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MAX16052中文资料

General Description

The MAX16052/MAX16053 are a family of small, low-power, high-voltage monitoring circuits with sequenc-ing capability. These miniature devices offer very wide flexibility with an adjustable voltage threshold and an external capacitor-adjustable time delay. These devices are ideal for use in power-supply sequencing,reset sequencing, and power switching applications.Multiple devices can be cascaded for complex sequencing applications.

A high-impedance input (IN) with a 0.5V threshold allows an external resistive divider to set the monitored threshold. The output (OUT) asserts high when the input voltage rises above the 0.5V threshold and the enable input (EN) is asserted high. When the voltage at IN falls below 0.495V or when the enable input is deasserted (EN = low), the output deasserts (OUT =low). The MAX16052/MAX16053 provide a capacitor programmable delay time from when the voltage at IN rises above 0.5V to when the output is asserted.

The MAX16052 offers an active-high open-drain output while the MAX16053 offers an active-high push-pull out-put. Both devices operate from a 2.25V to 16V supply voltage and feature an active-high enable input. The MAX16052/MAX16053 are available in a tiny 6-pin SOT23 package and are fully specified over the auto-motive temperature range (-40°C to +125°C).

Applications

Features

o 1.8% Accurate Adjustable Threshold Over Temperature

o Open-Drain (28V Tolerant) Output Allows Interfacing to 12V Intermediate Bus Voltage o Operates from V CC of 2.25V to 16V o Low Supply Current (18μA typ)o Capacitor-Adjustable Delay o Active-High Logic-Enable Input

o Fully Specified from -40°C to +125°C o Small 6-Pin SOT23 Package

MAX16052/MAX16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

________________________________________________________________Maxim Integrated Products 1

Pin Configuration

Typical Operating Circuit

19-4144; Rev 1; 10/08

For pricing, delivery, and ordering information,please contact Maxim Direct at 1-888-629-4642,or visit Maxim’s website at https://www.wendangku.net/doc/0e15681368.html,.

Automotive Medical Equipment Intelligent Instruments Portable Equipment

Computers/Servers Critical μP Monitoring Set-Top Boxes Telecom

Ordering Information

automotive temperature range.

+Denotes a lead-free/RoHS-compliant package.T = Tape and reel, offered in 2.5k increments.

M A X 16052/M A X 16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V CC = 2.25V to 16V, V EN = V CC , T A = T J = -40°C to +125°C, unless otherwise specified. Typical values are at V CC = 3.3V and T A =+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.

(All voltages referenced to GND.)

V CC .........................................................................-0.3V to +30V OUT (push-pull, MAX16053)......................-0.3V to (V CC + 0.3V)OUT (open-drain, MAX16052)................................-0.3V to +30V EN, IN.........................................................-0.3V to (V CC + 0.3V)CDELAY....................................................................-0.3V to +6V Input/Output Current (all pins)..........................................±20mA

Continuous Power Dissipation (T A = +70°C)

6-Pin SOT23 (derate 8.7mW/°C above +70°C)..........695.7mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature......................................................+150°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°C

MAX16052/MAX16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

_______________________________________________________________________________________

CC CC state cannot be determined.

Note 3:During the initial power-up, V CC must exceed 2.25V for at least 0.5ms before OUT can go high.

ELECTRICAL CHARACTERISTICS (continued)

(V CC = 2.25V to 16V, V EN = V CC , T A = T J = -40°C to +125°C, unless otherwise specified. Typical values are at V CC = 3.3V and T A =+25°C.) (Note 1)

M A X 16052/M A X 16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits 4_______________________________________________________________________________________

Figure 1. MAX16052/MAX16053 Timing Diagram (C CDELAY = 0)

MAX16052/MAX16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

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SUPPLY CURRENT vs. SUPPLY VOLTAGE

V CC (V)

I C C (μA )

1412

810

3691215182124273000

SUPPLY CURRENT vs. TEMPERATURE

TEMPERATURE (°C)

I C C (μA )

110956580-105203550-2536

912151821242730

-40125

IN THRESHOLD VOLTAGE vs. TEMPERATURE

M A X 16052/53 t o c 03

I N T H R E S H O L D V O L T A G E (m V )

498.5499.0499.5500.0500.5501.0501.5502.0498.0

TEMPERATURE (°C)

