MAX16914AUB/V+T - Maxim Integrated

General Description

The MAX16914/MAX16915 low-quiescent-current over-

voltage and reverse-battery protection controllers are

designed for automotive and industrial systems that

must tolerate high-voltage transient and fault conditions.

These conditions include load dumps, voltage dips, and

reversed input voltages. The controllers monitor the input

voltage on the supply line and control two external pFETs

to isolate the load from the fault condition. The external

pFETs are turned on when the input supply exceeds 4.5V

and stay on up to the programmed overvoltage threshold.

During high-voltage fault conditions, the controllers regu-

late the output voltage to the set upper threshold voltage

(MAX16915), or switch to high resistance (MAX16914) for

the duration of the overvoltage transient to prevent dam-

age to the downstream circuitry. The overvoltage event is

indicated through an active-low, open-drain output, OV.

The reverse-battery pFET behaves as an ideal diode,

minimizing the voltage drop when forward biased. Under

reverse bias conditions, the pFET is turned off, prevent-

ing a downstream tank capacitor from being discharged

into the source.

Shutdown control turns off the IC completely, disconnect-

ing the input from the output and disconnecting TERM

from its external resistor-divider to reduce the quiescent

current to a minimum.

Both devices are available in a 10-pin μMAX® pack-

age and operate over the automotive -40°C to +125°C

temperature range.

Applications

Industrial

Benets and Features

●Architecture Replaces Protection Diodes Reducing

the Forward Voltage, Allowing Operation During

Cold-Crank Conditions

• Transient Voltage Protection Up to +44V and -75V

• Low-Voltage Drop when Used with Properly Sized

External pFETs

• 4.5V to 19V Input-Voltage Operation

●Ideal Diode Reverse-Battery Protection Supports

Down to -75V to Protect System During Negative-

Voltage Transients

• Back-Charge Prevention Avoids Discharging

Downstream Tank Capacitance

●Overvoltage Protection Enables System to Survive

Up to a +44V Load Dump

• Overvoltage Indicator

• Thermal-Overload Protection

●Low Operating Current Meets Stringent Module

Specifications While Maintaining System Protection

• 29µA Low Operating Current

• 6µA Low Shutdown Current

Pin Conguration

Typical Operating Circuit

µMAX is a registered trademark of Maxim Integrated Products, Inc.

19-4964; Rev 3; 2/15

GATE2

SENSE OUT

TERM

SETSHDN

SENSE IN

GATE1

VCC

MAX16914

MAX16915

TOP VIEW

GNDOV

VCC

VBATT VOUT

P2P1

GATE1

SENSE IN

SHDN

OFF

MAX16914

MAX16915

GATE2

SENSE OUT

TERM

SET

GND

Ordering Information appears at end of data sheet.

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-

tion 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, SENSE OUT, TERM, SHDN, OV to GND for

P 400ms ............................................................. -0.3V to +44V

VCC, SENSE OUT, TERM, SHDN, OV to GND

for P 90s .............................................................-0.3V to +28V

VCC, SENSE OUT, TERM, SHDN, OV to GND .....-0.3V to +20V

SENSE IN to GND for P 2ms ..................................-75V to +44V

SENSE IN to GND for P 90s .................................. -18V to +44V

SENSE IN to GND .................................................-0.3V to +20V

GATE1, GATE2 to VCC ..........................................-16V to +0.3V

GATE1, GATE2 to GND ........................... -0.3V to (VCC + 0.3V)

SET to GND .............................................................-0.3V to +8V

Continuous Power Dissipation (TA = +70NC)

10-Pin FMAX (derate 8.8mW/NC above TA = +70NC)

(Note 1) .......................................................................707mW

