NSC LM2984T Datasheet

LM2984 Microprocessor Power Supply System

April 1998

General Description

The LM2984 positive voltage regulator features three independent and tracking outputs capable of delivering the power for logic circuits, peripheral sensors and standby memory in a typical microprocessor system. The LM2984 includes circuitry which monitors both itsownhigh-currentoutput and also an external µP. If any error conditions are sensed in either, a reset error flag is set and maintained until the malfunction terminates. Since these functions are included in the same package with the three regulators, a great saving in board space can berealizedinthetypicalmicroprocessor system. The LM2984 also features very low dropout voltages on each of its three regulator outputs (0.6V at the rated output current). Furthermore, the quiescent current can be reduced to 1 mA in the standby mode.

Designed also for vehicular applications, the LM2984 and all regulated circuitry are protected from reverse battery installations or 2-battery jumps. Familiar regulator features such as short circuit and thermal overload protection are also provided. Fixed outputsof5Vare available in the plastic TO-220 power package.

Typical Application Circuit

Features

n Three low dropout tracking regulators n Output current in excess of 500 mA n Fully specified for −40˚C to +125˚C operation n Low quiescent current standby regulator n Microprocessor malfunction RESET flag n Delayed RESET on power-up n Accurate pretrimmed 5V outputs n Reverse battery protection n Overvoltage protection n Reverse transient protection n Short circuit protection n Internal thermal overload protection n ON/OFF switch for high current outputs

+

n P

Product Enhancement tested

C

must be at least 10 µF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to

OUT

the regulator. This capacitor must be rated over the same operating temperature range as the regulator. The equivalent series resistance (ESR) of this capacitor is critical; see curve.

Order Number LM2984T

See NS Package Number TA11B

DS011252-1

Absolute Maximum Ratings (Note 2)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Input Voltage

Survival Voltage ( Operational Voltage 26V

<

100 ms) 60V

Operating Temperature Range (T Maximum Junction Temperature

(Note 3) 150˚C Storage Temperature Range −65˚C to +150˚C Lead Temperature

(Soldering, 10 sec.) 230˚C ESD Susceptability (Note 5) 2000V

) −40˚C to +125˚C

A

Internal Power Dissipation Internally Limited

Electrical Characteristics

=

V

14V, I

IN

temperature range, −40˚C ≤ T

(Pin 11)

V

OUT

Output Voltage 5 mA ≤ I

Line Regulation 9V ≤ VIN≤ 16V 2 25/25 mV

Load Regulation 5 mA ≤ I Output Impedance 250 mAdcand 10 mA

Quiescent Current I

Output Noise Voltage 10 Hz–100 kHz, I Long Term Stability 20 mV/1000 hr Ripple Rejection f Dropout Voltage I

Current Limit 0.92 0.75/0.60 A Maximum Operational Continuous DC 32 26/26 V Input Voltage Maximum Line Transient V Reverse Polarity V Input Voltage DC Reverse Polarity Input T ≤ 100 ms, R Voltage Transient

OUT

=

5 mA, C

=

10 µF, unless otherwise indicated. Boldface type refers to limits over the entire operating

OUT

≤ +125˚C, all other limits are for T

A

=

A

=

T

25˚C (Note 8) .

j

Parameter Conditions Typical Limit Units

(Note 4)

≤ 500 mA 5.00 4.85/4.75 V

O

6V ≤ VIN≤ 26V 5.15/5.25 V

7V ≤ VIN≤ 26V 5 50/50 mV

≤ 500 mA 12 50/50 mV

OUT

=

f

120 Hz

o

=

500 mA 38 100/100 mA

OUT

=

I

250 mA 14 50/50 mA

OUT

=

120 Hz 70 60/50 dB

o

=

500 mA 0.53 0.80/1.1 V

OUT

=

I

250 mA 0.28 0.50/0.70 V

OUT

≤ 6V, R

OUT OUT

OUT

≥ −0.6V, R

OUT

,24 mΩ

rms

=

100 mA 100 µV

OUT

=

100Ω,T≤100 ms 65 60/60 V

=

100Ω −30 −15/−15 V

OUT

=

100Ω −55 −35/−35 V

min

max

max max max

max max

min max max

min min

min

Electrical Characteristics

=

V

IN

perature range, −40˚C ≤ T

V

buffer

Output Voltage 5 mA ≤ I

Line Regulation 9V ≤ VIN≤ 16V 2 25/25 mV

Load Regulation 5 mA ≤ I Output Impedance 50 mAdcand 10 mA

Quiescent Current I

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14V, I

buf

=

5 mA, C

=

10 µF, unless otherwise indicated. Boldface type refers to limits over the entire operating tem-

buf

≤ +125˚C, all other limits are for T

A

=

A

=

T

25˚C (Note 8) .

j

Parameter Conditions Typical Limit Units

(Note 4)

(Pin 10)

