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MAX16011中文资料

General Description

The MAX16010–MAX16014 is a family of ultra-small, low-power, overvoltage protection circuits for high-voltage,high-transient systems such as those found in automotive,telecom, and industrial applications. These devices oper-ate over a wide 5.5V to 72V supply voltage range, making them also suitable for other applications such as battery stacks, notebook computers, and servers.

The MAX16010 and MAX16011 offer two independent comparators for monitoring both undervoltage and overvoltage conditions. These comparators offer open-drain outputs capable of handling voltages up to 72V.The MAX16010 features complementary enable inputs (EN/EN ), while the MAX16011 features an active-high enable input and a selectable active-high/low OUTB output.

The MAX16012 offers a single comparator and an inde-pendent reference output. The reference output can be directly connected to either the inverting or noninverting input to select the comparator output logic.

The MAX16013 and MAX16014 are overvoltage protec-tion circuits that are capable of driving two p-channel MOSF ETs to prevent reverse-battery and overvoltage conditions. One MOSF ET (P1) eliminates the need for external diodes, thus minimizing the input voltage drop.The second MOSFET (P2) isolates the load or regulates the output voltage during an overvoltage condition. The MAX16014 keeps the MOSFET (P2) latched off until the input power is cycled.

The MAX16010 and MAX16011 are available in small 8-pin TDFN packages, while the MAX16012/MAX16013/MAX16014 are available in small 6-pin TDFN packages.These devices are fully specified from -40°C to +125°C.

Applications

Automotive Industrial

48V Telecom/Server/Networking FireWire ?

Notebook Computers

Multicell Battery-Stack Powered Equipment

Features

?Wide 5.5V to 72V Supply Voltage Range

?Open-Drain Outputs Up to 72V (MAX16010/MAX16011/MAX16012)?Fast 2μs (max) Propagation Delay ?Internal Undervoltage Lockout

?p-Channel MOSFET Latches Off After an Overvoltage Condition (MAX16014)?Adjustable Overvoltage Threshold

?-40°C to +125°C Operating Temperature Range ?Small 3mm x 3mm TDFN Package

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits

________________________________________________________________Maxim Integrated Products 1

Ordering Information

Typical Operating Circuit

19-3693; Rev 2; 1/07

For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at https://www.wendangku.net/doc/b68951042.html,.

hysteresis, and “C” for 7.5% hysteresis.FireWire is a registered trademark of Apple Computer, Inc.

Pin Configurations appear at end of data sheet.

*Replace -T with +T for lead-free packages.**EP = Exposed pad.

M A X 16010–M A X 16014

Ultra-Small, Overvoltage Protection/Detection Circuits 2_______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V CC = 14V, T A = -40°C to +125°C, unless otherwise noted. Typical values are at 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 pins referenced to GND, unless otherwise noted.)

V CC .........................................................................-0.3V to +80V EN, EN , LOGIC...........................................-0.3V to (V CC + 0.3V)INA+, INB-, IN+, IN-, REF, SET..............................-0.3V to +12V OUTA, OUTB, OUT.................................................-0.3V to +80V GATE1, GATE2 to V CC ...........................................-12V to +0.3V GATE1, GATE2...........................................-0.3V to (V CC + 0.3V)Current Sink/Source (all pins).............................................50mA

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

6-Pin TDFN (derate 18.2mW/°C above +70°C).........1455mW 8-Pin TDFN (derate 18.2mW/°C above +70°C).........1455mW Operating Temperature Range .........................-40°C to +125°C Maximum Junction Temperature.....................................+150°C Storage Temperature Range.............................-60°C to +150°C Lead Temperature (soldering, 10s).................................+300°C

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits

_______________________________________________________________________________________3

ELECTRICAL CHARACTERISTICS (continued)

(V CC = 14V, T A = -40°C to +125°C, unless otherwise noted. Typical values are at T A = +25°C.) (Note 1)

A A A Typical Operating Characteristics

(V IN = 14V, T A = +25°C, unless otherwise noted.)

SUPPLY CURRENT vs. SUPPLY VOLTAGE

SUPPLY VOLTAGE (V)S U P P L Y C U R R E N T (μA )

15202530354010

75SUPPLY CURRENT vs. TEMPERATURE

TEMPERATURE (°C)

S U P P L Y C U R R E N T (μA )110956580-105203550-2526.0526.1026.1526.2026.2526.3026.3526.4026.4526.5026.00

-40125

GATE VOLTAGE vs. SUPPLY VOLTAGE

SUPPLY VOLTAGE (V)

G A T E V O L T A G E (V )

6555453525151020304050600

575

M A X 16010–M A X 16014

Ultra-Small, Overvoltage Protection/Detection Circuits 4_______________________________________________________________________________________

Typical Operating Characteristics (continued)

(V IN = 14V, T A = +25°C, unless otherwise noted.)