Operating Temperature Range ........................ -40NC to +125NC

Junction Temperature .....................................................+150NC

Storage Temperature Range ............................ -65NC to +150NC

Lead Temperature (soldering, 10s) ................................+300NC

Electrical Characteristics

(VCC = 14V, CGATE1 = 32nF, CGATE2 = 32nF, SHDN = high, TA = -40NC to +125NC, unless otherwise noted. Typical values

are at TA = +25NC.) (Note 2)

Absolute Maximum Ratings

Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer

board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Operating Voltage Range VCC (Note 3) 4.5 19 V

Shutdown Supply Current

(ISENSE IN + ISENSE OUT + IOV +

ISHDN + IVCC)

ISHDN

SHDN = low,

VSENSE OUT = 0V,

VTERM = 0V

TA = +25NC6.0 12

TA = +85NC (Note

3) 6.1 12

TA = +125NC

(Note 3) 6.2 12

Quiescent Supply Current

(ISENSE IN + ISENSE OUT + IOV +

ISHDN + IVCC)

IQSHDN = high

TA = +25NC29 53

TA = +85NC (Note

3) 30 55

TA = +125NC

(Note 3) 31 57

VCC Undervoltage Lockout VUVLO VCC rising, VSET = 1V , SHDN = high 4.06 4.35 V

VCC Undervoltage-Lockout

Hysteresis 8 %

SET Threshold Voltage VSETTH VSET rising -3% +1.20 +3% V

SET Threshold Voltage

Hysteresis VSETHY 4 %

SET Input Current ISET VSET = 1V 0.02 0.2 FA

SHDN Low Threshold VSHDNL 0.4 V

SHDN High Threshold VSHDNH 1.4 V

SHDN Pulldown Current ISHDN VSHDN = 14V, internally pulled to GND 0.5 1.0 FA

VCC to GATE Output Low

Voltage VGVCC1 VCC = 14V 6.25 7.5 8.5 V

VCC to GATE Clamp Voltage VGVCC2 VCC = 42V 14 V

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

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Electrical Characteristics (continued)

(VCC = 14V, CGATE1 = 32nF, CGATE2 = 32nF, SHDN = high, TA = -40NC to +125NC, unless otherwise noted. Typical values

are at TA = +25NC.) (Note 2)

Note 2: All parameters are production tested at TA = +25NC. Limits over the operating temperature range are guaranteed by

design and characterization.

Note 3: Guaranteed by design and characterization.

Note 4: The back-charge voltage, VBC, is defined as the voltage at SENSE OUT minus the voltage at SENSE IN.

Note 5: Defined as the time from when VBC exceeds VBCTH (25mV typ) to when VGATE1 exceeds VCC - 3.5V.

Note 6: Defined as the time from when VBC falls below VBCTH - 50mV to when VGATE1 falls below VCC - 3.5V.

Note 7: Defined as the time from when VSET exceeds VSETTH (1.20V typ) to when VGATE2 exceeds VCC - 3.5V.

Note 8: Defined as the time from when VSET falls below VSETTH - 5% (1.14V typ) to when VGATE2 falls below VCC - 3.5V.

Note 9: The external pFETs can turn on tSTART after the IC is powered up and all input conditions are valid.

Note 10: Defined as the time from when VCC exceeds the undervoltage-lockout threshold (4.3V max) to when VGATE1 and VGATE2

fall below 1V.

Note 11: Defined as the time from when VCC falls below VSENSE OUT - 25mV to when VGATE1 reaches VCC - 1.75V.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

TERM On-Resistance RTERM SHDN = high 150 500 I

TERM Output Current ITERM SHDN = low, VTERM = 0V 1.0 FA

Back-Charge Voltage Fault

Threshold VBCTH VSENSE OUT = 14V (Note 4) 18 25 32 mV

Back-Charge Voltage Threshold

Hysteresis VBCHY VSENSE OUT = 14V 50 mV

Back-Charge Turn-Off Time

(GATE1) tBC

VCC = 9.5V, VSENSE IN = 9V,

VSENSE OUT stepped from 4.9V to 9.5V

(Note 5)

