Datasheet SG3546DM, SG3546LP Datasheet (Microsemi Corporation)

LIN DOC #:

3546

SG3546

3.3V UNDERVOLTAGE SENSING CIRCUIT

THE INFINITE POWER OF INNOVATION

DESCRIPTION

The SG3546 is an undervoltage sensing
circuit specifically designed for use as
a reset controller in 3.3V
microprocessor-based applications. Its
micropower operation makes this
device ideal for portable applications
where extended battery life is required.
The device offers a 1.2V temperature
compensated bandgap reference, a

precision comparator with hysteresis
and a high-current open collector
output. This device operates from 1 to
10V input supply and drains <10µA in
the non-fault condition.

The SG3546 is available in an 8-pin
150mil SOIC package or a 3-pin TO-92
package and is rated for an ambient
temperature of 0°C to 70°C.

PRODUCT HIGHLIGHT

LOW-VOLTAGE MICROPROCESSOR RESET

2

1

POWER

SUPPLY

R
RESET

MICROPROCESSOR

C

DLY

P RODUCTION DAT A SHEET

KEY FEATURES

■ LOW STANDBY CURRENT

■ INTERNAL VOLTAGE THRESHOLD AT 2.95V

■ TEMPERATURE COMPENSATED BANDGAP

REFERENCE

■ PRECISION COMPARATOR WITH 40MV OF

HYSTERESIS

■ CLAMP DIODE FOR DISCHARGING DELAY

CAPACITOR

■ OUTPUT CURRENT SINK CAPABILITY

(typ 5mA)

■ 1-10V INPUT SUPPLY RANGE

■ AVAILABLE IN 150MIL, 8-PIN SOIC AND

3-PIN TO-92 PACKAGES

CIRCUIT

1.2 V

REF

3

PACKAGE ORDER INFORMATION

T

(°C)

A

Plastic SOIC

DM

8-pin

Plastic TO-92

LP

3-pin

0 to 70 SG3546DM SG3546LP

Note: All surface-mount packages are available in Tape & Reel.

Append the letter "T" to part number. (i.e. SG3546DMT)

Copyright © 1994
Rev. 1.3 1/96

FOR FURTHER INFORMATION CALL [phone]

11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841

1

SG3546

PRODUCT DATABOOK 1996/1997

3.3V U

NDERVOLTAGE SENSING CIRCUIT

RODUCTION DATA SHEET

P

ABSOLUTE MAXIMUM RATINGS (Note 1)

Input Supply Voltage (VIN)............................................................................... -1V to 12V

RESET Output Voltage (V

Clamp Diode Forward Current .............................................................................. 100mA

) .......................................................................... -1V to 12V

OUT

Operating Junction Temperature

Plastic (DM - Package) ......................................................................................... 150°C

Storage Temperature Range...................................................................... -65°C to 150°C

Lead Temperature (Soldering, 10 seconds) ............................................................ 300°C

Note 1. Values beyond which damage may occur. All voltages are specified with respect to

ground, and all currents are positive into the specified terminal.

THERMAL DATA

DM PACKAGE:

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

θθ

θ

θθ

JA

LP PACKAGE:

D

θθ

θ

θθ

x θ

JA

).

JA

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

Junction Temperature Calculation: TJ = TA + (P
The θ

numbers are guidelines for the thermal performance of the device/pc-board system.

JA

All of the above assume no ambient airflow.

165°C/W

156°C/W

PACKAGE PIN OUTS

RESET

INPUT

N.C.

GROUND

1 8
2 7
3 6
4 5

DM PACKAGE

(Top View)

LP PACKAGE

(Top View)

N.C.
N.C.
N.C.
N.C.

3. GROUND

2. INPUT

1. RESET

INPUT

2

BLOCK DIAGRAM

1.2 V

REF

4

GROUND

RESET

1

2

Copyright © 1994

Rev. 1.3 2/96

PRODUCT DATABOOK 1996/1997

SG3546

3.3V UNDERVOLTAGE SENSING CIRCUIT

P RODUCTION DAT A SHEET

RECOMMENDED OPERATING CONDITIONS (Note 2)

Parameter

Input Supply Voltage
RESET Output Voltage

Clamp Diode Forward Current

Operating Ambient Temperature Range:

SG3546 T

Note 2. Range over which the device is guaranteed functional.

Symbol

A

ELECTRICAL CHARACTERISTICS

(Unless otherwise specified, these specifications apply over the operating ambient temperatures of 0°C ≤ TA ≤ 70°C for the SG3546. Low duty cycle
pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.)

Parameter

Symbol

Test Conditions Units

Total Device

Operating Input Voltage Range V
Quiescent Input Current I

IN

IN

VIN = 3.3V

= 10V

V

IN

Comparator Section

Threshold Voltage

High-State Output V
Low-State Output VILVIN Decreasing

Hysteresis V

IH

H

VIN Increasing

RESET Output Section

Output Sink Saturation V

Output Sink Current I

Output Off-State Leakage V

Clamp Diode Forward Voltage VFPin 1 to pin 2, (IF = 5.0mA)

OLVIN

SINKVIN

= 2.6V, I

= 1.0V, I

V

IN

, RESET = 2.6V

, RESET = 3.6V

IN

VIN , RESET = 10V

= 1mA

SINK

= 100µA

SINK

Recommended Operating Conditions

Min. Typ. Max.