110956580-105203550-25-40125

OUT DELAY vs. C CDELAY

M A X 16052/53 t o c 04

C CDELAY (nF)

O U T D E L A Y (m s )900800600700200300400500100500100015002000250030003500400045005000

01000

OUTPUT LOW VOLTAGE vs. SINK CURRENT

I SINK (mA)O U T P U T L O W V O L T A G E (V )

18162

10128

141234567800

20OUTPUT HIGH VOLTAGE vs. SOURCE CURRENT

M A X 16052/53 t o c 06

I SOURCE (mA)

O U T P U T H I G H V O L T A G E (V )

12108642246810120

014

Typical Operating Characteristics

(V CC = 3.3V and T A = +25°C, unless otherwise noted.)

IN LEAKAGE CURRENT vs. TEMPERATURE

TEMPERATURE (°C)

I N L E A K A G E C U R R E N T (m A )

110956580-105203550-25123456789100

-40125

IN LEAKAGE CURRENT vs. IN VOLTAGE

IN VOLTAGE (V)

I N L E A K A G E C U R R E N T (n A )

-8-6

-4-20246810

-10

M A X 16052/M A X 16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits 6

_______________________________________________________________________________________

Typical Operating Characteristics

(T A = +25°C, unless otherwise noted.)

MAXIMUM TRANSIENT DURATION

vs. INPUT OVERDRIVE

INPUT OVERDRIVE (mV)

M A X I M U M T R A N S I E N T D U R A T I O N (μs )

100

5010015020025030001

1000

ENABLE TURN-ON DELAY

(MAX16053)

MAX16052/53 toc08

10μs/div EN 2V/div OUT 2V/div

ENABLE TURN-OFF DELAY

(MAX16053)

MAX16052/53 toc09

400ns/div

EN 2V/div

OUT 2V/div

MAX16052/MAX16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

_______________________________________________________________________________________7

EN LEAKAGE CURRENT vs. TEMPERATURE

TEMPERATURE (°C)

E N L E A K A G E C U R R E N T (n A )

110956580-105203550-25123456789100

-40125

EN LEAKAGE CURRENT vs. EN VOLTAGE

EN VOLTAGE (V)

E N L E A K A G E C U R R E N T (n A )

-8-6

-4-20246810

-10

Typical Operating Characteristics (continued)

(V CC = 3.3V and T A = +25°C, unless otherwise noted.)

M A X 16052/M A X 16053

High-Voltage, Adjustable

8_______________________________________________________________________________________

Detailed Description

The MAX16052/MAX16053 family of high-voltage,sequencing/supervisory circuits provide adjustable voltage monitoring for inputs down to 0.5V. These devices are ideal for use in power-supply sequencing,reset sequencing, and power-switching applications.Multiple devices can be cascaded for complex sequencing applications.

The MAX16052/MAX16053 perform voltage monitoring using a high-impedance input (IN) with an internally fixed 0.5V threshold. When the voltage at IN falls below 0.5V or when the enable input is deasserted (EN = low)OUT goes low. When V IN rises above 0.5V and the enable input is asserted (EN = high), OUT goes high after a capacitor-adjustable time delay.

With V IN above 0.5V, the enable input can be used to turn on or off the output. Table 1 details the output state depending on the various input and enable conditions.

CC The device operates with a V CC supply voltage from 2.25V to 16V. In order to maintain a 1.8% accurate threshold at IN, V CC must be above 2.25V. When V CC falls below the UVLO threshold, the output deasserts low. When V CC falls below 1.2V, the output state is not guaranteed. For noisy systems, connect a 0.1μF ceramic capacitor from V CC to GND as close to the device as possible.

Table 1. MAX16052/MAX16053

MAX16052/MAX16053

Monitor Input (IN)

Connect the center point of a resistive divider to IN to monitor external voltages (see R1 and R2 of Figure 4). IN has a rising threshold of V TH = 0.5V and a falling thresh-old of 0.495V (5mV hysteresis). When V IN rises above V TH and EN is high, OUT goes high after the adjustable t DELAY period. When V IN falls below 0.495V, OUT goes low after a 18μs delay. IN has a maximum input current of 60nA, so large value resistors are permitted without adding significant error to the resistive divider.