6 10 Fs

Back-Charge Recovery Time

(GATE1) tBCREC

VCC = 9.5V, VSENSE IN = 9V,

VSENSE OUT stepped from 9.5V to 4.9V

(Note 6)

18 30 Fs

GATE2 Turn-Off Time VCC = 9.5V, VSET rising from 1V to

1.5V (Note 7) 3Fs

GATE2 Turn-On Time VCC = 9.5V, VSET falling from 1.5V to

1V (Note 8) 20 Fs

Startup Response Time

(VSHDN Rising) tSTART1 VCC = 9.5V, from VSHDN rising to

VGATE_ falling (Note 9) 100 Fs

Startup Response Time

(VCC Rising) tSTART2 VCC rising from 2V to 4.5V, SHDN =

high (Note 10) 0.150 ms

Reverse-Battery Voltage Turn-Off

Time/UVLO Turn-Off Time tREVERSE

VCC and VSENSE IN falling from 4.25V

to 3.25V, VSENSE OUT = 4.25V

(Note 11)

30 Fs

Thermal-Shutdown Temperature +170 NC

Thermal-Shutdown Hysteresis 20 NC

OV Output Low Voltage VOVBL ISINK = 600FA0.4 V

OV Open-Drain Leakage Current IOVB VSET = 1.0V 1.0 FA

SENSE IN Input Current ISENSE IN VSHDN = 0/14V 1 5 FA

SENSE OUT Input Current ISENSE OUT VSHDN = 0/14V 2 5 FA

SET to OV Output Low

Propagation Delay tOVBPD VCC = 9.5V, VSET rising from 1V to

1.5V to VOV falling 3Fs

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

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SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX16914 toc01

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

17.012.0 14.59.57.0

4.5 19.0

TERM = OPEN

SHDN = HIGH

SET = 0V

NO LOAD

MAX16914

MAX16915

SUPPLY CURRENT

vs. TEMPERATURE

MAX16914 toc02

TEMPERATURE (NC)

SUPPLY CURRENT (FA)

11085603510-15

-40 125

TERM = OPEN

SHDN = HIGH

SET = 0V, VCC = 14V

NO LOAD

MAX16915

MAX16914

SHUTDOWN SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX16914 toc03

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (FA)

17.014.512.09.57.0

4.5 19.0

SHDN = LOW

SET = 0V

MAX16915

MAX16914

UVLO THRESHOLD

vs. TEMPERATURE

MAX16914 toc04

TEMPERATURE (NC)

UVLO TRESHOLD (V)

11085-15 10 35 60

3.6

3.7

3.8

3.9

4.0

4.1

4.2

4.3

3.5

-40 125

RISING

FALLING

SET THRESHOLD

vs. TEMPERATURE

MAX16914 toc05

TEMPERATURE (NC)

SET THRESHOLD (V)

11085603510-15

1.15

1.20

1.25

1.10

-40 125

RISING

FALLING

POWER-UP RESPONSE

MAX16914 toc06

40µs/div

VCC

10V/div

VOUT

10V/div

VGATE1

10V/div

VGATE2

10V/div

22µF INPUT AND OUTPUT CAPACITOR,

ROUT = 100I, SHDN = HIGH

STARTUP FROM

SHUTDOWN RESPONSE

MAX16914 toc07

20µs/div

100µF INPUT CAPACITOR, 122µF

OUTPUT CAPACITOR, ROUT = 100I

VSHDN

2V/div

VOUT

10V/div

VGATE1

10V/div

14V

VGATE2

10V/div

OVERVOLTAGE LIMITER RESPONSE

(MAX16915)

MAX16914 toc08

400µs/div

100µF INPUT CAPACITOR, 22µF

OUTPUT CAPACITOR, ROUT = 100I

COV = 10nF

VCC = 14V TO 30V

TRIP THRESHOLD = 22V

VCC

20V/div

VOUT

20V/div

14V

30V

VGATE2

20V/div

VOV

20V/div

OVERVOLTAGE SWITCH-OFF

RESPONSE (MAX16914)