UVLO THRESHOLD vs. TEMPERATURE

TEMPERATURE (°C)

U V L O T H R E S H O L D (V )

110956580-105203550-254.64.74.84.95.05.15.25.35.45.54.5

-40125

INA+/INB-/SET THRESHOLD

vs. TEMPERATURE

TEMPERATURE (°C)

I N A +/I N B -/S E T T H R E S H O L D (V )

110956580-105203550-251.211.221.231.241.251.261.271.281.291.30

1.20

-40125

GATE VOLTAGE vs. TEMPERATURE

TEMPERATURE (°C)

(V C C - V G A T E ) (V )

110956580-105203550-259.19.29.39.49.59.69.79.89.910.0

9.0

-40125

STARTUP WAVEFORM

(R OUT = 100?, C IN = 10μF, C OUT = 10nF)

MAX16010 toc07

V GATE 5V/div V OUT 10V/div

V CC 10V/div

200μs/div

STARTUP WAVEFORM

(R OUT = 100?, C IN = 10μF, C OUT = 10nF)

V GATE 10V/div

V OUT 10V/div

V CC 1V/div

20μs/div

V EN = 0 TO 2V

OVERVOLTAGE SWITCH FAULT

(R OUT = 100?, C IN = 80μF, C OUT = 10nF)

V GATE 20V/div

V OUT 20V/div

V CC 20V/div 1ms/div

V IN = 12V TO 40V, TRIP THRESHOLD = 28V

OVERVOLTAGE LIMIT

(R OUT = 100?, C IN = 80μF, C OUT = 10nF)

V GATE 20V/div

V OUT 20V/div

V CC 20V/div 1ms/div

V IN = 12V TO 40V

TRIP THRESHOLD = 28V

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits

Pin Description

M A X 16010–M A X 16014

Detailed Description

The MAX16010–MAX16014 is a family of ultra-small, low-power, overvoltage protection circuits for high-voltage,high-transient systems such as those found in automo-tive, telecom, and industrial applications. These devices operate over a wide 5.5V to 72V supply voltage range,making them also suitable for other applications such as battery stacks, notebook computers, and servers.

The MAX16012 offers a single comparator and an inde-pendent reference output. The reference output can be directly connected to either the inverting or noninvert-ing input to select the comparator output logic.

The MAX16013 and MAX16014 are overvoltage protec-tion circuits that are capable of driving two p-channel MOSF ETs to prevent reverse battery and overvoltage conditions. One MOSF ET (P1) eliminates the need for external diodes, thus minimizing the input voltage drop.While the second MOSFET (P2) isolates the load or reg-ulates the output voltage during an overvoltage condi-tion. The MAX16014 keeps the MOSF ET (P2) latched off until the input power is cycled.

Voltage Monitoring

The MAX16010/MAX16011 include undervoltage and overvoltage comparators for window detection (see Figure 1). OUT_ asserts high when the monitored volt-age is within the selected “window.” OUTB asserts low when the monitored voltage falls below the lower (V TRIPLOW ) limit of the window, or OUTA asserts low if the monitored voltage exceeds the upper limit (V TRIPHIGH ). The application in F igure 1 shows OUT_enabling the DC-DC converter when the monitored volt-age is in the selected window.

The resistor values R1, R2, and R3 can be calculated as follows:

TOTAL Use the following steps to determine the values for R1,R2, and R3.

1)Choose a value for R TOTAL , the sum of R1, R2, and R3. Because the MAX16010/MAX16011 have very high input impedance, R TOTAL can be up to 5M ?.2)Calculate R3 based on R TOTAL and the desired upper trip point:

3)Calculate R2 based on R TOTAL , R3, and the desired lower trip point:

4)Calculate R1 based on R TOTAL , R3, and R2:

R1 = R TOTAL - R2 - R3

The MAX16012 has both inputs of the comparator avail-able with an integrated 1.30V reference (REF). When the voltage at IN+ is greater than the voltage at IN- then OUT goes high. When the voltage at IN- is greater than the voltage at IN+ then OUT goes low. Connect REF to IN+or IN- to set the reference voltage value. Use an external resistive divider to set the monitored voltage threshold.

