Maxim Integrated MAX17020 Datasheet

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or visit Maxim’s website at www.maxim-ic.com.

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

19-4118; Rev 2; 2/09

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General Description

The MAX17020 is a dual Quick-PWM™ step-down
power-supply (SMPS) controller with synchronous rec­tification, intended for main 5V/3.3V or I/O 1.5V/1.05V
power generation in battery-powered systems. Low­side MOSFET sensing provides a simple low-cost,
highly efficient current sense for valley current-limit
protection. Combined with the output overvoltage and
undervoltage protection features, this current limit
ensures robust output supplies.

The 5V/3.3V or 1.5V/1.05V SMPS outputs can save
power by operating in pulse-skipping mode or in ultra­sonic mode to avoid audible noise. Ultrasonic mode
forces the controller to maintain switching frequencies
greater than 20kHz at light loads.

An internal 100mA linear regulator can be used to
either generate the 5V bias needed for power-up or
other lower power “always-on” suspend supplies. An
independent bypass input allows automatic bypassing
of the linear regulator when the SMPS is active.

This main controller also includes a secondary feed­back input that triggers an ultrasonic pulse (DL1 turned
on) if the SECFB voltage drops below its threshold volt­age. This refreshes an external charge pump driven by
DL1 without overcharging the output voltage.

The device includes independent shutdown controls to
simplify power-up and power-down sequencing. To
prevent current surges at startup, the internal voltage
target is slowly ramped up from zero to the final target
over a 1ms period. To prevent the output from ringing
below ground in shutdown, the internal voltage target
is ramped down from its previous value to zero over a
1ms period. Two independent power-good outputs
simplify the interface with external controllers.

The MAX17020 is a pin-for-pin replacement of the
MAX8778.

Features

Applications

+

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

*

EP = Exposed pad.

Dual Quick-PWM
Internal 100mA 5V or Adjustable Linear Regulator
Independent LDO Bypass Input
Internal Boost Diodes
Secondary Feedback Input Maintains Charge Pump

3.3V 5mA RTC Power (Always On)
OUT1: 5V or 1.5V Fixed or 0.7V Adjustable

Feedback
OUT2: 3.3V or 1.05V Fixed or Dynamic Adjustable
Dynamic 0V to 2V REFIN2 Input on Second SMPS
2V ±1% 50µA Reference
6V to 24V Input Range (28V max)
Ultrasonic Mode
Independent SMPS and LDO Enable Controls
Independent SMPS Power-Good Outputs
Minimal Component Count

Notebook Computers

Main System Supply (5V and 3.3V Supplies)

I/O System Supply (1.5V and 1.05V Supplies)

Graphic Cards

DDR1, DDR2, DDR3 Power Supplies

Game Consoles

Low-Power I/O and Chipset Supplies

Two-to-Four Li+ Cell Battery-Powered Devices

PDAs and Mobile Communicators

Telecommunication

MAX17020

THIN QFN (T3255-4)

5mm x 5mm

TOP VIEW

A "+" SIGN FIRST-PIN INDICATOR DENOTES A LEAD-FREE PACKAGE.

29

30

28

27

12

11

13

TON

ONLDO

RTC

IN

LDO

14

REF

DL2

AGND

SECFB

BST2

V

DD

DL1

12

PGOOD2

4567

2324 22 20 19 18

SKIP

OUT2

ON1

PGOOD1

ILIM1

FB1

V

CC

PGND

3

21

31

10

ILIM2

OUT1

32

9

REFIN2

+

BYP

ON2

26

15

DH1

DH2

25

16

LX1

LDOREFIN

BST1

8

17

LX2

Pin Configuration

Quick-PWM is a trademark of Maxim Integrated Products, Inc.

EVALUATION KIT

AVAILABLE

PART TEMP RANGE PIN-PACKAGE

M AX 17020E TJ+ -40°C to +85°C 32 TQFN

MAX17020

Dual Quick-PWM Step-Down Controller
with Low-Power LDO, RTC Regulator

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

(Note 3)

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.