MAX16914 toc09

1.0µs/div

100µF INPUT CAPACITOR, 22µF

OUTPUT CAPACITOR, ROUT = 100I

VCC

10V/div

VOUT

10V/div

14V

30V

14V

20V

VGATE2

20V/div

VOV

20V/div

VCC = 14V TO 30V

TRIP THRESHOLD = 22V

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

Maxim Integrated

│

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Typical Operating Characteristics

(VCC = 14V, VSHDN = 14V, MAX16914/MAX16915 Evaluation Kit, TA = +25NC, unless otherwise noted.)

Pin Description

Typical Operating Characteristics (continued)

(VCC = 14V, VSHDN = 14V, MAX16914/MAX16915 Evaluation Kit, TA = +25NC, unless otherwise noted.)

PIN NAME FUNCTION

1 VCC Positive Supply Input Voltage. Bypass VCC to GND with a 0.1FF or greater ceramic capacitor.

2 GATE1 Gate-Driver Output. Connect GATE1 to the gate of an external p-channel FET pass switch to pro-

vide low drain-to-source voltage drop, reverse voltage protection, and back-charge prevention.

3SENSE IN Differential Voltage Sense Input (Input Side of IC). Used with SENSE OUT to provide back-charge

prevention when the SENSE IN voltage falls below the SENSE OUT voltage by 25mV.

4SHDN

Active-Low Shutdown/Wake Input. Drive SHDN high to turn on the voltage detectors. GATE2 is

shorted to VCC when SHDN is low. SHDN is internally pulled to GND through a 0.5FA current sink.

Connect SHDN to VCC for always-on operation.

5OV Open-Drain Overvoltage Indicator Output. Connect a pullup resistor from OV to a positive supply

such as VCC. OV is pulled low when the voltage at SET exceeds the internal threshold.

6 GND Ground

7 SET

Controller Overvoltage Threshold Programming Input. Connect SET to the center of an external

resistive divider network between TERM and GND to adjust the desired overvoltage switch-off or

limiter threshold.

8 TERM

Voltage-Divider Termination Output. TERM is internally connected to SENSE OUT in the MAX16915

and to VCC in the MAX16914. TERM is high impedance when SHDN is low, forcing the current to

zero in the resistor-divider connected to TERM.

9SENSE OUT Differential Voltage Sense Input (Output Side Of IC). Used with SENSE IN to provide back-charge

prevention when the SENSE IN voltage falls below the SENSE OUT voltage by 25mV.

10 GATE2

Gate-Driver Output. Connect GATE2 to the gate of an external p-channel FET pass switch. GATE2

is driven low during normal operation and quickly regulated or shorted to VCC during an overvolt-

age condition. GATE2 is shorted to VCC when SHDN is low.

BACK-CHARGE RESPONSE

MAX16914 toc10

1.0µs/div

2.2µF INPUT CAPACITOR, 400I

INPUT RESISTOR, 22µF OUTPUT CAPACITOR

VCC

5V/div

VOUT

5V/div

VGATE1

5V/div

VCC - VGATE_

vs. INPUT VOLTAGE

MAX16914 toc11

SUPPLY VOLTAGE (V)

GATE DRIVE VOLTAGE (V)

40.536.027.0 31.513.5 18.0 22.59.0

1.5

3.0

4.5

6.0

7.5

9.0

10.5

12.0

13.5

15.0

4.5 44.0

GATE1

GATE2

SET = GND

SHDN = HIGH

GATE-DRIVE VOLTAGE

vs. TEMPERATURE

MAX16914 toc12

TEMPERATURE (NC)

GATE-DRIVE VOLTAGE (V)

11085603510-15

6.3

6.4

6.5

6.6

6.2

-40 125

GATE1

GATE2

VCC = 14V

SET = GND

SHDN = HIGH

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

Maxim Integrated

│

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Detailed Description

The MAX16914/MAX16915 are ultra-small, low-quies-

cent, high load-current, overvoltage-protection circuits

for automotive or industrial applications. These devices

monitor the input and output voltages and control two

p-channel MOSFETs to protect downstream loads from

reverse-battery, overvoltage, and high-voltage transient

conditions and prevent downstream tank capacitors from

discharging into the source (back-charging).

