Rainbow Electronics MAX16024 User Manual

General Description

The MAX16023/MAX16024 low-power battery-backup cir­cuits with a regulated output are capable of delivering up
to 100mA output current. The MAX16023/MAX16024
include a low-dropout regulator, a microprocessor (µP)
reset circuit, and a battery switchover circuit. Additional
available features include a manual reset, a power-fail
comparator, and a battery-on indicator. These devices
reduce the number of external components to minimize
board space and improve reliability.

The MAX16023/MAX16024 are ideally suited for provid­ing power for backing up critical memory such as static
random-access memory (SRAM) or real-time clocks
(RTCs). The regulated output is powered by V

CC

when it
is present and switches over to the backup power dur­ing brownout. The MAX16023/MAX16024 accept an
input voltage from 1.53V to 5.5V and provide fixed stan­dard output voltages of 1.2V, 1.8V, 2.5V, 3.0V, and 3.3V.
The MAX16024 offers the ability to externally set the out­put voltage using a resistive divider. All outputs are
available with push-pull or open-drain configurations.

The MAX16023 offers a power-fail comparator for monitor­ing an additional voltage or for providing an early power­fail warning. Another feature includes a manual-reset input
(MAX16023/MAX16024). The MAX16024 also features
a battery-on indicator and chip-enable gating function.

The MAX16023/MAX16024 are offered in 8- and 10-pin
TDFN packages and are fully specified from -40°C to
+85°C temperature range.

Applications

Main/Backup Power for RTCs/SRAM
Industrial Controls
GPS Systems
Set-Top Boxes
Point-of-Sale Equipment
Portable/Battery Equipment

Features

o System Monitoring for 5V, 3.3V, 3V, 2.5V, or 1.8V

Power-Supply Voltages

o 100mA Low-Dropout Regulator

o Factory-Trimmed and Adjustable Output Voltages

o 1.53V to 5.5V Operating Voltage Range

o Low-Power Consumption: 4µA (typ)

o Power-Fail Comparators for Monitoring Voltages

Down to 0.6V

o Battery-On Indicator

o Battery Freshness Seal

o On-Board Gating of CE Signals, 1.5ns

Propagation Delay (MAX16024)

o Debounced Manual-Reset Input

o 145ms (min) Reset Timeout Period

o Tiny 8-Pin and 10-Pin TDFN Packages

o UL

®

Certified to Conform to IEC60950-1

MAX16023/MAX16024

Battery-Backup Circuits with

Regulated Output Voltage

________________________________________________________________

Maxim Integrated Products

1

19-4249; Rev 0; 8/08

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.

Ordering Information

PART

PIN-PACKAGE

MAX16023_TA_ _ _+T

8 TDFN-EP*

MAX16024_TB_ _ _+T

10 TDFN-EP*

The first placeholder “_” designates reset output options. A letter
“L” in this placeholder indicates a push-pull output and letter “P”
indicates an open-drain output. The next placeholder “_” desig­nates the reset threshold (Table 1). The last two placeholders
“_ _” designate output voltage (Table 2). For the MAX16024 with
adjustable output voltage version, there are no last two place­holders.

+

Denotes a lead-free/RoHS-compliant package.

T = Tape and reel.

*

EP = Exposed pad.

Pin Configurations

UL is a registered trademark of Underwriters Laboratories, Inc.

TEMP RANGE

-40°C to +85°C

-40°C to +85°C

OUT

8 7 6 5

MAX16023

+

1 2 3 4

CC

V

BATT

TDFN

*EP *EP

PFI

MR

*EP = EXPOSED PAD

OUT

MAX16024

CC

V

TDFN

RESET

BATT

CEOUT

10 9 8 7

+

1 2 3 4

CEIN

PFO

GND

RESET

GND

BATT ONSET

6

5

MR

MAX16023/MAX16024

Battery-Backup Circuits with
Regulated Output Voltage

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= 1.53V to 5.5V, V

BATT

= 3V, reset not asserted, TA= TJ= -40°C to +85°C, C

OUT

= 10µF, unless otherwise noted. Typical val-

ues are at T

A

= TJ= +25°C.) (Note 2)

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.