Adjustable Delay (CDELAY)

When V IN rises above V TH with EN high, the internal 250nA current source begins charging an external capacitor connected from CDELAY to GND. When the voltage at CDELAY reaches 1V, the output asserts (OUT goes high). When the output asserts, C CDELAY is immediately discharged. Adjust the delay (t DELAY ) from when V IN rises above V TH (with EN high) to OUT going high according to the equation:

where t DELAY is in seconds and C CDELAY is in Farads.

Enable Input (EN)

The MAX16052/MAX16053 offer an active-high enable input (EN). With V IN above V TH , drive EN high to force OUT high after the capacitor-adjustable delay time. The EN-to-OUT delay time (t PROP ) can be calculated from when EN goes above the EN threshold using the equation:

where t PROP is in seconds and C CDELAY is in Farads.Drive EN low to force OUT low within 300ns for the MAX16052 and within 400ns for the MAX16053.

Output (OUT)

The MAX16052 offers an active-high, open-drain output while the MAX16053 offers an active-high push-pull out-put. The push-pull output is referenced to V CC . The open-drain output requires a pullup resistor and can be pulled up to 28V.

Applications Information

Input Threshold

The MAX16052/MAX16053 monitor the voltage on IN with an external resistive divider (Figure 4). R1 and R2can have very high values to minimize current con-sumption due to low IN leakage currents (60nA max).Set R2 to some conveniently high value (200k Ωfor ±1%

additional variation in threshold, for example) and cal-culate R1 based on the desired monitored voltage using the following formula:

where V MONITOR is the desired monitored voltage and

V TH is the reset input threshold (0.5V).

Pullup Resistor Values (MAX16052 Only)

The exact value of the pullup resistor for the open-drain output is not critical, but some consideration should be made to ensure the proper logic levels when the device is sinking current. For example, if V CC = 2.25V and the pullup voltage is 28V, keep the sink current less than 0.5mA as shown in the Electrical Characteristics table.As a result, the pullup resistor should be greater than 56k Ω. For a 12V pullup, the resistor should be larger than 24k Ω. Note that the ability to sink current is depen-dent on the V CC supply voltage.

Ensuring a Valid OUT

Down to V CC = 0V (Push-Pull OUT)

In applications in which OUT must be valid down to V CC = 0V, add a pulldown resistor between OUT and GND for the push-pull output (MAX16053). The resistor sinks any stray leakage currents, holding OUT low (Figure 3). The value of the pulldown resistor is not criti-cal; 100k Ωis large enough not to load OUT and small enough to pull OUT to ground. The external pulldown

cannot be used with the open-drain OUT output.

t C s PROP CDELAY =××+()()

410146Ωμt C s DELAY CDELAY =××+()()

410306Ωμ

CC High-Voltage, Adjustable

Sequencing/Supervisory Circuits

_______________________________________________________________________________________9

M A X 16052/M A X 16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits 10______________________________________________________________________________________

Typical Application Circuits

Figures 4–6 show typical applications for the MAX16052/MAX16053. Figure 4 shows the MAX16052used with a p-channel MOSFET in an overvoltage pro-tection circuit. Figure 5 shows the MAX16053 in a low-voltage sequencing application using an n-channel MOSFET. Figure 6 shows the MAX16053 used in a mul-tiple output sequencing application.

Using an n-Channel Device

for Sequencing

In higher power applications, using an n-channel device reduces the loss across the MOSFET as it offers

a lower drain-to-source on-resistance. H owever, an n-channel MOSFET requires a sufficient V GS voltage to fully enhance it for a low R DS_ON . The application shown in Figure 5 shows the MAX16053 in a switch sequencing application using an n-channel MOSFET.Similarly, if a higher voltage is present in the system, the open-drain version can be used in the same manner.

Power-Supply Bypassing

In noisy applications, bypass V CC to ground with a 0.1μF capacitor as close to the device as possible. The additional capacitor improves transient immunity. For fast-rising V CC transients, additional capacitors may be required.

Figure 4. Overvoltage Protection Figure 5. Low-Voltage Sequencing Using an n-Channel MOSFET

MAX16052/MAX16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits

______________________________________________________________________________________11

Figure 6. Multiple Output Sequencing

Package Information

For the latest package outline information, go to https://www.wendangku.net/doc/0e15681368.html,/packages .Chip Information

PROCESS: BiCMOS

M A X 16052/M A X 16053

High-Voltage, Adjustable

Sequencing/Supervisory Circuits Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

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is a registered trademark of Maxim Integrated Products, Inc.