One MOSFET (P1) eliminates the need for external diodes,

thus minimizing the input voltage drop and provides

back-charge and reverse-battery protection. The second

MOSFET (P2) isolates the load or regulates the output

voltage during an overvoltage condition. These ICs allow

system designers to size the external p-channel MOSFET

to their load current, voltage drop, and board size.

Overvoltage Switch-Off Controller

(MAX16914)

In the MAX16914, the input voltage is monitored (TERM

is internally shorted to VCC—see the Functional Diagram)

making the device an overvoltage switch-off controller. As

the VCC voltage rises, and the programmed overvoltage

threshold is tripped, the internal fast comparator turns

off the external p-channel MOSFET (P2), pulling GATE2

to VCC to disconnect the power source from the load.

When the monitored voltage goes below the adjusted

overvoltage threshold, the MAX16914 enhances GATE2,

reconnecting the load to the power source.

Functional Diagram

REG

GATE2

1.20V

GATE1

SENSE IN

SHDN

VCC

SENSE OUT

SET

TERM

GND

TERM

SWITCH

TO VCC FOR

MAX16914

TO SENSE OUT

FOR MAX16915

BANDGAP

BIAS

OV1

MAX16914

MAX16915

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

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Overvoltage Limiter

Controller (MAX16915)

In the MAX16915, TERM is internally connected to

SENSE OUT (see the Functional Diagram) allowing the

IC to operate in voltage-limiter mode.

During normal operation, GATE2 is pulled low to fully

enhance the MOSFET. The external MOSFET’s drain

voltage is monitored through a resistor-divider between

TERM, SET, and GND. When the output voltage rises

above the adjusted overvoltage threshold, an internal

comparator pulls GATE2 to VCC turning off P2. When the

monitored voltage goes below the overvoltage thresh-

old (-4% hysteresis), the p-channel MOSFET (P2) is

turned on again. During a continuous overvoltage con-

dition, MOSFET (P2) cycles on and off (between the

overvoltage threshold and the hysteresis), generating

a sawtooth waveform with a frequency dependent on

the load capacitance and load current. This process

continues to keep the voltage at the output regulated to

within approximately a 4% window. The output voltage is

regulated during the overvoltage transients and MOSFET

(P2) continues to conduct during the overvoltage event,

operating in switched-linear mode.

Caution must be exercised when operating the MAX16915

in voltage-limiting mode for long durations due to the

MOSFET’s power-dissipation consideration (see the

MOSFET Selection section).

Shutdown

The MAX16914/MAX16915 feature an active-low shut-

down input (SHDN). Drive SHDN low to switch off FET

(P2), disconnecting the input from the output, thus

placing the IC in low-quiescent-current mode. Reverse-

battery protection is still maintained.

Reverse-Battery Protection

The MAX16914/MAX16915 feature reverse-battery pro-

tection to prevent damage to the downstream circuitry

caused by battery reversal or negative transients. The

reverse-battery protection blocks the flow of current into

the downstream load and allows the circuit designer to

remove series-protection diodes.

Back-Charge Switch-Off

The MAX16914/MAX16915 monitor the input-to-output

differential voltage between SENSE IN and SENSE OUT.