≤ 100 mA 5.00 4.85/4.75 V

O

6V ≤ VIN≤ 26V 5.15/5.25 V

7V ≤ VIN≤ 26V 5 50/50 mV

≤ 100 mA 15 50/50 mV

buf

=

f

120 Hz

O

=

100 mA 8.0 15/15 mA

buf

, 200 mΩ

rms

min

max

max max max

max

Electrical Characteristics (Continued)

=

V

IN

perature range, −40˚C ≤ T

V

buffer

Output Noise Voltage 10 Hz–100 kHz, I Long Term Stability 20 mV/1000 hr Ripple Rejection f Dropout Voltage I Current Limit 0.23 0.15/0.15 A Maximum Operational Continuous DC 32 26/26 V Input Voltage Maximum Line V Transient T ≤ 100 ms Reverse Polarity V Input Voltage DC Reverse Polarity Input T ≤ 100 ms, R Voltage Transient

14V, I

buf

=

5 mA, C

=

10 µF, unless otherwise indicated. Boldface type refers to limits over the entire operating tem-

buf

≤ +125˚C, all other limits are for T

A

=

A

=

T

25˚C (Note 8) .

j

Parameter Conditions Typical Limit Units

(Note 4)

(Pin 10)

=

100 mA 100 µV

OUT

=

120 Hz 70 60/50 dB

o

=

100 mA 0.35 0.50/0.80 V

buf

≤ 6V, R

buf

≥ −0.6V, R

buf

=

100Ω, 65 60/60 V

buf

=

100Ω −30 −15/−15 V

buf

=

100Ω −55 −35/−35 V

buf

min

max

min min

min

Electrical Characteristics

=

V

14V, I

IN

perature range, −40˚C ≤ T

V

standby

Output Voltage 1 mA ≤ I

Line Regulation 9V ≤ VIN≤ 16V 2 25/25 mV

Load Regulation 0.5 mA ≤ I Output Impedance 5 mAdcand1mA Quiescent Current I

Output Noise Voltage 10 Hz–100 kHz, I Long Term Stability 20 mV/1000 hr Ripple Rejection f Dropout Voltage I

Current Limit 15 12/12 mA Maximum Operational 4.5V ≤ V Input Voltage R Maximum Line V Transient R Reverse Polarity V Input Voltage DC R Reverse Polarity Input T ≤ 100 ms, R Voltage Transient

stby

=

1 mA, C

=

10 µF, unless otherwise indicated. Boldface type refers to limits over the entire operating tem-

stby

≤ +125˚C, all other limits are for T

A

=

A

=

T

25˚C (Note 8) .

j

Parameter Conditions Typical Limit Units

(Note 4)

(Pin 9)

≤ 7.5 mA 5.00 4.85/4.75 V

O

6V ≤ VIN≤ 26V 5.15/5.25 V

7V ≤ VIN≤ 26V 5 50/50 mV

≤ 7.5 mA 6 50/50 mV

OUT

=

7.5 mA 1.2 2.0/4.0 mA

stby

=

I

2 mA 0.9 1.5/4.0 mA

stby

=

120 Hz 70 60/50 dB

o

=

1 mA 0.26 0.50/0.60 V

stby

=

I

7.5 mA 0.38 0.60/0.70 V

stby

≤ 6V, 65 60/60 V

stby

=

1000Ω

stby

≤ 6V, T ≤ 100 ms, 65 60/60 V

stby

=

1000Ω

stby

≥ −0.6V, −30 −15/−15 V

stby

=

1000Ω

stby

=

120 Hz 0.9 Ω

rms,fo

=

1 mA 100 µV

stby

=

1000Ω −55 −35/−35

min

max

max max max

max max

min max max

min

V

min

3 www.national.com

Electrical Characteristics

=

V

14V, C

IN

tire operating temperature range, −40˚C ≤ T

Parameter Conditions Typical Limit Units

Tracking and Isolation

Tracking I V

OUT–Vstby

Tracking I V

buf–Vstby

Tracking I V

OUT–Vbuf

Isolation (Note 1) R V

from V

buf

Isolation (Note 1) R V

from V

stby

Isolation (Note 1) R V

from V

OUT

Isolation (Note 1) R V

from V

stby

Note 1: Isolation refers to the ability of the specified output to remain within the tested limits when the other output is shorted to ground.

