MIC2774N-26YM5 TR Micrel Inc, MIC2774N-26YM5 TR Datasheet - Page 5

• Manufacturer Part Number: MIC2774N-26YM5 TR
• Description: Dual Ultra-Low-V Supervisor
• Manufacturer: Micrel Inc
• Type: Multi-Voltage Supervisorr

Specifications of MIC2774N-26YM5 TR

• Active-high: Manual Reset, SOT23-5 ( )
• Number Of Voltages Monitored: 2
• Output: Open Drain or Open Collector
• Reset: Active Low
• Reset Timeout: 140 ms Minimum
• Voltage - Threshold: 2.67V, Adj
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SOT-23-5, SC-74A, SOT-25
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MIC2774N-26YM5TR; MIC2774N-26YM5TR

Functional Diagram
Functional Description
IN, Under-Voltage Detector Input
The voltage present at the IN pin is compared to the internal
300mV reference voltage. A reset is triggered if and when V
falls below V
the input voltage to be monitored such that V
V
trip-point. Hysteresis is employed to prevent chattering due
to noise. The comparator on the IN pin is relatively immune
to very brief negative-going transients.
V
The V
input voltage. The voltage at this pin is continually compared
against the internal reference. The trip-point at which a reset
occurs is factory programmed. A reset is triggered if and
when V
to prevent chattering due to noise. The comparator on the
V
transients.
RST, /RST Reset Output
Typically, the MIC2774 is used to monitor the power supplies
of intelligent circuits such as microcontrollers and micropro-
cessors. By connecting the appropriate reset output of a
October 2005
REF
DD
DD
Input
input is relatively immune to very brief negative-going
as the voltage being monitored falls below the desired
DD
DD
pin is both the power supply terminal and a monitored
falls below the trip-point. Hysteresis is employed
REF
. Typically, a resistor divider is used to scale
/MR
V
IN
DD
V
* Pinout andpolarity vary by device type.
See ordering inf
DD
I
PU
ing inf
ing in o fo f rmation tabl e
GND
V
V
REF
REF
tion tabl e
tion tabl .
IN
will fall below
IN
5
MIC2774 to the reset input of a µC or µP, the processor will
be properly reset at power-on and during power-down and
brown-out conditions. In addition, asserting /MR, the manual
reset input, will activate the reset function.
The reset output is asserted any time /MR is asserted or if V
or V
reset output remains asserted for t
V
and/or /MR is released. A reset pulse is also generated at
power-on. Hysteresis is included in the comparators to prevent
chattering of the output due to noise.
/MR, Manual Reset Input
The ability to initiate a reset via external logic or a manual
switch is provided in addition to the MIC2774’s automatic
supervisory functions. Driving the /MR input to a logic low
causes an immediate and unconditional reset to occur.
Assuming V
released (returns high), the reset output will be de-asserted
no less than t
or mechanical switch. Typically, a momentary push-button
switch is connected such that /MR is shorted to ground when
the switch contacts close. Switch de-bouncing is performed
internally; the switch may be connected directly between
/MR and GND. /MR is internally pulled-up to V
be left open if unused.
DD
Delay
Line
Line
DD
subsequently return above the threshold boundaries
drops below the corresponding threshold voltage. The
One Shot
IN
RST
and V
later. /MR may be driven by a logic signal,
DD
R R
S S
MIC2774
are within tolerance when /MR is
/Q /Q
Q Q
RST
/RST*
RST*
(min) after V
DD
M9999-102605
IN
and may
and/or
IN