It turns off the external FET (P1) when (VSENSE OUT -

VSENSE IN) > 25mV (see Figure 1) to prevent discharging

of a downstream tank capacitor into the battery supply

during an input voltage drop, such as a cold-crank con-

dition or during a superimposed sinusoidal voltage on

top of the supply voltage. It turns on the FET (P1) again

if the back-charge voltage threshold hysteresis of 50mV

is satisfied.

Figure 1. Back-Charge Turn-Off Time

IOUT

VOUT - VBATT = 0V

VOUT - VBATT = 50mV

tBC = 10µs (max)

VBATT = 9V

50% (25mV)

50%

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

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Overvoltage Indicator Output (OV)

The MAX16914/MAX16915 include an active-low,

open-drain overvoltage-indicator output (OV). For the

MAX16914, OV asserts low when VCC exceeds the pro-

grammed overvoltage threshold. OV deasserts when the

overvoltage condition is over.

For the MAX16915, OV asserts if VOUT exceeds the

programmed overvoltage threshold. OV deasserts when

VOUT drops 4% (typ) below the overvoltage threshold

level. If the overvoltage condition continues, OV may

toggle with the same frequency as the overvoltage limiter

FET (P2). If the P2 device is turned on for a very short

period (less than tOVBPD), the OV pin may not toggle. To

obtain a logic-level output, connect a 45kI pullup resis-

tor from OV to a system voltage less than 44V. A capaci-

tor connected from OV to GND helps extend the time that

the logic level remains low.

Applications Information

Load Dump

Most automotive applications run off a multicell “12V”

lead-acid battery with a nominal voltage that swings

between 9V and 16V (depending on load current, charg-

ing status, temperature, battery age, etc.). The battery

voltage is distributed throughout the automobile and is

locally regulated down to voltages required by the differ-

ent system modules. Load dump occurs when the alter-

nator is charging the battery and the battery becomes

disconnected. The alternator voltage regulator is tem-

porarily driven out of control. Power from the alternator

flows into the distributed power system and elevates the

voltage seen at each module. The voltage spikes have

rise times typically greater than 5ms and decays within

several hundred milliseconds but can extend out to 1s

or more depending on the characteristics of the charg-

ing system. These transients are capable of destroying

sensitive electronic equipment on the first “fault event.”

Setting Overvoltage Thresholds

TERM and SET provide an accurate means to set the

overvoltage level for the MAX16914/MAX16915. Use a

resistive divider to set the desired overvoltage condition

(see the Typical Operating Circuit). VSET has a rising

1.20V threshold with a 4% falling hysteresis. Begin by

selecting the total end-to-end resistance:

RTOTAL = R1 + R2

For high accuracy, choose RTOTAL to yield a total current

equivalent to a minimum 100 x ISET where ISET is the

input bias current at SET.

For example:

With an overvoltage threshold (VOV) set to 20V, RTOTAL

< 20V/(100 x ISET), where ISET = 1FA (max).

RTOTAL < 200kI

Use the following formula to calculate R2:

R2 = (VTH x RTOTAL)/VOV

where VTH is the 1.20V SET rising threshold and VOV is

the desired overvoltage threshold.

Then, R2 = 12.0kI.

Use the nearest standard-value resistor lower than the

calculated value. A lower value for total resistance dissi-

pates more power but provides slightly better accuracy.

To determine R1:

RTOTAL = R2 + R1

Then, R1 = 188kI.

Use the nearest standard-value resistor lower than the

calculated value. A lower value for total resistance dissi-

pates more power but provides slightly better accuracy.

MOSFET Selection

Output p-Channel MOSFET (P2)

Select the external output MOSFET according to the

application current level. The MOSFET’s on-resistance

(RDS(ON)) should be chosen low enough to have a

minimum voltage drop at full load to limit the MOSFET

power dissipation. Determine the device power rating to

accommodate an overvoltage fault when operating the

MAX16915 in overvoltage-limiting mode. During normal

operation for either IC, the external MOSFET dissipates

little power. The power dissipated in the MOSFET during

normal operation is:

PNORM = ILOAD2 x RDS(ON)

where PNORM is the power dissipated in the MOSFET

in normal operation, ILOAD is the output load current,

and RDS(ON) is the drain-to-source resistance of the

MOSFET. Worst-case power dissipation in the output

MOSFET occurs during a prolonged overvoltage event

when operating the MAX16915 in voltage-limiting mode.

