Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - system monitor Serialiser TQFN 32 EP

General Description

The MAX6892/MAX6893/MAX6894 pin-selectable, mul-

tivoltage supply sequencers/supervisors monitor sever-

al voltage-detector inputs and one watchdog input,

asserting the respective voltage detector or watchdog

output when the inputs drop below the configured volt-

age thresholds or the watchdog timer expires. The

MAX6892 features eight voltage detector inputs and 10

outputs. The MAX6893 features six voltage-detector

inputs and eight outputs, while the MAX6894 features

four voltage detector inputs and six outputs. A RESET

output ensures all monitored inputs are above the set

thresholds. The voltage detector outputs are configured

as open drain. Manual reset and margin disable inputs

offer additional flexibility.

The thresholds of the MAX6892/MAX6893/MAX6894 are

selected through five logic inputs (TH0–TH4). The logic on

these five inputs selects the supply voltage tolerance (5%

or 10%) and one of 32 factory-set thresholds settings.

Watchdog and reset timeout periods can use factory

default settings or are independently adjustable by con-

necting external capacitors.

When any of the monitored voltages falls below its

threshold, the respective output asserts and remains

asserted for 6.25ms (typ) after the monitored voltage

exceeds the threshold. The outputs can be connected

to the shutdown or enable inputs of DC-DC regulators

to provide turn-on power sequencing to ensure proper

system initialization.

The MAX6892 is available in a 5mm x 5mm x 0.8mm,

32-pin, Thin QFN package, while the MAX6893/

MAX6894 are available in a 5mm x 5mm x 0.8mm, 28-

pin, Thin QFN package. The MAX6892/MAX6893/

MAX6894 are specified to operate over the extended

temperature range (-40°C to +85°C).

Applications

Telecommunication/Central Office Systems

Networking Systems

Servers/Workstations

Base Stations

Storage Equipment

Multimicroprocessor/Voltage Systems

Features

o Pin-Selectable or User-Adjustable Voltage

Detector Thresholds

o Dedicated RESET and WDO Outputs

o Capacitor-Adjustable Reset and Watchdog

Timeout Periods

o Factory-Default Reset and Watchdog Timeout

Periods

o Up to Eight Independent, Open-Drain Power-Good

Outputs

o Enable Margining Disable and Manual Reset

Controls

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

o Small 5mm x 5mm Thin QFN Package

o Few External Components

o ±1% Threshold Accuracy

MAX6892/MAX6893/MAX6894

Pin-Selectable, Octal/Hex/Quad, Power-Supply

Sequencers/Supervisors

________________________________________________________________

Maxim Integrated Products

PART TEMP RANGE PIN-PACKAGE

MAX6892ETJ -40°C to +85°C 32 Thin QFN-EP*

MAX6893ETI -40°C to +85°C 28 Thin QFN-EP*

MAX6894ETI -40°C to +85°C 28 Thin QFN-EP*

Ordering Information

19-3596; Rev 2; 9/10

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

Typical Operating Circuit appears at end of data sheet.

Pin Configurations

32 31 30 29 28 27 26

9 101112131415

MAX6892

THIN QFN

TOP VIEW

PG3

PG2

PG4

GND

PG5

PG6

PG7

*EP

*EXPOSED PAD INTERNALLY CONNECTED TO GND.

PG8

PG1

WDI

IN1

IN2

IN3

IN4

IN5

IN6

IN7

IN8

DBP

ENABLE

SRT

SWT

TH4

TH2

TH1

TH3

TH0

MARGIN

WDO

RESET

Pin Configurations continued at end of data sheet.

Note: Devices are also available in a lead(Pb)-free/RoHS-compli-

ant package. Specify lead-free by adding a plus (+) to the part

number when ordering.

EP = Exposed pad.

Summary of content (19 pages)