110V

10 V

50 mA

070°C

Units

SG3546

Min. Typ. Max.

1.0 10 V

10 20 µA
19 50 µA

2.75 2.81 3.0 V

2.75 2.86 3.0 V
40 mV

0.05 0.40 V

0.06 0.30 V
20 mA

0.5 µA

2.0 µA

0.5 1.2 V

Copyright © 1994
Rev. 1.3 2/96

3

SG3546

PRODUCT DATABOOK 1996/1997

3.3V U

GRAPH / CURVE INDEX

NDERVOLTAGE SENSING CIRCUIT

RODUCTION DATA SHEET

P

Characteristic Curves

FIGURE #

1. COMPARATOR THRESHOLD VOLTAGE vs. TEMPERATURE

2. RESET OUTPUT VOLTAGE vs. INPUT VOLTAGE

3. RESET OUTPUT SATURATION vs. SINK CURRENT

4. INPUT CURRENT vs. INPUT VOLTAGE

5. RESET DELAY TIME (LOW to HIGH)

6. RESET DELAY TIME (HIGH to LOW)

FIGURE INDEX

Application Circuits

FIGURE #

7. SWITCHING THE LOAD OFF WHEN BATTERY REACHES BELOW V

8. LOW VOLTAGE MICROPROCESSOR RESET

9. VOLTAGE MONITOR

TH

4

Copyright © 1994

Rev. 1.3 2/96

PRODUCT DATABOOK 1996/1997

0

0

Input Voltage - (V)

Input Current - (µA)

10

0.5

70

20

30

40

50

60

1 22.533.5

R

L

= ¥

TA = 25°C

1.5 4

3.3V UNDERVOLTAGE SENSING CIRCUIT

P RODUCTION DAT A SHEET

CHARACTERISTIC CURVES

SG3546

FIGURE 1. — COMPARATOR THRESHOLD VOLTAGE

vs. TEMPERATURE

RL = 43K to V

3.050

3.000

2.950

2.900

2.850

Threshold Voltage - (V)

2.800

2.750

-50

-25 0 25 50 75 100 125

Junction Temperature - (°C)

FIGURE 3. — RESET OUTPUT SATURATION

vs. SINK CURRENT

FIGURE 2. — RESET OUTPUT VOLTAGE

vs. INPUT VOLTAGE

IN

4

3

2

RL = 82K to V
TA = 25°C

IN

Output Voltage - (V)

1

0

0

1

2345

Input Voltage - (V)

FIGURE 4. — INPUT CURRENT vs. INPUT VOLTAGE

Copyright © 1994
Rev. 1.3 2/96

) Output Saturation - (mV)

OL

(V

300

200

TA = 25°C

VIN = 3V

100

0

0

3 6 9 12 14

(I

) Sink Current - (mA)

SINK

5

SG3546

0%

0.5µs/DIV.

REF

43K

RESET

3.3V

2.7V

V

IN

3.3V

2.7V

VIN = 4.0V to 5.0V
RL = 43K
TA = 25°C

100%

PRODUCT DATABOOK 1996/1997

3.3V U

NDERVOLTAGE SENSING CIRCUIT

RODUCTION DATA SHEET

P

CHARACTERISTIC CURVES

FIGURE 5. — RESET DELAY TIME (LOW TO HIGH)

V

3.3V

2.7V

IN

REF

43K

RESET

100%

3.3V

2.7V

VIN = 3.3V to 2.6V
RL = 43K

0%

TA = 25°C

FIGURE 6. — RESET DELAY TIME (HIGH TO LOW)

2µs/DIV.

6

Copyright © 1994

Rev. 1.3 2/96

PRODUCT DATABOOK 1996/1997

3.3V UNDERVOLTAGE SENSING CIRCUIT

P RODUCTION DAT A SHEET

TYPICAL APPLICATION CIRCUITS

SG3546

2

1

RESET

1.2 V

REF

4

FIGURE 7. — SWITCHING THE LOAD OFF WHEN

BATTERY VOLTAGE REACHES BELOW V

TH

LOAD

POWER

SUPPLY

2

1.2 V

REF

3

R

1

RESET

MICROPROCESSOR

C

CIRCUIT

DLY

A time-delayed reset can be accomplished with the addition of C
For systems with extremely fast power supply rise times (< 500ns),
it is recommended that the RC

5.0µs. V

is the microprocessor reset input threshold.

TH(MPU)

time constant be greater than

DLY

1

t

DLY

= R C

DLY

In

FIGURE 8. — LOW VOLTAGE MICROPROCESSOR RESET

1 -

V

TH(MPU)

V

IN

DLY

.

POWER
SUPPLY

Copyright © 1994
Rev. 1.3 2/96

2

1.2 V

REF

3

FIGURE 9. — VOLTAGE MONITOR

1.0k

1

RESET

7