Ultra-Small, Overvoltage Protection/Detection Circuits 6

_______________________________________________________________________________________

The MAX16013/MAX16014 can be configured as an overvoltage switch controller to turn on/off a load (see the Typical Application Circuit ). When the programmed overvoltage threshold is tripped, the internal fast com-parator turns off the external p-channel MOSF ET (P2),pulling GATE2 to V CC to disconnect the power source from the load. When the monitored voltage goes below the adjusted overvoltage threshold, the MAX16013enhances GATE2, reconnecting the load to the power source (toggle ENABLE on the MAX16014 to reconnect the load). The MAX16013 can be configured as an overvoltage limiter switch by connecting the resistive divider to the load instead of V CC (F igure 3). See the Overvoltage Limiter section.

Supply Voltage

Connect a 5.5V to 72V supply to V CC for proper opera-tion. For noisy environments, bypass V CC to GND with a 0.1μF or greater capacitor. When V CC falls below the UVLO voltage the following states are present (Table 1).

Hysteresis

Hysteresis adds noise immunity to the voltage monitors and prevents oscillation due to repeated triggering when the monitored voltage is near the threshold trip voltage. The hysteresis in a comparator creates two trip points: one for the rising input voltage (V TH+) and one for the falling input voltage (V TH-). These thresholds are shown in Figure 4.

Enable Inputs (EN or EN )

The MAX16011 offers an active-high enable input (EN),while the MAX16010 offers both an active-high enable input (EN) and active-low enable input (EN ). F or the MAX16010, drive EN low or EN high to force the output low. When the device is enabled (EN = high and EN =low) the state of OUTA and OUTB depends on INA+and INB- logic states.

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits

_______________________________________________________________________________________

Table 1. UVLO State (V CC < V UVLO )

M A X 16010–M A X 16014

OUTB low when LOGIC = low, and OUTB high when LOGIC = high. When the device is enabled (EN = high)the state of OUTA and OUTB depends on the INA+,INB-, and LOGIC input (see Table 2).

F or the MAX16013/MAX16014, drive EN low to pull GATE2 to V CC , turning off the p-channel MOSFET (P2).When the device is enabled (EN = high), GATE2 is pulled to the greater of (V CC - 10V) or GND turning on the external MOSFET (P2).

Applications Information

Load Dump

Most automotive applications are powered by a multi-cell, 12V lead-acid battery with a voltage between 9V and 16V (depending on load current, charging status,temperature, battery age, etc.). The battery voltage is distributed throughout the automobile and is locally regulated down to voltages required by the different system modules. Load dump occurs when the alterna-tor is charging the battery and the battery becomes disconnected. Power in the alternator inductance flows into the distributed power system and elevates the volt-age seen at each module. The voltage spikes have rise times typically greater than 5ms and decays within sev-eral hundred milliseconds but can extend out to 1s or more depending on the characteristics of the charging system. These transients are capable of destroying sensitive electronic equipment on the first fault event.The MAX16013/MAX16014 provide the ability to dis-connect the load from the charging system during an overvoltage condition to protect the module. In addi-tion, the MAX16013 can be configured in a voltage-lim-iting mode. This allows continuous operation while providing overvoltage protection. See the Overvoltage Limiter section.

Input Transients Clamping

When the external MOSF ET is turned off during an overvoltage occurrence, stray inductance in the power path may cause voltage ringing to exceed the MAX16013/MAX16014 absolute maximum input (V CC )supply rating. The following techniques are recom-mended to reduce the effect of transients:?Minimize stray inductance in the power path using

wide traces, and minimize loop area including the power traces and the return ground path.?Add a zener diode or transient voltage suppresser

(TVS) rated below V CC absolute maximum rating (Figure 3).

Overvoltage Limiter

When operating in overvoltage-limiter mode, the MAX16013 drives the external p-channel MOSFET (P2),resulting in the external MOSFET operating as a voltage regulator.

During normal operation, GATE2 is pulled to the greater of (V CC - 10V) or GND. The external MOSF ET’s drain voltage is monitored through a resistor-divider between the P2 output and SET. When the output voltage rises above the adjusted overvoltage threshold, an internal comparator pulls GATE2 to V CC . When the monitored voltage goes below the overvoltage threshold, the p-channel MOSF ET (P2) is turned on again. This process continues to keep the voltage at the output reg-ulated to within approximately a 5% window. The output voltage is regulated during the overvoltage transients and the MOSFET (P2) continues to conduct during the overvoltage event, operating in switched-linear mode.Caution must be exercised when operating the MAX16013 in voltage-limiting mode for long durations due to the MOSF ET’s power dissipation consideration (see the MOSFET Selection and Operation section).