VCC, BATT, OUT to GND..........................................-0.3V to +6V

RESET, PFO, BATT ON (all open drain)

to GND..................................................................-0.3V to +6V

RESET, PFO, BATT ON (all push-pull)

to GND .................................................-0.3V to (V

OUT

+ 0.3V)

PFI, CEIN, CEOUT to GND.......................-0.3V to (V

OUT

+ 0.3V)

MR to GND .................................................-0.3V to (V

CC

+ 0.3V)
Input Current
V

CC

Peak Current.....................................................................1A

V

CC

Continuous Current ...............................................250mA

BATT Peak Current .......................................................500mA

BATT Continuous Current ...............................................70mA

Output Current

OUT Short Circuit to GND Duration ....................................10s

RESET, BATT ON, CEOUT..............................................20mA

Continuous Power Dissipation (T

A

= +70°C)

8-Pin TDFN (derate 24.4mW/°C above +70°C) .........1951mW

10-Pin TDFN (derate 24.4mW/°C above +70°C) .......1951mW

Thermal Resistance (Note 1)

θ

JA

(8-Pin and 10-Pin TDFN)........................................41°C/W

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

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

,

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.maxim-ic.com/thermal-tutorial

.

Operating Voltage Range V

Supply Current I

Supply Current in Battery-Backup
Mode

BATT Standby Current VCC > V

SET Reference Voltage V

SET Input Leakage Current MAX16024_TB_, SET = 1.2V -20 +20 nA

Output Voltage Range V

Output Voltage Accuracy I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

V

CC

BATT

CC

I

BATT

SET

OUT

(Note 3) 1.53 5.5 V

VCC = LDO + 0.5V,
no load

VCC = LDO + 0.5V,
I

= 20mA

OUT

VCC = 0, V
no dropout, no load

BATT

MAX16024_TB_, VCC = 2.2V 1.144 1.2 1.272 V

MAX16024_TB_, VCC > V

= 1mA

OUT

LDO = 1.2V 4.3 6

LDO = 1.8V 4.7 7

LDO = 2.5V 5.2 7.5

LDO = 3V 5.5 8

LDO = 3.3V 5.7 8

LDO = 1.2V 16 20

LDO = 1.8V 16 21

LDO = 2.5V 16 18.1

LDO = 3V 17 18.6

LDO = 3.3V 17 19

= 3V,

BATT

+ 0.2V -0.01 +0.01 µA

OUT

LDO = 1.2V 1.145 1.2 1.270

LDO = 1.8V 1.704 1.8 1.900

LDO = 2.5V 2.368 2.5 2.634

LDO = 3V 2.837 3 3.165

LDO = 3.3V 3.114 3.3 3.482

3.5 5.26 µA

1.8 5.25 V

µA

V

MAX16023/MAX16024

Battery-Backup Circuits with

Regulated Output Voltage

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC= 1.53V to 5.5V, V

BATT

= 3V, reset not asserted, TA= TJ= -40°C to +85°C, C

OUT

= 10µF, unless otherwise noted. Typical val-

ues are at T

A

= TJ= +25°C.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Line Regulation

Load Regulation VCC = V

Dropout Voltage

Output Current Limit

Battery Freshness Leakage
Current

RESET OUTPUT (RESET)

Reset Threshold V

VCC Falling to Reset Delay t

Reset Timeout Period t

RESET Output High Voltage
(Push-Pull Output)

RESET Output Leakage Current
(Open-Drain Output)

POWER-FAIL COMPARATOR (PFI, PFO)

PFI Input Threshold V

PFI Input Hysteresis V

PFI Input Current I

PFO Output Low Voltage

PFO Output High Voltage

(Push-Pull Output)
PFO Leakage Current

(Open-Drain Output)
PFO Delay Time (V

MANUAL RESET (MR)

Input Low Voltage V

Input High Voltage V

Pullup Resistance Pullup resistance to V

Glitch Immunity 100 ns
MR to Reset Delay 120 ns

V
I

OUT

I

OUT

CC

= (V

= 1mA

= 50mA

OUT

OUT

+ 1V, I

+ 1V) to (V

OUT

(Note 4)

