A wide
choice of voltage thresholds provides for a variety of
supply voltages and tolerances. Hysteresis is included to
prevent chattering due to noise. Typical supply current is a
low 3.5µA.
Datasheets and support documentation are available on
Micrel’s website at:
www.micrel.com.
Features
•
Monitors two independent power supplies for
undervoltage conditions
•
One fixed and one user-adjustable input
•
Choice of ten factory-programmed thresholds
•
Adjustable input can monitor supplies as low as 0.3V
•
Generates 140ms (min.) power-on reset pulse
•
Manual reset input
•
Choice of active-high, active-low, or open-drain active-
low reset outputs
•
Inputs may be pulled above V
DD
(7V abs. max.)
•
/RST output valid down to 1.2V
•
Ultra-low supply current, 3.5µA typical
•
Rejects brief input transients
•
IttyBitty™ 5-pin SOT-23 package
•
Pin-compatible upgrade for MAX6306/09/12
Applications
•
Monitoring processor ASIC or FPGA core and I/O
voltages
•
PDAs, hand-held PCs
•
Embedded controllers
•
Telecommunications systems
•
Power supplies
•
Wireless/cellular systems
•
Networking hardware
Typical Application
IttyBitty is a trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 •
http://www.micrel.com
March 16, 2015
Revision 2.0
Micrel, Inc.
MIC2774
Ordering Information
Part Number
(1,2)
Marking
(1,3)
Reset Output
Open-Drain. Active-Low (/RST)
Active-High. Complementary (RST)
Active-Low. Complementary (/RST)
Junction Temperature Range
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
Package
(4)
MIC2774N-XXYM5
MIC2774H-XXYM5
MIC2774L-XXYM5
Note:
UGXX
UHXX
UIXX
SOT-23-5
SOT-23-5
SOT-23-5
1. XX = voltage code, see table below.
2. Order entry part number, add “ TR”. Example: MIC2774N-22YM5 TR.
3. Underbar symbol (__) may not be to scale.
4. Standard reel SOT-23: Reel diameter is 7 inches, hub diameter is 2 inches, width is 8mm.
Standard Voltage Options
(5)
Voltage Code
46
44
31
29
28
26
25
23
22
17
Note:
5. There are ten standard versions available with an order increment of 3,000 pieces. Samples of standard versions are normally available from stock.
Contact factory for information on non-standard versions. Available in tape-and-reel only.
Typical Application (V
DD
)
5.0V ±5%
5.0V ±10%
3.3V ±5%
3.3V ±10%
3.0V ±5%
2.85V ±5%
2.7V ±5%
2.5V ±5%
2.4V ±5%
1.8V ±5%
Nominal Threshold Voltage (V
TH
)
4.68V
4.43V
3.09V
2.93V
2.81V
2.67V
2.53V
2.34V
2.25V
1.69V
Part Number Convention
March 16, 2015
2
Revision 2.0
Micrel, Inc.
MIC2774
Pin Configuration
SOT-23-5 (M5)
“H” Version
SOT-23-5 (M5)
“L” and “N” Version
Pin Description
Pin Number
MIC2774H
Pin Number
MIC2774L
MIC2774N
Pin Name
Pin Function
Digital (Output): Asserted high whenever V
IN
or V
DD
falls below the threshold
voltage. It will remain asserted for no less than 140ms after V
IN
and V
DD
return
above the threshold limits.
Digital (Output): Asserted low whenever V
IN
or V
DD
falls below the threshold
voltage. It will remain asserted for no less than 140ms after V
IN
and V
DD
return
above the threshold limits. (Open-drain for “N” version, requires an external
pull-up resistor).
Ground
Digital (Input): Driving this pin low initiates immediate and unconditional reset.
Assuming V
IN
and V
DD
are above the thresholds when /MR is released
(returns high), the reset output will be de-asserted no less than 140ms later.
/MR may be driven by a logic signal or a mechanical switch. /MR has an
internal pull-up to V
DD
and may be left open if unused.
Analog (Input): The voltage on this pin is compared to the internal 300mV
reference. An undervoltage condition will trigger a reset sequence.
Analog (Input): Power supply input for internal circuitry and input to the fixed
voltage monitor. The voltage on this pin is compared against the internal
reference. An undervoltage condition will trigger a reset sequence.
