MIC2774 Datasheet, PDF (1/8 Pages) Micrel Semiconductor – Dual Micro-Power Low Voltage Supervisor Advance Information

MIC2774
Micrel
MIC2774
Dual Micro-Power Low Voltage Supervisor
Advance Information
General Description
The MIC2774 is a dual power supply supervisor that provides
under-voltage monitoring, manual reset capability, and power-
on reset generation in a compact 5-pin SOT package. Fea-
tures include two under-voltage detectors, one fixed and one
adjustable, and a choice of reset outputs. One under-voltage
detector compares V_DD against a fixed threshold. Ten fac-
tory-programmed thresholds are available. The second, user-
adjustable input is compared against a 300mV reference.
This low reference voltage allows monitoring voltages lower
than those supported by previous supervisor ICs.
The reset outputs are asserted at power-on and any time
either voltage drops below the programmed threshold volt-
ages 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.
Features
• Monitors two independent power supplies for under-
voltage conditions
• One fixed and one user adjustable input
• Choice of factory-programmed thresholds
• Adjustable input can monitor supplies as low as 0.3V
• Generates 140ms (minimum) 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.)
• Open-drain output can 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-lead SOT-23 package
• Pin compatible upgrade for MAX6306/09/12
Applications
• Monitoring processor ASIC, or FAGA core and I/O
voltages
• PDAs, hand-held PCs
• Embedded controllers
• Telecommunications systems
• Power supplies
• Wireless / Cellular systems
• Networking hardware
Ordering Information
Part Number
MIC2774N-XXBM5
MIC2774H-XXBM5
MIC2774L-XXBM5
Marking
UGXX
UHXX
UIXX
Reset Output
Temperature Range
Open-Drain, Active-Low (/RST)
–40°C to +85°C
Active-High, Complementary (RST) –40°C to +85°C
Active-Low, Complementary (/RST) –40°C to +85°C
Package
SOT-23-5
SOT-23-5
SOT-23-5
Typical Application
V_CORE 1.0V
V_I/O 2.5V
R1
R2
Power_Good
Manual
Reset
MIC2774L-23
VDD /RST
IN
/MR GND
MICROPROCESSOR
VCORE
VI/O
/RESET GND
IttyBitty™ is a trademark of Micrel, Inc.
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
September 29, 2000
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MIC2774