MOSFET Selection and Operation

(MAX16013 and MAX16014)

Most battery-powered applications must include reverse voltage protection. Many times this is implemented with a diode in series with the battery. The disadvantage in using a diode is the forward voltage drop of the diode,which reduces the operating voltage available to down-stream circuits (V LOAD = V BATTERY - V DIODE ). The MAX16013 and MAX16014 include high-voltage GATE1drive circuitry allowing users to replace the high-voltage-drop series diode with a low-voltage-drop MOSF ET device (as shown in the Typical Operating Circuit and Figure 3). The forward voltage drop is reduced to I LOAD x R DS-ON of P1. With a suitably chosen MOSF ET, the voltage drop can be reduced to millivolts.

Ultra-Small, Overvoltage Protection/Detection Circuits 8_______________________________________________________________________________________

Table 2. MAX16011 Output Logic

In normal operating mode, internal GATE1 output cir-cuitry enhances P1 to a 10V gate-to-source (V GS) for 11V < V CC< 72V. The constant 10V enhancement ensures P1 operates in a low R DS-ON mode, but the gate-source junction is not overstressed during high-battery-voltage application or transients (many MOSFET devices specify a ±20V V GS absolute maximum). As V CC drops below 10V GATE1 is limited to GND, reduc-ing P1 V GS to V CC- GND. In normal operation the P1 power dissipation is very low:

P1 = I LOAD2x R DS-ON

During reverse-battery applications, GATE1 is limited to GND and the P1 gate-source junction is reverse biased. P1 is turned off and neither the MAX16013/ MAX16014 nor the load circuitry is exposed to the reverse-battery voltage. Care should be taken to place P1 (and its internal drain-to-source diode) in the correct orientation for proper reverse battery operation.

P2 protects the load from input overvoltage conditions. During normal operating modes (the monitored voltage is below the adjusted overvoltage threshold), internal GATE2 output circuitry enhances P2 to a 10V gate-to-source (V GS) for 11V < V CC< 72V. The constant 10V enhancement ensures P2 operates in a low R DS-ON mode but the gate-to-source junction is not over-stressed during high-battery-voltage applications (many pFET devices specify a ±20V V GS absolute max-imum). As V CC drops below 10V, GATE2 is limited to GND, reducing P2 V GS to V CC- GND. In normal opera-tion, the P2 power dissipation is very low:

P2 = I LOAD2x R DS-ON During overvoltage conditions, P2 is either turned com-pletely off (overvoltage-switch mode) or cycled off-on-

off (voltage-limiter mode). Care should be taken to

place P2 (and its internal drain-to-source diode) in the correct orientation for proper overvoltage protection operation. During voltage-limiter mode, the drain of P2

is limited to the adjusted overvoltage threshold, while

the battery (V CC) voltage rises. During prolonged over-voltage events, P2 temperature can increase rapidly

due to the high power dissipation. The power dissipat-

ed by P2 is:

P2 = V DS-P2 x I LOAD

= (V CC- V OV-ADJUSTED) x I LOAD

where V CC~ V BATTERY and V OV-ADJUSTED is the desired

load limit voltage. For prolonged overvoltage events with

high P2 power dissipation, proper heatsinking is required.

Adding External Pullup Resistors

It may be necessary to add an external resistor from

V CC to GATE1 to provide enough additional pullup capability when the GATE1 input goes high. The GATE_ output can only source up to 1μA current. If the source current is less than 1μA, no external resistor

may be necessary. However, to improve the pullup capability of the GATE_ output when it goes high, con-

nect an external resistor between V CC and the GATE_.

The application shows a 2M?resistor, which is large enough not to impact the sinking capability of the GATE_ (during normal operation) while providing enough pullup during an overvoltage event. With an

11V (worst case) V CC-to-gate clamp voltage and a sinking current of 75μA, the smallest resistor should be

11V/75μA, or about 147k?. However, since the GATE_

is typically low most of the time, a higher value should

be used to reduce overall power consumption.

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits _______________________________________________________________________________________9

M A X 16010–M A X 16014

Ultra-Small, Overvoltage Protection/Detection Circuits 10

MAX16010–MAX16014

Ultra-Small, Overvoltage Protection/

Detection Circuits

______________________________________________________________________________________11

Chip Information

PROCESS: BiCMOS

Pin Configurations

M A X 16010–M A X 16014

Ultra-Small, Overvoltage Protection/Detection 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.

12____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600?2007 Maxim Integrated Products

is a registered trademark of Maxim Integrated Products, Inc.

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to https://www.wendangku.net/doc/b68951042.html,/packages .)

Revision History

Pages changed at Rev 2: 1, 10, 12