Maxim MAX6315US50D4-T, MAX6315US50D2-T, MAX6315US50D1-T, MAX6315US49D4-T, MAX6315US49D3-T Datasheet

________________General Description

The MAX6315 low-power CMOS microprocessor (µP)
supervisory circuit is designed to monitor power sup­plies in µP and digital systems. It provides excellent cir­cuit reliability and low cost by eliminating external
components and adjustments. The MAX6315 also pro­vides a debounced manual reset input.

This device performs a single function: it asserts a reset
signal whenever the VCCsupply voltage falls below a
preset threshold or whenever manual reset is asserted.
Reset remains asserted for an internally programmed
interval (reset timeout period) after V

CC

has risen above
the reset threshold or manual reset is deasserted. The
MAX6315’s open-drain RESET output can be pulled up
to a voltage higher than VCC.

The MAX6315 comes with factory-trimmed reset thresh­old voltages in 100mV increments from 2.5V to 5V.
Preset timeout periods of 1ms, 20ms, 140ms, and
1120ms (minimum) are also available. The device
comes in a SOT143 package.

For microcontrollers (µCs) and µPs with bidirectional
reset pins, see the MAX6314 data sheet.

________________________Applications

Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment

____________________________Features

♦ Small SOT143 Package
♦ Open-Drain RESET Output Can Exceed V

CC

♦ Precision, Factory-Set VCCReset Thresholds:

100mV Increments from 2.5V to 5V

♦ ±1.8% Reset Threshold Accuracy at TA= +25°C
♦ ±2.5% Reset Threshold Accuracy Over Temp.
♦ Four Reset Timeout Periods Available:

1ms, 20ms, 140ms, or 1120ms (minimum)

♦ Immune to Short VCCTransients
♦ 5µA Supply Current
♦ Pin-Compatible with MAX811

MAX6315

Open-Drain SOT µP Reset Circuit

________________________________________________________________

Maxim Integrated Products

1

1

2

4

3

V

CC

MRRESET

GND

MAX6315

SOT143

TOP VIEW

__________________Pin Configuration

MAX6315

V

CC

V

CC

GND

RESET

µP

RESET

MR

LASER­TRIMMED
RESISTORS

RESET

CIRCUITRY

__________Typical Operating Circuit

19-2000; Rev 1; 1/99

Ordering and Marking Information appear at end of
data sheet.

For free samples & the latest literature: http://www.maxim-ic.com, or phone [phone].
For small orders, phone [phone].

MAX6315

Open-Drain SOT µP Reset Circuit

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= +2.5V to +5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

Note 1: The MAX6315 monitors VCCthrough an internal factory-trimmed voltage divider that programs the nominal reset threshold.

Factory-trimmed reset thresholds are available in 100mV increments from 2.5V to 5V (see

Ordering and Marking

Information

).

V

CC

........................................................................-0.3V to +6.0V

RESET....................................................................-0.3V to +6.0V

All Other Pins..............................................-0.3V to (V

CC

+ 0.3V)

Input Current (V

CC

).............................................................20mA

Output Current (RESET)......................................................20mA

Rate of Rise (V

CC

)...........................................................100V/µs

Continuous Power Dissipation (T

A

= +70°C)

SOT143 (derate 4mW/°C above +70°C)........................320mW

Operating Temperature Range ...........................-40°C to +85°C

Storage Temperature Range.............................-65°C to +160°C

Lead Temperature (soldering, 10sec).............................+300°C

MAX6315US_ _D3-T

MAX6315US_ _D2-T

MAX6315US_ _D4-T

TA= +25°C

VCC> 1.2V, I

SINK

= 0.5mA

VCC= 5.5V, no load

410

TA= -40°C to +85°C

VTH- 2.5% VTH+ 2.5%

1120 1570 2240

140 200 280

20 28 40

VCC> VTH, RESET deasserted

VTH> 4.0V

VCC= falling at 1mV/µs
MAX6315US_ _D1-T

VCC> 4.25V, I

SINK

= 3.2mA

CONDITIONS

VCC> 2.5V, I

SINK

= 1.2mA

VCC> 1.0V, I

SINK

= 80µA

0.3 x V

CC

2.4

0.7 x V

CC

0.3

0.3

V

µA1

RESET Output Leakage Current

V

0.4

V

OL

RESET Output Voltage

kΩ32 63 100

MR Pull-Up Resistance

VTH- 1.8% V

TH

VTH+ 1.8%

V

TH

Reset Threshold (Note 1)

µA

512

I

CC

V1.0 5.5V

CC

Operating Voltage Range
VCCSupply Current

ns500

MR to Reset Delay

ns100

MR Glitch Rejection

µs1

MR Minimum Input Pulse

V

0.8

V

IL

MR Input Threshold

ppm/°C60∆VTH/°CReset Threshold Tempco

µs35VCCto Reset Delay

ms

1 1.4 2

t

RP

Reset Timeout Period

UNITSMIN TYP MAXSYMBOLPARAMETER

V

IL

V

IH

V

IH

VCC= 3.6V, no load

TA= -40°C to +85°C

VTH< 4.0V

MANUAL RESET INPUT

MAX6315

Open-Drain SOT µP Reset Circuit

_______________________________________________________________________________________

3

6

0

-50 -30 30 90

SUPPLY CURRENT vs. TEMPERATURE

2

1

5

MAX6315-01

TEMPERATURE (°C)

SUPPLY CURRENT (µA)

-10 10 50

3

4

70

VCC = 5V

VCC = 3V

VCC = 1V

6

0

0

1

35

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

2

1

5

MAX6315-02

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

2

3

4

4

TA = -40°C

TA = +25°C

TA = +85°C

50

0

-50 -30 10 90

POWER-DOWN RESET DELAY

vs. TEMPERATURE

10

40

MAX6315-03

TEMPERATURE (°C)

POWER-DOWN RESET DELAY (µs)

-10

20

30

30 50 70

VCC FALLING AT 1mV/µs

VTH = 4.63V

VTH = 3.00V

1.04

0.96

-50 -30 10 90

NORMALIZED RESET TIMEOUT PERIOD

vs. TEMPERATURE (V

CC

RISING)

0.97

0.98

1.02

1.00

1.03

MAX6315-04

TEMPERATURE (°C)

NORMALIZED RESET TIMEOUT PERIOD

-10

0.99

1.01

30 50 70

1.006

0.994

-50 -30 10 90

NORMALIZED RESET THRESHOLD

vs. TEMPERATURE (V

CC

FALLING)

0.996

0.998

1.004

1.000

MAX6315-05

TEMPERATURE (°C)

NORMALIZED RESET THRESHOLD

-10

1.002

30 50 70

100

0

10 100 1000

MAXIMUM TRANSIENT DURATION

vs. RESET COMPARATOR OVERDRIVE

20

MAX6315-06

RESET COMP. OVERDRIVE, VTH - VCC (mV)

MAXIMUM TRANSIENT DURATION (µs)

40

60

80

TA = +25°C
RESET OCCURS
ABOVE CURVE

VTH = 4.63V

VT = 3.00V

__________________________________________Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)

______________________________________________________________Pin Description

NAME FUNCTION

1 GND Ground
2

RESET

Active-Low Open-Drain Output. Connect to an external pull-up resistor. Can be pulled up to a voltage
higher than VCC, but less than 6V.

PIN

3

MR

Manual Reset Input. A logic low on MR asserts reset. Reset remains asserted as long as MR is low, and
for the reset timeout period (t

RP

) after the reset conditions are terminated. Connect to VCCif not used.

4 V

CC

Supply Voltage and Reset Threshold Monitor Input