OUT

buf

OUT

=

10 µF, C

buf

=

10 µF, C

=

10 µF, unless otherwise indicated. Boldface type refers to limits over the en-

stby

≤ +125˚C, all other limits are for T

A

=

A

=

T

25˚C (Note 8) .

j

(Note 4)

≤ 500 mA, I

OUT

I

≤ 7.5 mA

stby

=

5 mA, I

OUT

I

≤ 7.5 mA

stby

≤ 500 mA, I

OUT

=

I

1mA

stby

=

1Ω,I

OUT

=

1Ω,I

OUT

=

1Ω,I

buf

=

1Ω,I

buf

=

5 mA,

buf

≤ 100 mA,

buf

≤ 100 mA,

buf

≤ 100 mA 5.00 4.50/4.50 V

buf

≤ 7.5 mA 5.00 4.50/4.50 V

stby

≤ 500 mA 5.00 4.50/4.50 V

OUT

≤ 7.5 mA 5.00 4.50/4.50 V

stby

±

30

±

30

±

30

±

100/±100 mV

±

100/±100 mV

±

100/±100 mV

5.50/5.50 V

max

min

max

min

max

min

max

min

max

Electrical Characteristics

=

V

14V, I

IN

Boldface type refers to limits over the entire operating temperature range, −40˚C ≤ T =

25˚C (Note 8)

Computer Monitor/Reset Functions

Low V

I

reset

V

Low V

reset

R

t voltage

Power On Reset VµP Delay (T ∆V

Low (Note 6) −350 −225/−175 mV

OUT

Reset Threshold −500/−550 mV ∆V

High (Note 6) 600 225/175 mV

OUT

Reset Threshold 750/800 mV Reset Output VµP Leakage µP

Input Current (Pin 4) VµP

mon

µP

Input 1.22 0.80/0.80 V

mon

Threshold Voltage 1.22 2.00/2.00 V µP Monitor Reset VµP Oscillator Period (T µP Monitor Reset VµP Oscillator Pulse Width (RESET Minimum µP Monitor (Note 7) 2 µs Input Pulse Width Reset Fall Time R

OUT

=

5 mA, I

=

5 mA, I

buf

stby

=

5 mA, R

=

130 kΩ,C

t

=

0.33 µF, C

t

=

0.47 µF, unless otherwise indicated,

mon

≤ +125˚C, all other limits are for T

A

Parameter Conditions Typical Limit Units

(Note 4)

=

IN

=

IN

4V, V 4V, I

=

0.4V 5 2/0.50 mA

rst

=

1 mA 0.10 0.40/0.40 V

rst

(Pin 2) 1.22 1.15/0.75 V

1.22 1.30/2.00 V

=

5V 50 45/17.0 ms

mon

VµP

rst

dly

mon

mon mon

mon

window

mon

=

10k, V

) 50 55/80.0 ms

1.2 R

tCt

=

= =

=

pw

=

5V, V

12V 0.01 1/5.0 µA

rst

2.4V 7.5 25/25 µA

0.4V 0.01 10/15 µA

0V 50 45/30 ms

0.82 R

) 50 55/70 ms

tCmon

0V 1.0 0.7/0.4 ms

=

2000 C

rst

) 1.0 1.3/2.10 ms

mon

=

≤ 10 pF 0.20 1.00/1.00 µs

5V, C

rst

max

min

max

max max

max

=

T

J

min

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Electrical Characteristics (Continued)

=

V

14V, I

IN

Boldface type refers to limits over the entire operating temperature range, −40˚C ≤ T =

25˚C (Note 8)

Computer Monitor/Reset Functions

Reset Rise Time R On/Off Switch Input V Current (Pin 8) V On/Off Switch Input 1.22 0.80/0.80 V Threshold Voltage 1.22 2.00/2.00 V

Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating the device beyond its specified operating ratings.

Note 3: Thermal resistance without a heatsink for junction-to-case temperature is 3˚C/W. Thermal resistance case-to-ambient is 40˚C/W. Note 4: Tested Limits are guaranteed and 100%production tested. Note 5: Human body model, 100 pF capacitor discharged through a 1500Ω resistor. Note 6: Internal comparators detect when the main regulator output (V

High or ∆V

∆V

OUT

to go high again after a delay set by R Note 7: This parameter is a measure of how short a pulse can be detected at the µP Monitor Input. This parameter is primarily influenced by the value of C

Application Hints Section.) Note 8: To ensure constant junction temperature, low duty cycle pulse testing is used.

OUT

=

5 mA, I

=

5 mA, I

buf

stby

=

5 mA, R

=

130 kΩ,C

t

=

0.33 µF, C

t

=

0.47 µF, unless otherwise indicated,

mon

≤ +125˚C, all other limits are for T

A

Parameter Conditions Typical Limit Units

(Note 4)

=

rst

=

ON

=

ON

Low, and set the Reset Error Flag low. The Reset Error Flag is held low until V

OUT

and Ct. (see application section).

t

10k, V

=

rst

≤ 10 pF 0.60 1.00/1.50 µs

5V, C

rst

2.4V 7.5 25/25 µA

0.4V 0.01 10/10 µA

) changes from the measured output voltage (with V

OUT

returns to regulation. The Reset Error Flag is then allowed

OUT

=

14V) by the specified amount,

IN

mon

Block Diagram

=

max max max

min

max

. (See

T

J

DS011252-2

5 www.national.com