MIC2774_05 Datasheet, PDF (1/8 Pages) Micrel Semiconductor – Dual Micro-Power Low Voltage Supervisor

MIC2774
Dual Micro-Power Low Voltage Supervisor
General Description
Features
The MIC2774 is a dual power supply supervisor that pro-
vides under-voltage monitoring, manual reset capability, and
power-on reset generation in a compact 5-pin SOT package.
Features 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
factory-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 con-
nected 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.
Ordering Information
• Monitors two independent power supplies for under-volt-
age 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 volt-
ages
• PDAs, hand-held PCs
• Embedded controllers
• Telecommunications systems
• Power supplies
• Wireless / Cellular systems
• Networking hardware
Part Number
Standard
Marking Pb-Free
Marking
Reset Output
Temperature Package
Range
MIC2774N-XXBM5
MIC2774H-XXBM5
MIC2774L-XXBM5
UGXX⁽¹⁾
UHXX⁽¹⁾
UIXX⁽¹⁾
MIC2774N-XXYM5
MIC2774H-XXYM5
MIC2774L-XXYM5
UGXX⁽¹⁾
UHXX⁽¹⁾
UIXX⁽¹⁾
Open-Drain. Active-Low (/RST)
Active-High. Complementary (RST)
Active-Low. Complementary (/RST)
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
SOT-23-5
SOT-23-5
SOT-23-5
Notes:
1.
XX = Voltage options, see table on page 2. Underscore indicates a Pb-Free part.
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. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
October 2005
1
M9999-102605