IN, ONLDO to GND ................................................-0.3V to +28V

V

DD

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

RTC, LDO to GND ....................................................-0.3V to +6V

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

ON1, ON2 to GND....................................................-0.3V to +6V

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

CC

+ 0.3V)

REF, ILIM_, TON, SKIP to GND..................-0.3V to (V

CC

+ 0.3V)

FB1, REFIN2, LDOREFIN to GND ............................-0.3V to +6V

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

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

LDO

+ 0.3V)

GND to PGND .......................................................-0.3V to +0.3V

DL_ to PGND..............................................-0.3V to (V

DD

+ 0.3V)

BST_ to GND ..........................................................-0.3V to +34V

BST_ to V

DD

............................................................-0.3V to +28V

DH1 to LX1 ..............................................-0.3V to (V

BST1

+ 0.3V)

BST1 to LX1..............................................................-0.3V to +6V

DH2 to LX2 ..............................................-0.3V to (V

BST2

+ 0.3V)

BST2 to LX2..............................................................-0.3V to +6V

LDO, RTC, REF Short Circuit to GND.........................Momentary

RTC Current Continuous.....................................................+5mA

LDO Current (Internal Regulator)

Continuous..................................................................+100mA

LDO Current (Switched Over) Continuous .....................+200mA

Continuous Power Dissipation (T

A

= +70°C)
32-Pin 5mm x 5mm TQFN

(derate 34.5mW/°C above +70°C).................................2.76W

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

Dual Mode is a trademark of Maxim Integrated Products, Inc.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

INPUT SUPPLIES

IN Standby Supply Current I

IN Shutdown Supply Current I

IN Supply Current I

VCC Supply C urrent I

PWM CONTROLLERS

OUT1 Output Voltage Accuracy
(Note 1)

OUT1 Voltage Adjust Range 0.7 5.5 V

FB1 Dual-Mode™ Threshold
Voltage Leve ls

FB1 Input B ia s Current I

IN(STBY)

IN(SHDN)

IN

CC

V

OUT1

V

FB1

FB1

VIN = 6V to 24V, ON1 = ON2 = GND,
ONLDO = V

VIN = 4.5V to 24V,
ON1 = ON2 = ONLDO = GND

ON1 = ON2 = REFIN2 = VCC,
SKIP = FB1 = GND,
V

OUT2

ON1 = ON2 = REFIN2 = VCC,
SKIP = FB1 = GND,
V

OUT2

5V preset output: FB1 = GND,

= 12V, SKIP = V

V

IN

1.5V preset output: FB1 = VCC (5V),

= 12V, SKIP = V

V

IN

Adju stable feedback output,

= 12V, SKIP = V

V

IN

Low 0.04 0.110

High

V

FB1

CC

= 3.5V, V

= 3.5V, V

= 0.8V, TA = +25°C -0.2 +0.2 µA

OUT1

OUT1

= 5.3V

= 5.3V

CC

CC

CC

85 175 µA

50 70 µA

0.1 0.2 mA

1.0 1.5 mA

4.95 5.00 5.05

1.485 1.50 1.515

0.693 0.700 0.707

V

-

CC

1.6V

VCC -

0.7V

V

V

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

(Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

3.3V preset output: REFIN2 = VCC (5V),
V

= 12V, SKIP = V

OUT2 Output Voltage Accuracy
(Note 1)

V

OUT2

IN

1.05V preset output: REFIN2 = RTC (3.3V),
V

= 12V, SKIP = V

IN

Tracking output: V

= 12V, SKIP = V

V

IN

CC

CC

REFIN2

CC

= 1.0V,

OUT2 Voltage-Adjust Range 0 2 V

REFIN2 Voltage-Adjust Range 0 2 V

V

= 2.2V, TA = +25°C -0.1 +0.1

REFIN2 Input Bias Current I

REFIN2 Dual-Mode Threshold
Voltage Leve ls

Load Regulation Error

REFIN2

REFIN2

V

= 0, TA = +25°C -0.5 +0.1

REFIN2

Low (REFIN2 = RTC) 2.2 3.0

High (REFIN2 = V

Either SMPS, SKIP = VCC, I
Either SMPS, SKIP = REF, I
Either SMPS, SKIP = GND, I

CC

)

= 0 to 5A -0.1

LOAD

= 0 to 5A -1.7

LOAD

= 0 to 5A -1.5

LOAD

Line Regulation Error Either SMPS, VIN = 6V to 24V 0.005 %/V

TON = GND or REF
(400kHz)

