MAX6856UK16D3S-T - Maxim Integrated Products, Inc.

General Description

The MAX6854/MAX6855/MAX6856/MAX6858/MAX6860–

MAX6869 ultra-low-current (170nA, typ) microprocessor

(µP) supervisory circuits combine voltage monitoring,

watchdog timer, and manual reset input functions in a 5-

pin SOT23 package. These devices assert a reset signal

whenever the monitored voltage drops below the factory-

trimmed reset threshold voltage, manual reset is assert-

ed, or the watchdog timer expires. The reset output

remains asserted for a minimum timeout period after VCC

rises above the reset threshold and manual reset is

deasserted. Factory-trimmed reset threshold voltages

are offered from +1.575V to +4.625V in approximately

100mV increments (see Threshold Suffix Guide). Each

device is offered with six minimum reset timeout options,

ranging from 10ms to 1200ms.

The MAX6854/MAX6855/MAX6856/MAX6858/MAX6860–

MAX6869 are offered in a variety of configurations (see

the Selector Guide). The MAX6854/MAX6855/MAX6856/

MAX6861–MAX6869 provide a manual reset input, MR.

The MAX6864–MAX6869 offer a watchdog timer that

monitors activity at the WDI input to prevent code execu-

tion errors. The MAX6864–MAX6869 offer watchdog

timeout options of 3.3s or 209s (typ). The MAX6861/

MAX6862/MAX6863 feature a pin-selectable reset delay

period of 10ms or 150ms (min). Push-pull active-low,

push-pull active-high, and open-drain active-low reset

outputs are available. Applications

Portable/Battery-Powered Equipment

PDAs/Cell Phones

MP3 Players/Pagers

Glucose Monitors/Patient Monitors

Features

♦Ultra-Low 170nA (typ) Supply Current

♦Reset Thresholds from +1.575V to +4.625V in

Approximately 100mV Increments

♦Six Minimum Reset Timeout Period Options from

10ms to 1200ms

♦Manual Reset Option

♦Watchdog Timer Option

♦Pin-Selectable 10ms/150ms (min) Reset Timeout

Period (MAX6861/MAX6862/MAX6863)

♦Immune to Short VCC Transients

♦Guaranteed Reset Valid to VCC = +1.1V

♦Three Reset Output Options:

Push-Pull RESET

Open-Drain RESET

♦No External Components

♦Small 5-Pin SOT23 Package

♦Pin Compatible to the TPS3836/TPS3837/TPS3838

(MAX6861/MAX6862/MAX6863)

MAX6854/MAX6855/MAX6856/MAX6858/MAX6860–MAX6869

Nanopower µP Supervisory Circuits with

Manual Reset and Watchdog Timer

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

PART†TEMP RANGE PIN-PACKAGE

MAX6854UK_ _D_-T -40°C to +85°C 5 SOT23-5

MAX6855UK_ _D_-T -40°C to +85°C 5 SOT23-5

19-3139; Rev 2; 9/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Ordering Information continued at end of data sheet.

†Insert reset threshold suffix (see Table 2, Threshold Suffix

Guide) after UK. Insert the number corresponding to the

desired reset timeout period (see Table 4, Reset Timeout

Period) after D.

Note: Sample stock is generally held on standard versions

only (see Table 5, Standard Versions Table). Standard versions

have an order increment of 2500 pieces. Nonstandard versions

have an order increment of 10,000 pieces. Contact factory for

availability of nonstandard versions.

Pin Configurations appear at end of data sheet.

Selector Guide appears at end of data sheet.

Typical Operating Circuit

MAX6864

MAX6867

µP

VCC

GND GND

MANUAL

RESET

I/O

VCC

0.1µF

RESET

MR WDI

MAX6854/MAX6855/MAX6856/MAX6858/MAX6860–MAX6869

Nanopower µP Supervisory Circuits with

Manual Reset and Watchdog Timer

2_______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC = 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise specified. Typical values are at VCC = 2.5V, TA= +25°C.) (Note 1)

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.