VCC = 1.6V 75

V

≥ 2V 150

CC

= 5.5V 10 nA

V

BATT

TH

VCC falling at 10V/ms 20 µs

RD

VCC rising 145 215 285 ms

RP

V

OL

V

OH

PFT

PFI-HYS

PFI

IL

IH

= 3.3V, I

OUT

V

= 1.8V, I

OUT

V

= 1.2V, I

OUT

VCC ≥ 1.1 x VTH, I
RESET deasserted

= 5.5V, reset deasserted 1 µA

V

RESET

V

falling, 1.6V ≤ VCC ≤ 5.5V 0.570 0.590 0.611 V

PFI

V

= 1.8V, I

OUT

=1.2V, I

V

OUT

I

V

= 100µA, PFO deasserted V

SOURCE

= 5.5V, PFO deasserted 1 µA

PFO

+ 100mV) to (V

PFI

= 3.2mA, RESET asserted 0.3

SINK

= 1mA, RESET asserted 0.3RESET Output Low Voltage V

SINK

= 100µA, RESET asserted 0.3

SINK

SOURCE

= 1mA, PFO asserted 0.3

SINK

= 100µA, PFO asserted 0.3

SINK

PFI

CC

+ 2V),

OUT

0.2 1.0 %/V

= 1mA to 2mA 0.15 1.0 %

LDO = 1.2V 500

LDO = 1.8V 200

LDO = 2.5V 180

LDO = 3V 150

LDO = 3.3V 150

(See Table 1) V

= 100µA,

V

- 0.3V V

OUT

30 mV

-1 +1 µA

- 0.3V V

OUT

- 100mV) 20 µs

0.3 x V

CC

0.7 x V

CC

20 30 kΩ

mV

mA

V

V

V

MAX16023/MAX16024

Battery-Backup Circuits with
Regulated Output Voltage

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VCC= 1.53V to 5.5V, V

BATT

= 3V, reset not asserted, TA= TJ= -40°C to +85°C, C

OUT

= 10µF, unless otherwise noted. Typical val-

ues are at T

A

= TJ= +25°C.) (Note 2)

Note 2: All devices are 100% production tested at TA= +25°C and TA= +85°C. Limits over temperature are guaranteed by design.
Note 3: V

BATT

can be 0 anytime or VCCcan go down to 0 if V

BATT

is active (except at startup).

Note 4: Dropout voltage is defined as (V

IN

- V

OUT

) when V

OUT

is 2% below the value of V

OUT

when VIN= V

OUT

+ 1V.

Note 5: CEIN to CEOUT resistance is tested with VCC= 5V and V

CEIN

= 0 or 5V.

Note 6: Use external current-limiting resistor to limit current to 20mA (max).

BATTERY-ON INDICATOR (BATT ON)

Output Low Voltage V

Output High Voltage
(Push-Pull Output)

Output Leakage Current
(Open-Drain Output)

Output Short-Circuit Current

CE GATING (CEIN, CEOUT)

CEIN Leakage Current Reset asserted, VCC = 0.9 x VTH or 0 -1 +1 µA
CEIN to CEOUT Resistance VCC = 5V, reset deasserted 8 50 Ω
CEOUT Short-Circuit Current Reset asserted, CEOUT = 0 0.75 2 mA

CEIN to CEOUT Propagation

Delay

Output High Voltage V
Reset to CEOUT Delay 12 µs

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

V

= 1.2V, I

OUT

deasserted

V

= 1.8V, I

OL

V

OH

OH

OUT

deasserted

V

= 3.3V, I

OUT

deasserted

I

V

Sink current, V
(Note 6)

50Ω source, C

I

= 100µA, BATT ON asserted V

SOURCE

= 5.5V 1 µA

CC

= 100µA, reset asserted V

SOURCE

= 100µA, BATT ON

SINK

= 1mA, BATT ON

SINK

= 3.2mA, BATT ON

SINK

= 5V

CC

= 50pF, VCC = 4.75V 1.5 7 ns

LOAD

- 0.3V V

OUT

60 mA

- 0.3V V

OUT

0.3

0.3

0.3

V

MAX16023/MAX16024

Battery-Backup Circuits with

Regulated Output Voltage

_______________________________________________________________________________________ 5

Typical Operating Characteristics

(V

CC

= 5V, V

BATT

= 0, I

OUT

= 0, TA= +25°C, unless otherwise noted.)