TON = V

(200kHz) 1895 2105 2315

CC

TON = GND (500kH z) 475 555 635

TON = REF or V

CC

(300kHz)

DH1 On-Time t

DH2 On-Time t

Minimum Off-Time t

OFF(MIN)

Soft-Start/Stop Slew Rate t

Soft-Start/Stop Slew Rate t

Dynamic REFIN2 Slew Rate t

Ultrasonic Operating Frequency f

SW(USONIC)

SECFB Threshold Voltage V

SECFB Input Bias Current I

VIN = 12V,

ON1

V

OUT1

(Note 2)

VIN = 12V,
V

ON2

OUT2

(Note 2)

(Note 2) 250 400 ns

SS

SS

DYN

Risi ng/falling edge on ON1 or ON2 (preset)

Risi ng/falling edge on ON2 (REFIN2 AD J)

Risi ng edge on REFIN2 8 mV/µs
SKIP = open (REF) 20 27 kHz

SECFB

SECFB VSECFB

1.94 2.0 2.06 V

= 5.0V

= 3.3V

= 2.2V, TA = +25°C -0.2 +0.2 µA

LINEAR REGULATOR (LDO)

VIN = 24V, LDOREFIN = BYP = GND,

< 100mA

LDO

< 100mA

LDO

= 0.5V,

LDO

= 2 x V

< 100mA

LDOR EFI N

LDOR EFI N

0.3 2.0 V

= 0 or 2V, TA = +25°C -0.5 +0.5 µA

LDO Output-Voltage Accuracy V

LDOREFIN Input Range V

LDOREFIN Leakage Current I

LDOREFIN VLDO

LDOR EFI N VLDOREFIN

LDOREFIN Dual-Mode
Threshold Voltage

LDO

0mA < I
VIN = 24V, LDOREFIN = VCC, BYP = GND,

0mA < I
VIN = 24V, BYP = GND, V
0mA < I

LDOREFIN low threshold 0.1 0.15 0.20

LDOREFIN high threshold

3.267 3.30 3.333

1.040 1.050 1.060

V

0.995 1.00 1.005

µA

V

CC

1.0V

-

V

CC

0.4V

V

-

%

895 1052 1209

833 925 1017

1

ms

ns

ns

1 mV/µs

4.90 5.0 5.10

3.23 3.3 3.37

V

0.960 1.0 1.040

V

-

CC

2V

VCC -

1.5V

VCC -

0.9V

V

MAX17020

Dual Quick-PWM Step-Down Controller
with Low-Power LDO, RTC Regulator

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

(Note 3)

)

)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

LDO Short-Circuit Current I

LDO Regulation Reduction/
Bypass Switchover Threshold

LDO Bypass Switchover
Threshold

LDO Bypass Switchover
Startup Timeout

LDO Bypass Switch Resistance LDO to BYP, V

VCC Undervoltage-Lockout
(UVLO) Threshold

Thermal-Shutdown Threshold T

3.3V ALWAYS-ON LINEAR REGULATOR (RTC)

RTC Output-Voltage Accuracy V

RTC Short-Circuit Current I

REFERENCE (REF)

Reference Voltage V

Reference Load-Regulation Error ΔV

REF Lockout Voltage V

OUT1 FAULT DETECTION

OUT1 Overvoltage Trip
Threshold

OU T1 Over voltag e Faul t­P r op ag ati on D el ay

OUT1 Undervoltage-Protection
Trip Threshold

OUT1 Output-Undervoltage
Fault-Propagation Delay

PGOOD1 Lower Trip Threshold

PGOOD1 Propagation Delay t

PGOOD1 Output Low Voltage

PGOOD1 Leakage Current I

ILIM(LDO

t

BYP

V

U V L O( V C C )

SHDN

RTC

ILIM(RTC

REF

R E F ( U V L O)