1
RST
1
/RST
2
2
GND
3
3
/MR
4
4
IN
5
5
VDD
March 16, 2015
3
Revision 2.0
Micrel, Inc.
MIC2774
Absolute Maximum Ratings
(6)
Supply Voltage (V
DD
) .................................... –0.3V to +7.0V
Input Voltages (V
IN
, V
/MR
) ............................. –0.3V to +7.0V
Output Voltages (V
/RST
, V
RST
) ....................... –0.3V to +7.0V
RST, (/RST) Current ................................................... 20mA
Storage Temperature (Ts)......................... –65°C to +150°C
(8)
ESD Rating ............................................................... 1.5kV
Operating Ratings
(7)
Supply Voltage (V
DD
) .................................... +1.5V to +5.5V
Input Voltages (V
IN
, V
/MR
) ............................. –0.3V to +6.0V
Output Voltages
V
/RST
(N version) .................................... –0.3V to +6.0V
V
/RST
, V
RST
(H and L versions) .... –0.3V to V
DD
to +0.3V
Ambient Temperature (T
A
) .......................... –40°C to +85°C
Package Thermal Resistance (θ
JA
) ........................ 256°C/W
Electrical Characteristics
(9)
Note 10;
T
A
= +25°C,
bold
values indicate –40°C≤ T
A
≤ +85°C, unless noted.
Symbol
I
DD
Parameter
Supply Current
Condition
V
DD
= V
IN
= V
TH
+ 1.6%;
Note 10;
/MR, RST, /RST open
Min.
Typ.
3.5
Max.
Units
µA
VDD Voltage Threshold
Undervoltage Threshold on V
DD
(See
Standard Voltage Options
table)
V
HYST
Hysteresis Voltage
V
TH
-
1.5%
V
TH
1
V
TH
+
1.5%
V
%
IN, Undervoltage Detector Input
V
REF
V
HYST
I
IN
Undervoltage Threshold
Hysteresis Voltage
Input Current
T
MIN
≤ T
A
≤ T
MAX
V
IN
= (V
REF(MAX)
+ 100mV) to
V
IN
= (V
REF(MIN)
– 100mV), /MR = open
T
MIN
≤ T
A
≤ T
MAX
I
SINK
= 1.6mA; V
DD
≥ 1.6V
I
SINK
= 100µA; V
DD
≥ 1.2V;
Note 11
I
SOURCE
= 500µA; V
DD
≥ 1.5V
I
SOURCE
= 10µA; V
DD
≥ 1.2V;
Note 11
0.8 ×
V
DD
0.8 ×
V
DD
140
Note 10
295
300
3
5
10
305
mV
mV
pA
nA
RST, /RST Outputs
t
PROP
t
RST
V
OL
Propagation Delay
Reset Pulse Width
RST or /RST Output Voltage
Low
20
280
0.3
0.3
µs
ms
V
V
V
V
V
OH
RST or /RST Output Voltage
High (H and L versions)
Notes:
6. Exceeding the absolute maximum ratings may damage the device.
7. The device is not guaranteed to function outside its operating ratings.
8. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.
9. Specification for packaged product only
10. V
DD
equals nominal “Typical Application (V
DD
)” as shown in the
Standard Voltage Options
table.
11. V
DD
operating range is 1.5V to 5.5V. Output is guaranteed to be asserted down to V
DD
= 1.2V.
March 16, 2015
4
Revision 2.0
Micrel, Inc.
MIC2774
Electrical Characteristics
(9)
Note 10;
T
A
= +25°C,
bold
values indicate –40°C≤ T
A
≤ +85°C, unless noted.
Symbol
/MR Inputs
V
IH
V
IL
t
PROP
t
MIN
I
PU
I
IN
Input High Voltage
Input Low Voltage
Propagation Delay
Minimum Input Pulse Width
Internal Pull-Up Current
Input Current, /MR
V
/MR
< V
IL
Note 10
Note 10
V
/MR
< (V
IL
– 100mV);
Note 10
Reset occurs, V
/MR
< V
IL
5
33
100
100
250
250
0.7 ×
V
DD
0.3 ×
V
DD
V
%
µs
ns
nA
nA
Parameter
Condition
Min.
Typ.
Max.
Units
Timing Diagram
Notes:
12. Propagation delays not shown for clarity.
13. The MIC2774 ignores very brief transients. See the
Application Information
section for details.
March 16, 2015
5
Revision 2.0
stm32/stm8
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