Table 1. Reset Threshold Ranges Table 2. Fixed Output Voltage

SUFFIX

RESET THRESHOLD RANGES (V)

MIN TYP MAX

L 4.508 4.63 4.906

M 4.264 4.38 4.635

T 2.991 3.08 3.239

S 2.845 2.93 3.080

R 2.549 2.63 2.755

Z 2.243 2.32 2.425

Y 2.117 2.19 2.288

W 1.603 1.67 1.733

V 1.514 1.575 1.639

SUFFIX

33 3.3

30 3.0

25 2.5

18 1.8

12 1.2

NOMINAL OUTPUT

VOLTAGE (V)

25

20

15

10

SUPPLY CURRENT (μA)

CC

V

5

0

1.5 5.5

VCC SUPPLY CURRENT

SUPPLY VOLTAGE

vs. V

CC

MAX16024PTBS25+

3.02.5 4.52.0 3.5 5.04.0

VCC SUPPLY VOLTAGE (V)

VCC SUPPLY CURRENT

vs. TEMPERATURE

10

V
V

OUT

= 2.93V

TH

= 2.5V

MAX16023 toc01

9

8

7

6

5

4

SUPPLY CURRENT (μA)

3

CC

V

2

1

0

-40 85

TEMPERATURE (°C)

MAX16024PTBS25+

V
V

OUT

= 2.93V

TH

6010 35-15

= 2.5V

MAX16023 toc02

BATT SUPPLY CURRENT

SUPPLY VOLTAGE

vs. V

6

5

4

3

2

BATT SUPPLY CURRENT (μA)

1

0

0 3.5

CC

V

V

1.0 3.00.5 2.52.01.5

VCC SUPPLY VOLTAGE (V)

MAX16024PTBS25+

= 3.0V

BATT

= 2.8V

BATT

V
V

OUT

= 2.93V

TH

= 2.5V

MAX16023 toc03

BATTERY SUPPLY CURRENT

vs. TEMPERATURE

5

4

3

2

1

BATTERY SUPPLY CURRENT (μA)

0

-40 85

TEMPERATURE (°C)

MAX16024PTBS25+

V

BATT

= +3.0V

V

CC

6010 35-15

= 0

10

8

MAX16023 toc04

6

4

2

0

-2

-4

BATT STANDBY CURRENT (nA)

-6

-8

-10

-40 85

BATT STANDBY CURRENT

vs. TEMPERATURE

VCC = 3.3V

V

BATT

TEMPERATURE (°C)

= 3.0V

6010 35-15

1.0

MAX16023 toc05

0.8

0.6

0.4

OUTPUT VOLTAGE LOW (V)

0.2

0

02014610218

RESET OUTPUT VOLTAGE LOW

vs. SINK CURRENT

MAX16024PTBS25+

MAX16023 toc06

168124

SINK CURRENT (mA)

MAX16023/MAX16024

Battery-Backup Circuits with
Regulated Output Voltage

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(V

CC

= 5V, V

BATT

= 0, I

OUT

= 0, TA= +25°C, unless otherwise noted.)

VCC FALLING TO RESET DELAY

vs. TEMPERATURE

MAX16023 toc07

TEMPERATURE (°C)

DELAY (μs)

6010 35-15

20

40

60

80

100

10

30

50

70

90

0

-40 85

VCC FALLING 10V/ms

RESET TIMEOUT PERIOD

vs. TEMPERATURE

MAX16023 toc08

TEMPERATURE (°C)

RESET TIMEOUT PERIOD (ms)

6035-15 10

185

190

195

200

210

205

215

220

180

-40 85

NORMALIZED RESET THRESHOLD

vs. TEMPERATURE

MAX16023 toc09

TEMPERATURE (°C)

NORMALIZED RESET THRESHOLD

6010 35-15

0.990

1.005

1.015

1.020

0.985

0.995

1.000

1.010

0.980

-40 85

MAX16024PTBS25+

V

OUT

= 2.5V

MAXIMUM TRANSIENT DURATION

vs. RESET THRESHOLD OVERDRIVE

RESET THRESHOLD OVERDRIVE (mV)

TRANSIENT DURATION (ms)

MAX16023 toc10

0 200 400 600 800 1000

0

25

50

75

100

125

150

175

200

RESET OCCURS ABOVE THE CURVE

DROPOUT VOLTAGE

vs. LOAD CURRENT

MAX16023 toc11

LOAD CURRENT (mA)

DROPOUT VOLTAGE (mV)

8040 6020

150

350

450

500

100

300

50

200

250

400

0

01007030 5010 90

MAX16024PTBS25+

OUTPUT VOLTAGE

vs. LOAD CURRENT

MAX16023 toc12

LOAD CURRENT (mA)

OUTPUT VOLTAGE (V)

8040 6020

2.42

2.58

2.66

2.70

2.38

2.54

2.34

2.46

2.50

2.62

2.30
01007030 5010 90

MAX16024PTBS25+

V

OUT

= 2.5V

TA = -40°C

TA = +25°C

TA = +85°C