V

OV P ( OU T 1)

t

OVP

V

U V P ( OU T 1)

t

UVP

PGOOD1

PGOOD1

LDO = GND 100 260 mA

With respect to the LDO voltage,
falling edge of BYP

With respect to the LDO voltage,
rising edge of BYP

Rising edge of BYP to bypass gate pulled low 500 μs

= 5V (Note 4) 1.2 4.5 Ω

BYP

Falling edge of VCC,
PWM disabled below this threshold

Rising edge of V

Hysteresis = 10°C +160 °C

ON1 = ON2 = GND, VIN = 6V to 24V,
0 < I

ON1 = ON2 = ONLDO = GND,
V

RTC = GND 5 30 mA

VCC = 4.5V to 5.5V, I

REFIREF

Rising edge, 350mV (typ) hysteresis 1.95 V

With respect to error-comparator threshold 13 16 19 %

FB1 forced 50mV above trip threshold 10 μs

With respect to error-comparator threshold 65 70 75 %

With respect to error-comparator threshold,
falling edge, hysteresis = 1%

FB1 forced 50mV beyond PGOOD1 trip
threshold, falling edge

V
I

V
PGOOD1 forced to 5.5V, T

< 5mA

RTC

= 6V to 24V, 0 < I

IN

= -20μA to 50μA -10 +10 mV

= 0.56V (PGOOD1 low impedance),

FB1

= 4mA

SINK

= 0.70V (PGOOD1 high impedance),

FB1

CC

< 5mA

RTC

= 0 1.980 2.00 2.020 V

REF

= +25°C

A

-11.0 -8.5 -6.0 %

-6.5 %

3.8 4.0 4.3

4.2

3.23 3.33 3.43

3.19 3.47

10 μs

-19 -16 -13 %

10 μs

0.3 V

1μA

V

V

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

(Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUT2 FAULT DETECTION

OUT2 Overvoltage Tr ip
Threshold

OUT2 Overvoltage
Fault-Propagation Delay

OUT2 Undervoltage-Protection
Trip Threshold

OUT2 Overvoltage
Fault-Propagation Delay

OUT2 Output Undervoltage
Fault-Propagation Delay

Dynamic REFIN2 Transition
PGOOD Blanking Threshold

PGOOD2 Lower Trip Threshold

PGOOD2 Propagation Delay t

PGOOD2 Output-Low Voltage

PGOOD2 Leakage Current I

CURRENT LIMIT

ILIM_ Adjustment Range V

ILIM_ Current I

Valley Current-Limit Threshold
(Adjustable)

Current-Limit Threshold
(Negative)

Ultrasonic Current-Limit Threshold V

Current-Limit Threshold
(Zero Crossing)

V

OVP(OUT2)

t

OVP

V

UVP(OUT2)

t

OVP

t

UVP

PGOOD2

PGOOD2

ILIM

5 µA

ILIM

V

VALLEY VAGND

V

NEG

NEG(US)

V

ZX

Preset mode (REFIN2 = RTC or VCC): with
respect to error-comparator threshold

Dynamic transition,
SKIP = REF or V

Tracking mode: with respect to REFIN2 voltage 170 200 230 mV

Minimum overvoltage threshold 0.7 V

OUT2 forced 50mV above trip threshold 10 µs

Preset mode: with respect to
error-comparator threshold

Tracking mode: with respect to REFIN2 voltage -250 -300 -350 mV

OUT2 forced 50mV above trip threshold 10 µs

OUT2 forced 50mV below trip threshold 10 µs

Blanking initiated; REFIN2 deviation from the
internal target voltage (error-comparator
threshold); hysteresis = 5mV

Preset mode: with respect to error-comparator
threshold, falling edge, hysteresis = 1%

Tracking mode: with respect to REFIN2
voltage, falling edge, hysteresis = 12mV

OUT2 forced 50mV beyond PGOOD1 trip
threshold, falling edge

V

= V

OUT2

impedance), I

OUT2 = REFIN2 (PGOOD2 high impedance),
PGOOD2 forced to 5.5V, T

0.2 2.0 V

With respect to valley current-limit threshold,
SKIP = V

V

OUT1

V

AGND

REFIN2

- VLX_

CC

= V

OUT2

- VLX_, SKIP = GND or OPEN/REF 3 mV

and OUT2 > REFIN2

CC

- 150mV (PGOOD2 low
= 4mA

SINK

= +25°C

A

R

_ = 100k 44 50 56

ILIM

R

_ = 200k 90 100 110

ILIM

_ = 400k 180 200 220

R

ILIM

= V

= 0.77V, V

FB1

REFIN2

= 0.70V 25 mV

13 16 19 %

V

REF

0.20

65 70 75 %

±25 mV

-19 -16 -13 %

-175 -150 -125 mV

10 µs

0.3 V

1 µA

-120 %

+

V

mV

MAX17020

Dual Quick-PWM Step-Down Controller
with Low-Power LDO, RTC Regulator

6 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)

(Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

GATE DRIVERS

DH_ Gate Driver On-Resistance R

DL_ Gate Driver On-Resistance R

DH_ Gate Driver Source/Sink
Current

DL_ Gate Driver Source Current

DL_ Gate Driver Sink Current I

Internal BST_ Switch
On-Resistance

BST_ Leakage Current I

INPUTS AND OUTPUTS

TON Input Logic Level s

SKIP Input Logic Level s

SKIP, TON Leakage Current I

ON_ Input Logic Levels 68mV hysteresis

ON_ Leakage Current I

ONLDO Input Logic Levels 68mV hysteres is

ONLDO Leakage Current I

DH

DL

I

DH

I

DL

(SOURCE)

DL (SINK)

R

BST IBST

BST

SKIP, ITON VSKIP

ON_

ONLDO VONLDO

BST1 - LX1 and BST2 - LX2 forced to 5V 1.5 3.5 

DL1, DL2; high state 2.2 4.5

DL1, DL2; low state 0.6 1.5

DH1, DH2 forced to 2.5V,
BST1 - LX1 and BST2 - LX2 forced to 5V

DL1, DL2 forced to 2.5V 1.7 A

DL1, DL2 forced to 2.5V 3.3 A

_ = 10mA, VDD = 5V 5 

V

_ = 26V, TA = +25°C,

BST

OUT2 and FB1 above regulation threshold

High

REF or open 1.6 3.0

Low 0.4

High (forced-PWM)

Open (ultrasonic) 1.6 3.0

Low (skip) 0.4

V

ON1

= V

= V

= 0 or 5V, TA = +25°C -2 +2 µA

TON

High (SMPS on) 2.4

Low (SMPS off) 0.8

= 0 or 5V, TA = +25°C -2 +2 µA

ON2

High (SMPS on) 2.4

Low (SMPS off) 0.8

= 0 or 24V, TA = +25°C -1 +1 µA

2 A

0.1 5 µA

V

-

CC

0.4V

-

V

CC

0.4V



V

V

V

V

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

_______________________________________________________________________________________ 7

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

INPUT SUPPLIES

IN Standby Supply Current I

IN Shutdown Supply Current I

IN(STBY)

IN( SHDN) VIN

IN Supply Current I

VCC Supply Current I

CC

VIN = 6V to 24V, ON1 = ON2 = GND,
ONLDO = V

CC

= 4.5V to 24V, ON1 = ON2 = ONLDO = GND 70 µA

ON1 = ON2 = REFIN2 = VCC,

IN

SKIP = FB1 = GND, V

ON1 = ON2 = REFIN2 = VCC,
SKIP = FB1 = GND, V

OUT2

OUT2

= 3.5V, V

= 3.5V, V

OUT1

OUT1

= 5.3V

= 5.3V

PWM CONTROLLERS

5V preset output: FB1 = GND,

= 12V, SKIP = V

V

OUT1 Output-Voltage Accuracy
(Note 1)

V

OUT1

V

FB1

IN

1.5V preset output: FB1 = VCC (5V),
V

= 12V, SKIP = V

IN

Adjustable feedback output,
V

= 12V, SKIP = V

IN

CC

CC

CC

OUT1 Voltage-Adjust Range 0.7 5.5 V

FB1 Dual-Mode Threshold
Voltage

Low 0.040 0.125

High

3.3V preset output: REFIN2 = VCC(5V),
V

= 12V, SKIP = V

OUT2 Output-Voltage Accuracy
(Note 1)

V

OUT2

IN

1.05V preset output: REFIN2 = RTC (3.3V),
V

= 1.2V, SKIP = V

IN

Tracking output: V

= 12V, SKIP = V

V

IN

CC

CC

REFIN2

CC

= 1.0V,

OUT2 Voltage-Adjust Range 0 2 V

REFIN2 Voltage-Adjust Range 0 2 V

REFIN2 Dual-Mode Threshold
Voltage

DH1 On-Time t

DH2 On-Time t

Minimum Off-Time t

Ultrasonic Operating Frequency f

OFF(MIN)