VCC, Open-Drain RESET to GND ..........................-0.3V to +6.0V

MR, Push-Pull RESET, RESET,

WDI, CT, I.C............................................-0.3V to (VCC + 0.3V)

Input Current, Output Current (all pins)............................±20mA

Continuous Power Dissipation (TA= +70°C)

5-Pin SOT23 (derate 7.1mW/°C above +70°C)............571mW

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

Junction Temperature .....................................................+150°C

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

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

PARAMETER

SYMBOL

CONDITIONS MIN

TYP

MAX

UNITS

TA ≥ 0°C 1.1 5.5

Supply Voltage VCC TA = -40°C to +85°C 1.2 5.5 V

VCC = 5.0V 210 400

VCC = 3.3V 190 380

VCC > VTH, no load,

reset output

deasserted (Note 2)

VCC = 1.8V 170 370

Supply Current ICC

VCC < VTH, no load, reset output asserted

715µA

VCC Reset Threshold VTH VCC falling (see Table 2) VTH -

2.5%

VTH VTH +

2.5%

Reset Threshold Hysteresis VHYST Reset asserted to reset deasserted 0.5

%VTH

D1 10 15 25

D2 40 60 80

D3 150 225 300

1200 1800 2400

D5 300 450 600

Reset Timeout Period tRP VCC = VTH + 150mV

(Figures 2 and 3)

D6 600 900

1200

VCC to Reset Delay tRD VCC falling from (VTH + 100mV) to

(VTH - 100mV) at 10mV/µs 40 µs

VCC ≥ 1.1V, ISINK = 50µA,

RESET asserted, TA ≥ 0°C 0.3

VCC ≥ 1.2V, ISINK = 100µA,

RESET asserted 0.3

VOL

VCC ≥ 2.12V, ISINK = 1.2mA,

RESET asserted 0.3

VCC ≥ 1.71V, ISOURCE = 200µA,

RESET deasserted, push-pull RESET only 0.8 x VCC

RESET Output Voltage

VOH VCC ≥ 2.38V, ISOURCE = 500µA,

RESET deasserted, push-pull RESET only 0.8 x VCC

Open-Drain RESET Leakage

Current ILKG RESET deasserted 25 nA

MAX6854/MAX6855/MAX6856/MAX6858/MAX6860–MAX6869

Nanopower µP Supervisory Circuits with

Manual Reset and Watchdog Timer

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC = 1.2V to 5.5V, TA= -40°C to +85°C, unless otherwise specified. Typical values are at VCC = 2.5V, TA= +25°C.) (Note 1)

PARAMETER

SYMBOL

CONDITIONS MIN

TYP MAX

UNITS

VCC ≥ 1.1V, ISOURCE = 10µA,

RESET asserted, TA ≥ 0°C 0.8 x VCC

VCC ≥ 1.2V, ISOURCE = 10µA,

RESET asserted 0.8 x VCC

VCC ≥ 1.53V, ISOURCE = 200µA,

RESET asserted 0.8 x VCC

VOH

VCC ≥ 2.12V, ISOURCE = 500µA,

RESET asserted 0.8 x VCC

VCC ≥ 1.71V, ISINK = 500µA,

RESET deasserted 0.3

RESET Output Voltage

VOL VCC ≥ 2.38V, ISINK = 1.2mA,

RESET deasserted 0.3

CT Input Current CT = GND or VCC 20 nA

VIH 0.8 x VCC

CT Input Voltage VIL

0.2 x VCC

MANUAL RESET INPUT

VIH 0.7 x VCC

MR Input Voltage VIL

0.3 x VCC

MR Minimum Pulse Width tMPW 1µs

MR Glitch Rejection 200 ns

MR to Reset Delay tMRD 250 ns

MR Pullup Resistance 51020kΩ

WATCHDOG TIMER (MAX6864–MAX6869)

VIH 0.7 x VCC

WDI Input Voltage VIL

0.3 x VCC

WDI Input Current WDI = GND or VCC 20 nA

WDI Pulse Width tWDI (Note 3) 150 ns

S 1.5 3.3

7.75

Watchdog Timeout Period tWD L95209 487 s

Note 1: Devices are tested at TA= +25°C. Specifications for TA= -40°C to +85°C are guaranteed by design.

Note 2: For the MAX6864–MAX6869, the watchdog period is 1s with tRISE and tFALL < 50ns.

Note 3: Guaranteed by design.