PAGE 1
9-3596; Rev 2; 9/10 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors Features The MAX6892/MAX6893/MAX6894 pin-selectable, multivoltage supply sequencers/supervisors monitor several voltage-detector inputs and one watchdog input, asserting the respective voltage detector or watchdog output when the inputs drop below the configured voltage thresholds or the watchdog timer expires. The MAX6892 features eight voltage detector inputs and 10 outputs.
PAGE 2
MAX6892/MAX6893/MAX6894 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) PG_, RESET, WDO .................................................-0.3V to +14V IN1–IN8, TH0–TH4, ENABLE, WDI, MR, MARGIN, SRT, SWT, VCC .....................................................-0.3V to +6V DBP ..........................................................................-0.3V to +3V Input/Output Current (all pins)....................................
PAGE 3
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors (VIN1 = VIN6–VIN8 = VGND, VIN2–VIN5 = 2.7V to 5.5V, WDI = ENABLE = GND, TH0–TH4 = MARGIN = MR = DBP, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.
PAGE 4
MAX6892/MAX6893/MAX6894 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors ELECTRICAL CHARACTERISTICS (continued) (VIN1 = VIN6–VIN8 = VGND, VIN2–VIN5 = 2.7V to 5.5V, WDI = ENABLE = GND, TH0–TH4 = MARGIN = MR = DBP, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS TH0–TH4 Input Current WDI Pulldown Current Watchdog Adjustable Timeout Period SWT Adjustable Timeout Current IWDI VWDI = 0.
PAGE 5
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors SUPPLY CURRENT vs. SUPPLY VOLTAGE (IN2–IN5) 0.8 TA = +25°C TA = -40°C 0.6 3.0 3.5 4.0 4.5 5.0 TA = -40°C TA = +25°C 1.2 1.1 1.0 0.9 0.8 0.7 2.5 3.0 3.5 4.0 4.5 5.0 -40 5.5 -15 10 35 60 SUPPLY VOLTAGE (V) TEMPERATURE (°C) IN_ TO PG_ PROPAGATION DELAY vs. TEMPERATURE NORMALIZED DEFAULT RESET TIMEOUT PERIOD vs. TEMPERATURE NORMALIZED ADJUSTABLE RESET TIMEOUT PERIOD vs. TEMPERATURE 22 20 18 16 14 12 10 1.010 1.
PAGE 6
Typical Operating Characteristics (continued) (VIN1 = VIN6–VIN8 = VGND, VIN2–VIN5 = 2.7V to 5.5V, VWDI = VGND, VTH0–VTH4 = V MARGIN = V MR = VDBP. Typical values are at TA = +25°C.) MAXIMUM IN_ TRANSIENT vs. IN_ THRESHOLD OVERDRIVE OUTPUT VOLTAGE LOW vs.
PAGE 7
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors PIN NAME MAX6892 MAX6893 MAX6894 1 1 1 PG2 2 2 2 PG3 3 3 3 PG4 4 4 4 GND 5 5 — PG5 6 6 — PG6 7 — — PG7 8 — — PG8 9 7 7 RESET 10 8 8 WDO 11 9 9 MARGIN 12 10 10 MR 13 11 11 TH0 FUNCTION Open-Drain, Power-Good Output 2. PG2 asserts low when the voltage input at IN2 is below the pin-selectable/adjustable input threshold or ENABLE is pulled high.
PAGE 8
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors MAX6892/MAX6893/MAX6894 Pin Description (continued) PIN 8 NAME MAX6892 MAX6893 MAX6894 14 12 12 TH1 15 13 13 TH2 16 14 14 TH3 17 15 15 TH4 18 16 16 SWT 19 17 17 SRT 20 18 18 ENABLE 21 19 19 VCC 22 20 20 DBP 23 — — IN8 24 — — IN7 FUNCTION Threshold Selection Input 1. Logic input to select desired thresholds. Connect TH1 to GND or DBP. See Table 2 for available thresholds.
PAGE 9
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors PIN NAME MAX6892 MAX6893 MAX6894 25 21 — IN6 26 22 — IN5 27 23 23 IN4 28 24 24 IN3 29 25 25 IN2 30 26 26 IN1 31 27 27 WDI 32 28 28 PG1 — — 5, 6, 21, 22 N.C. — — — EP FUNCTION Input Voltage 6. Select undervoltage threshold using TH0–TH4. See Table 2. For improved noise immunity, bypass IN6 to GND with a 0.1µF capacitor as close to the device as possible. Input Voltage 5.
PAGE 10
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors ENABLE WOI MARGIN MR MAX6892/MAX6893/MAX6894 Functional Diagram IN_ DETECTOR IN2 PG_ OUTPUT OPEN-DRAIN ACTIVE-LOW PG1 10μA POWER-UP PULLDOWN VREF SWT IN2 DETECTOR IN3 IN3 DETECTOR IN4 IN4 DETECTOR IN5* IN5 DETECTOR IN6* IN6 DETECTOR IN7** IN7 DETECTOR IN8** IN8 DETECTOR (VIRTUAL DIODES) 2.