SW(USONIC)

SECFB Threshold Voltage V

ON1

ON2

SECFB

Low (REFIN2 = RTC) 2.2 3.0

High (REFIN2 = V

VIN = 12V,

= 5.0V (Note 2)

V

OUT1

VIN = 12V,

= 3.3V (Note 2)

V

OUT2

)

CC

TON = GND or REF
(400kHz)

TON = V

(200kHz) 1895 2315

CC

TON = GND (500kHz) 475 635

TON = REF or V

CC

(300kHz)

(Note 2) 425 ns
SKIP = open (REF) 18 kHz

1.92 2.08 V

200 µA

0.2 mA

1.5 mA

4.90 5.10

1.47 1.53

V

0.685 0.715

V

CC

1.6V

-

V

CC

0.7V

V

-

3.234 3.366

1.029 1.071

V

0.985 1.015

V

CC

1.2V

-

V

CC

0.4V

895 1209

833 1017

V

-

ns

ns

MAX17020

Dual Quick-PWM Step-Down Controller
with Low-Power LDO, RTC Regulator

8 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

LINEAR REGULATOR (LDO)

LDO Output-Voltage Accuracy V

LDO

LDOREFIN Input Range V

LDOREFIN Dual-Mode
Threshold Voltage

LDO Short-Circuit Current I

LDO Regulation Reduction/
Bypass Switchover Threshold

VCC Undervoltage-Lockout
Threshold

3.3V ALWAYS-ON LINEAR REGULATOR (RTC)

RTC Output-Voltage Accuracy V

RTC Short-Circuit Current I

REFERENCE (REF)

Reference Voltage V

Reference Load-Regulation Error V

OUT1 FAULT DETECTION

OUT1 Overvoltage Trip
Threshold

OUT1 Undervoltage-Protection
Trip Threshold

PGOOD1 Lower Trip Threshold

PGOOD1 Output-Low Voltage

OUT2 FAULT DETECTION

OUT2 Overvoltage Trip
Threshold

LDOREFIN VLDO

ILIM(LDO)

V

UVLO(VCC)

RTC

ILIM(RTC)

REF

REF IREF

V

OVP(OUT1)

V

UVP(OUT1)

V

OVP(OUT2)

VIN = 24V, LDOREFIN = BYP = GND,
0mA < I

VIN = 24V, LDOREFIN = VCC, BYP = GND,
0mA < I

VIN = 24V, BYP = GND, V
0mA < I

LDOREFIN low threshold 0.10 0.25

LDOREFIN high threshold

LDO = GND 260 mA

Fal ling edge of BYP -12 -5 %

Fal ling edge of VCC,
PWM disabled below this threshold

ON1 = ON2 = GND, VIN = 6V to 24V,
0 < I

ON1 = ON2 = ONLDO = GND,

= 6V to 24V, 0 < I

V

IN

RTC = GND 5 30 mA

VCC = 4.5V to 5.5V, I

With respect to error-comparator thresho ld 12 20 %

With respect to error-comparator thresho ld 63 77 %

With respect to error-comparator threshold,
falling edge, hysteresis = 1%

V

FB1

I

SINK

Preset mode (REFIN2 = RTC or VCC): with
respect to error-comparator threshold

Tracking mode: with respect to REFIN2 voltage 160 240 mV

< 100mA

LDO

< 100mA

LDO

< 100mA

LDO

= 2x V

LDOR EFI N

< 5mA

RTC

= -20µA to 50µA -10 +10 mV

= 0.56V (PGOOD1 low impedance),

= 4mA

LDOR EFI N

0.3 2.0 V

< 5mA

RTC

= 0 1.975 2.025 V

REF

= 0.5V,

4.85 5.15

3.20 3.40

0.960 1.040

V

-

CC

2V

3.8 4.3 V

3.18 3.45

3.16 3.50

-20 -12 %

0.4 V

12 20 %

VCC -

0.9V

V

V

V

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

_______________________________________________________________________________________ 9

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V

SECFB

= 5V, V

REFIN2

= 1.0V, BYP =

LDOREFIN = GND, ONLDO = IN, ON1 = ON2 = V

CC

, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)

)

Note 1: DC output accuracy specifications refer to the threshold of the error comparator. When the inductor is in continuous conduc-

tion, the MAX17020 regulates the valley of the output ripple, so the actual DC output voltage is higher than the trip level by
50% of the output ripple voltage. In discontinuous conduction (I

OUT

< I

LOAD(SKIP)

), the output voltage has a DC regulation

level higher than the error-comparator threshold by approximately 1.5% due to slope compensation.