The power dissipated across the MOSFET is as follows:

POVLO = VDS x ILOAD

where POVLO is the power dissipated in the MOSFET in

overvoltage-limiting operation, VDS is the voltage across

the MOSFET’s drain and source, and ILOAD is the load

current.

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

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Reverse-Polarity Protection MOSFET (P1)

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 (VLOAD = VBATTERY - VDIODE).

The MAX16914/MAX16915 include high-voltage GATE1

drive circuitry allowing users to replace the high-voltage

drop series diode with a low-voltage-drop MOSFET

device (as shown in the Typical Operating Circuit). The

forward-voltage drop is reduced to ILOAD x RDS(ON) of

P1. With a suitably chosen MOSFET, the voltage drop

can be reduced to millivolts.

In normal operating mode, internal GATE1 output

circuitry enhances P1. The constant enhancement ensures

P1 operates in a low RDS(ON) mode, but the gate-source

junction is not overstressed during high battery-voltage

applications or transients (many MOSFET devices specify

a Q20V VGS absolute maximum). As VCC drops below

10V, GATE1 is limited to GND, reducing P1 VGS to VCC.

In normal operation, the P1 power dissipation is very low:

P1 = ILOAD2 x RDS(ON)

During reverse-battery conditions, GATE1 is limited to

GND and the P1 gate-source junction is reverse biased.

P1 is turned off and neither the MAX16914/MAX16915

nor the load circuitry is exposed to the reverse-battery

voltage. Care should be taken to place P1 (and its inter-

nal drain-to-source diode) in the correct orientation for

proper reverse-battery operation.

Thermal Shutdown

The MAX16914/MAX16915 thermal-shutdown feature

turns off both MOSFETs if the IC junction temperature

exceeds the maximum allowable thermal dissipation.

When the junction temperature exceeds TJ = +170NC,

the thermal sensor signals the shutdown logic, turning off

both GATE1 and GATE2 outputs and allowing the device

to cool. The thermal sensor turns GATE1 and GATE2 on

again after the IC’s junction temperature cools by 20NC.

For continuous operation, do not exceed the absolute

maximum junction-temperature rating of TJ = +150NC.

Chip Information

PROCESS: BiCMOS

Package Information

For the latest package outline information and land patterns

(footprints), go to www.maximintegrated.com/packages. Note

that “+”, “#”, 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.

Ordering Information

+Denotes a lead(Pb)-free/RoHS-compliant package.

PACKAGE

TYPE

PACKAGE

CODE

OUTLINE

NO.

LAND

PATTERN NO.

10 μMAX U10+2 21-0061 90-0330

PART TEMP RANGE PIN-PACKAGE

MAX16914AUB+ -40NC to +125NC 10 FMAX

MAX16915AUB+ -40NC to +125NC 10 FMAX

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

www.maximintegrated.com Maxim Integrated

│

Revision History

REVISION

NUMBER

REVISION

DATE DESCRIPTION PAGES

CHANGED

0 9/09 Initial release —

1 4/13 Added commercial-grade OPNs to Ordering Information 1

2 10/14 Removed automotive reference from Applications and /V OPNs from

Ordering Information 1

3 2/15 Updated the Benefits and Features section 1

Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses

are implied. Maxim Integrated reserves the right to change the circuitry and specications without notice at any time. The parametric values (min and max limits)

shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.

MAX16914/MAX16915 Ideal Diode, Reverse-Battery, and Overvoltage

Protection Switch/Limiter Controllers

with External MOSFETs

│

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.