PAGE 11
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors The MAX6892/MAX6893/MAX6894 pin-selectable, multivoltage supply sequencers/supervisors monitor several voltage detector inputs and one watchdog input, asserting the outputs when the respective input thresholds have been reached or a timeout occurs. All versions have an enable manual reset and margin input disable. The MAX6892/MAX6893/MAX6894 voltage thresholds are selected by logic inputs and/or an external voltage-divider.
PAGE 12
MAX6892/MAX6893/MAX6894 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors Threshold Logic Inputs (TH0–TH4) The TH0–TH4 logic inputs select the undervoltage thresholds and tolerance of the IN1–IN8 inputs (MAX6892), IN1–IN6 inputs (MAX6893), and IN1–IN4 inputs (MAX6894). TH0–TH4 define 32 unique options for the supervisor functionality. Connect the respective TH_ to GND for a logic 0 or to DBP for a logic 1. Tables 1 and 2 show the 32 unique threshold options available.
PAGE 13
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors MAX6892/MAX6893/MAX6894 Table 2. Threshold Options THRESHOLD VOLTAGES (V) SELECTION TH4–TH0* IN1 IN2 IN3 IN4 IN5 IN6 IN7 IN8 1 11111 0.60 4.62 3.06 2.31 1.67 0.60 0.60 0.60 2 11110 0.60 4.62 2.78 2.31 1.67 0.60 0.60 0.60 3 11101 0.60 4.62 3.06 2.31 0.60 0.60 0.60 0.60 4 11100 0.60 4.62 2.78 2.31 0.60 0.60 0.60 0.60 5 11011 0.60 4.62 3.06 1.67 0.60 0.60 0.60 0.60 6 11010 0.
PAGE 14
MAX6892/MAX6893/MAX6894 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors Watchdog Timer The MAX6892/MAX6893/MAX6894s’ watchdog circuit monitors the microprocessor’s (µP’s) activity. If the µP does not toggle the watchdog input (WDI) within the watchdog timeout period, the watchdog output (WDO) asserts. The internal watchdog timer is cleared by RESET, or by a transition at WDI (which can detect pulses as short as 50ns). The watchdog timer remains cleared while reset is asserted.
PAGE 15
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors MR is designed to reject fast falling transients (typically 100ns pulses) and it must be held low for a minimum of 1µs to assert RESET. After MR transitions from low to high, RESET remains asserted for the duration of the reset timeout period. Margin Output Disable (MARGIN) MARGIN allows system-level testing while power supplies exceed the normal ranges.
PAGE 16
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors + N.C. 22 IN4 23 IN3 IN5 24 IN2 IN4 25 IN1 IN3 26 WDI IN2 27 PG1 IN1 28 TOP VIEW 28 27 26 25 24 23 22 PG2 1 21 IN6 PG2 1 21 N.C. PG3 2 20 DBP PG3 2 20 DBP PG4 3 19 VCC PG4 3 19 VCC GND 4 18 ENABLE GND 4 18 ENABLE PG5 5 17 SRT N.C. 5 17 SRT PG6 6 16 SWT N.C.
PAGE 17
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors 5V 5V DC-DC 1 3.3V DC-DC 2 VCC IN1 IN2 PG2 IN3 PG3 2.5V DC-DC 3 IN4 PG4 1.8V DC-DC 4 IN5 PG5 1.5V IN6 RESET WDI WDO DBP TH0 MAX6893 μP RESET LOGIC OUTPUT LOGIC INPUT MARGIN TH1 TH2 TH3 MR TH4 ENABLE SRT SWT CSRT tPG2 3.3V OUTPUT tPG3 ENABLE 2.5V DC-DC CONVERTER 2.5V OUTPUT 2.5V SUPPLY tPG4 PG4 1.8V SUPPLY 1.5V SUPPLY RESET ENABLE 1.8V DC-DC CONVERTER 1.8V OUTPUT tPG5 PG5 CSWT ENABLE 3.3V DC-DC CONVERTER 3.
PAGE 18
MAX6892/MAX6893/MAX6894 Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors Package Information Chip Information PROCESS: BiCMOS 18 For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO.
PAGE 19
Pin-Selectable, Octal/Hex/Quad, Power-Supply Sequencers/Supervisors REVISION NUMBER REVISION DATE 0 2/05 Initial release 9/10 Add lead-free package, add exposed pad info, update Absolute Maximum Ratings, style edits 1 DESCRIPTION PAGES CHANGED — 1–6, 8–11, 13, 15, 16, 18, 19 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.