Note 2: On-time and off-time specifications are measured from 50% point to 50% point at the DH pin with LX = PGND, V

BST

= 5V,
and a 500pF capacitor from DH to LX to simulate external MOSFET gate capacitance. Actual in-circuit times might be differ­ent due to MOSFET switching speeds.

Note 3: Limits are 100% production tested at T

A

= +25°C. Maximum and minimum limits over temperature are guaranteed by design

and characterization.

Note 4: Specifications increased by 1Ω to account for test measurement error.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUT2 Undervoltage-Protection
Trip Threshold

PGOOD2 Lower Trip Threshold

PGOOD2 Output-Low Voltage

CURRENT LIMIT

ILIM_ Adjustment Range V

Valley Current-Limit Threshold
(Adjustable)

GATE DRIVERS

DH_ Gate Driver On-Resistance R

DL_ Gate Driver On-Resistance R

INPUTS AND OUTPUTS

TON Input Logic Levels

SKIP Input Logic Levels

ON_ Input Logic Levels

ONLDO Input Logic Levels

V

UVP(OUT2

ILIM

V

VALLEYV AGN D

DH

DL

Preset mode: with respect to error-comparator
threshold

Tr acki ng m od e: w i th r esp ect to RE FIN 2 vol tag e -230 -370 mV

Preset mode: with respect to error-comparator
threshold, falling edge, hysteresis = 1%

Tracking mode: with respect to REFIN2
voltage, falling edge, hysteresis = 12mV

V

= V

OUT2

impedance), I

- V

BST1 - LX1 and BST2 - LX2 forced to 5V 3.5 Ω

DL1, DL2; high state 4.5

DL1, DL2; low state 1.5

High

REF or open 1.6 3.0

Low 0.4

High (forced-PWM)

Open (ultrasonic) 1.6 3.0

Low (skip) 0.4

High (SMPS on) 2.4

Low (SMPS off) 0.8

High (LDO on) 2.4

Low (LDO off) 0.8

- 150mV (PGOOD2 low

REFIN2

= 4mA

SINK

R

LX

_

R

R

_ = 100kΩ 40 60

ILIM

_ = 200kΩ 85 115

ILIM

_ = 400kΩ 164 236

ILIM

63 77 %

-20 -12 %

-185 -115 mV

0.2 2.0 V

V

-

CC

0.4V

V

-

CC

0.4V

0.4 V

mV

Ω

V

V

V

V

MAX17020

Dual Quick-PWM Step-Down Controller
with Low-Power LDO, RTC Regulator

10 ______________________________________________________________________________________

Typical Operating Characteristics

(Circuit of Figure 1, VIN= 12V, VDD= VCC= 5V, TON = REF, TA= +25°C, unless otherwise noted.)

5V OUTPUT EFFICIENCY

vs. LOAD CURRENT

100

95

90

85

80

75

70

EFFICIENCY (%)

65

60

55

50

0.01 10

7V

LOAD CURRENT (A)

3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENT

100

5V SMPS ENABLED

95

SKIP MODE

90

85

80

ULTRASONIC

75

70

EFFICIENCY (%)

65

60

55

50

MODE

0.01 10
LOAD CURRENT (A)

12V

20V

SKIP MODE
PWM MODE

10.1

PWM MODE

10.1

12V

100

SKIP MODE

95

MAX17020 toc01

90

85

80

75

70

EFFICIENCY (%)

65

60

55

50

0.01 10

SMPS OUTPUT VOLTAGE DEVIATION

3

MAX17020 toc04

2

1

0

-1

SKIP MODE

OUTPUT VOLTAGE DEVIATION (%)

