MICREL MIC2774H-XXBM5, MIC2774L-XXBM5, MIC2774N-XXBM5 Datasheet

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 power­on 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 VDD against a fixed threshold. Ten fac­tory-programmed thresholds are available. The second, user­adjustable 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 volt­ages 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 under­voltage 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 active­low reset outputs

• Inputs may be pulled above VDD (7V abs. max.)

• Open-drain output can be pulled above VDD (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 Marking Reset Output Temperature Range Package

MIC2774N-XXBM5 UGXX Open-Drain, Active-Low (/RST) –40°C to +85°C SOT-23-5

MIC2774H-XXBM5 UHXX Active-High, Complementary (RST) –40°C to +85°C SOT-23-5

MIC2774L-XXBM5 UIXX Active-Low, Complementary (/RST) –40°C to +85°C SOT-23-5

Typical Application

V

1.0V

CORE

V

2.5V

I/O

Power_Good

Manual
Reset

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

R1

R2

MIC2774L-23

/RST

VDD
IN

/MR GND

September 29, 2000 1 MIC2774

MICROPROCESSOR

VCORE

VI/O

/RESET

GND

MIC2774 Micrel

Standard Voltage Options*

Voltage Typical Nominal Threshold

Code Application (VDD) Voltage (VTH)

46 5.0V ±5% 4.68

44 5.0V ±10% 4.43

31 3.3V ±5% 3.09

29 3.3V ±10% 2.93

28 3.0V ±5% 2.81

26 2.85V ±5% 2.67

25 2.70V ±5% 2.53

23 2.5V ±5% 2.34

22 2.4V ±5% 2.25

17 1.8V ±5% 1.69

*There are ten standard versions available with an order increment of 3000 pieces. Samples of standard versions are
normally available from stock. Contact factory for information on non-standard versions. Available in tape-and-reel only.

Pin Configuration

GND

2

RST

13

VDDIN

/MR

45

SOT-23-5 (M5)

“H” Version

/MR

45

SOT-23-5 (M5)

“L” and “N” Version

GND

2

/RST

13

VDDIN

Pin Description

Pin Number Pin Number Pin Name Pin Function

MIC2774H MIC2774L

MIC2774N

1 RST Digital (Output): Asserted high whenever V

old voltage. It will remain asserted for no less than 140ms after V
return above the threshold limits.

1 /RST Digital (Output): Asserted low whenever V

voltage. It will remain asserted for no less than 140ms after V
return above the threshold limits. (open-drain for “N” version)

2 2 GND Ground

3 3 /MR Digital (Input): Driving this pin low initiates immediate and unconditional

reset. Assuming VIN and VDD 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 VDD and may be left open if unused.

4 4 IN Analog (Input): The voltage on this pin is compared to the internal 300mV

reference. An under-voltage condition will trigger a reset sequence.

5 5 VDD 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.

or VDD falls below the thresh-

IN

or VDD falls below the threshold

IN

and V

IN

and V

IN

DD

DD

MIC2774 2 September 29, 2000

MIC2774 Micrel

Absolute Maximum Ratings (Note 1)

Supply Voltage (V
Input Voltages (V
Output Voltages (V

RST, (/RST) Current .................................................. 20mA

Storage Temperature (T

ESD Rating, Note 3 ................................................... 1.5kV

) ..................................... –0.3V to +7V

DD

, V

IN

) .............................. –0.3V to +7V

/MR

, V

/RST

) ....................... –0.3V to +7V

RST

) ....................... –65°C to +150°C

S

Operating Ratings (Note 2)

Supply Voltage (V
Input Voltages (V
Output Voltages

V

(N version), .................................... –0.3V to +6.0V

/RST

V

, V

/RST

RST

Ambient Temperature Range (TA) ............. –40°C to +85°C

Package Thermal Resistance (θ

) .................................. +1.5V to +5.5V

DD

, V

IN

) ........................... –0.3V to +6.0V

/MR

(H and L versions) ......... –0.3V to VDD+0.3V

) ...................... 256°C/W

JA

Electrical Characteristics

Note 5; TA = +25°C, bold values indicate –40°C ≤ TA ≤ +85°C; unless noted

Symbol Parameter Condition Min Typ Max Units

I

DD

Supply Current VDD = V

VDD VOLTAGE THRESHOLD

Under-Voltage Threshold On V
(See Standard Voltage Options Table)

V

HYST

Hysteresis Voltage 1%

IN, UNDER-VOLTAGE DETECTOR INPUT

V

V

I

IN

REF

HYST

Under-Voltage Threshold Note 5 295 300 305 mV

Hysteresis Voltage 3mV

Input Current 5pA

RST, /RST OUTPUTS

t

PROP

Propagation Delay V

DD

Note 5; /MR, RST, /RST open

T

MIN

IN

V

IN

= VTH +1.6%, 3.5 µA

IN

≤ TA ≤ T

= (V

= (V

MAX

REF(MAX)

REF(MIN)

VTH–1.5%

+ 100mV) to 20 µs

– 100mV), /MR = open;

V

THVTH

+1.5%

V

10 nA

t

RST

V

V

OL

OH

Reset Pulse Width T

RST or /RST Output Voltage Low I

RST or /RST Output Voltage High I

≤ TA ≤ T

MIN

= 1.6mA; 0.3 V

SINK

VDD ≥ 1.6V

= 100µA; 0.3 V

I

SINK

VDD ≥ 1.2V; Note 4

SOURCE

MAX

= 500µA; 0.8V

140 280 ms

DD

VDD ≥ 1.5V

(H and L Version Only) I

SOURCE

= 10µA; 0.8V

DD

VDD ≥ 1.2V; Note 4

/MR INPUTS

V

IH

V

IL

t

PROP

t

MIN

I

PU

I

IN

Note 1. Exceeding the absolute maximum rating may damage the device.

Note 2. The device is not guaranteed to function outside its operating rating.

Note 3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.

Note 4. VDD operating range is 1.5V to 5.5V. Output is guaranteed to be asserted down to VDD = 1.2V.

Note 5. VDD equals nominal “Typical Application (VDD)” as shown in “Standard Voltage Options Table.”

Input High Voltage Note 5 0.7V

DD

Input Low Voltage Note 5 0.3V

Propagation Delay V

Minimum Input Pulse Width Reset Occurs, V

< (VIL –100mV); Note 5 5 µs

/MR

< V

/MR

IL

Internal Pull-up Current 100 nA

Input Current, /MR V

/MR

< V

IL

V

V

V

V

DD

33 ns

100 nA

September 29, 2000 3 MIC2774