-2

-3

0.01 10

5V OUTPUT EFFICIENCY

vs. LOAD CURRENT

PWM MODE

ULTRASONIC
MODE

10.1

LOAD CURRENT (A)

vs. LOAD CURRENT

LOW-NOISE
ULTRASONIC

PWM MODE

10.1

LOAD CURRENT (A)

12V

12V

100

5V SMPS ENABLED

95

MAX17020 toc02

90

85

80

75

70

EFFICIENCY (%)

65

60

55

50

0.01 10

1000

MAX17020 toc05

100

10

SWITCHING FREQUENCY (kHz)

1

0.01 10

3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENT

7V

20V

12V

SKIP MODE
PWM MODE

10.1

LOAD CURRENT (A)

SWITCHING FREQUENCY

vs. LOAD CURRENT

PWM MODE

LOW-NOISE
ULTRASONIC
MODE

SKIP MODE

10.1

LOAD CURRENT (A)

MAX17020 toc03

MAX17020 toc06

12V

5V LDO OUTPUT VOLTAGE

vs. LOAD CURRENT

5.2

5.1

5.0

4.9

OUTPUT VOLTAGE (V)

4.8

4.7
020 140

LOAD CURRENT (mA)

100 12040 60 80

MAX17020 toc07

OUTPUT VOLTAGE (V)

3.3V RTC OUTPUT VOLTAGE
vs. LOAD CURRENT

3.5

3.4

3.3

3.2

3.1

3.0
02 12

LOAD CURRENT (mA)

10468

MAX17020 toc08

NO-LOAD INPUT SUPPLY CURRENT

vs. INPUT VOLTAGE

100

PWM MODE

10

SKIP MODE

1

SUPPLY CURRENT (mA)

0.1

0.01
025

INPUT VOLTAGE (V)

LOW-NOISE

ULTRASONIC

15 20510

MAX17020 toc09

MAX17020

Dual Quick-PWM Step-Down Controller

with Low-Power LDO, RTC Regulator

______________________________________________________________________________________ 11

Typical Operating Characteristics (continued)

(Circuit of Figure 1, VIN= 12V, VDD= VCC= 5V, TON = REF, TA= +25°C, unless otherwise noted.)

STANDBY AND SHUTDOWN INPUT

SUPPLY CURRENT vs. INPUT VOLTAGE

1

STANDBY (ONLDO = VIN)

0.1

SUPPLY CURRENT (mA)

SHUTDOWN

(ONLDO = ON1 = ON2 = GND)

0.01
025

INPUT VOLTAGE (V)

15 20510

70

60

MAX17020 toc10

50

40

30

SAMPLE PERCENTAGE (%)

20

10

0

-20 -4-12 4 12 20

100mV ILIM THRESHOLD
VOLTAGE DISTRIBUTION

50

+85°C

+25°C

40

30

20

SAMPLE PERCENTAGE (%)

10

0

90 9894 102 106 110

ILIM THRESHOLD VOLTAGE (mV)

SAMPLE SIZE = 150

12V

MAX17020 toc13

0V

0V

0V

0V

REFERENCE OFFSET

VOLTAGE DISTRIBUTION

+85°C

+25°C

2V REF OFFSET VOLTAGE (mV)

LDO AND RTC POWER-UP

A. INPUT SUPPLY, 5V/div
B. 5V LDO, 2V/div

200μs/div

SAMPLE SIZE = 150

MAX17020 toc14

C. 3.3V RTC, 2V/div
D. 2.0V REF, 1V/div

70

60

MAX17020 toc11

50

40

30

SAMPLE PERCENTAGE (%)

20

10

0

A

12V

12V
B

5V

C

3.3V

D

2.0V

5V

3.3V

2V

REFIN2 OFFSET

VOLTAGE DISTRIBUTION

+85°C

+25°C

-5 -1-3 1 3 5

REFIN2 OFFSET VOLTAGE (mV)

LDO AND RTC POWER REMOVAL

A. INPUT SUPPLY, 5V/div
B. 5V LDO, 2V/div

SAMPLE SIZE = 150

200μs/div

MAX17020 toc15

C. 3.3V RTC, 2V/div
D. 2.0V REF, 1V/div

MAX17020 toc12

A
12V

B
5V

C

3.3V
D

2.0V