MAXIM MAX15004, MAX15005 User Manual

General Description

The MAX15004A/B/MAX15005A/B high-performance,
current-mode PWM controllers operate at an automo­tive input voltage range from 4.5V to 40V (load dump).
The input voltage can go down as low as 2.5V after
startup if VCCis supplied by an external bias voltage.
The controllers integrate all the building blocks neces­sary for implementing fixed-frequency isolated/noniso­lated power supplies. The general-purpose boost,
flyback, forward, and SEPIC converters can be
designed with ease around the MAX15004/MAX15005.

The current-mode control architecture offers excellent
line-transient response and cycle-by-cycle current limit
while simplifying the frequency compensation.
Programmable slope compensation simplifies the
design further. A fast 60ns current-limit response time,
low 300mV current-limit threshold makes the controllers
suitable for high-efficiency, high-frequency DC-DC con­verters. The devices include an internal error amplifier
and 1% accurate reference to facilitate the primary-side
regulated, single-ended flyback converter or nonisolat­ed converters.

An external resistor and capacitor network programs
the switching frequency from 15kHz to 500kHz (1MHz for
the MAX15005A/B). The MAX15004A/B/MAX15005A/B
provide a SYNC input for synchronization to an external
clock. The maximum FET-driver duty cycle for the
MAX15004A/B is 50%. The maximum duty cycle can be
set on the MAX15005A/B by selecting the right combi­nation of RT and CT.

The input undervoltage lockout (ON/OFF) programs the
input-supply startup voltage and can be used to shut­down the converter to reduce the total shutdown cur­rent down to 10µA. Protection features include
cycle-by-cycle and hiccup current limit, output overvolt­age protection, and thermal shutdown.

The MAX15004A/B/MAX15005A/B are available in
space-saving 16-pin TSSOP and thermally enhanced
16-pin TSSOP-EP packages. All devices operate over
the -40°C to +125°C automotive temperature range.

Applications

Automotive

Vacuum Fluorescent Display (VFD) Power
Supply

Isolated Flyback, Forward, Nonisolated SEPIC,
Boost Converters

Features

♦ Wide 4.5V to 40V Operating Input Voltage Range

♦ Operates Down to 2.5V (with Bootstrapped V

CC

Bias)

♦ Current-Mode Control

♦ Low 300mV, 5% Accurate Current-Limit Threshold

Voltage

♦ Internal Error Amplifier with 1% Accurate Reference

♦ RC Programmable 4% Accurate Switching

Frequency

♦ Switching Frequency Adjustable from 15kHz to

500kHz (1MHz for the MAX15005A/B)

♦ External Frequency Synchronization

♦ 50% (MAX15004) or Adjustable (MAX15005)

Maximum Duty Cycle

♦ Programmable Slope Compensation

♦ 10µA Shutdown Current

♦ Cycle-by-Cycle and Hiccup Current-Limit

Protection

♦ Overvoltage and Thermal Shutdown Protection

♦ -40°C to +125°C Automotive Temperature Range

♦ 16-Pin TSSOP or 16-Pin Thermally Enhanced

TSSOP-EP Packages

♦ AEC-Q100 Qualified

MAX15004/MAX15005

4.5V to 40V Input Automotive

Flyback/Boost/SEPIC Power-Supply Controllers

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

19-0723; Rev 3; 1/11

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.

Note: All devices are specified over the -40°C to +125°C

temperature range.

+

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

/V denotes an automotive qualified part.

*

EP = Exposed pad.

Pin Configurations appear at end of data sheet.

EVALUATION KIT

AVAILABLE

PART PIN-PACKAGE MAX DUTY CY CLE

MAX15004AAUE+ 16 TSSOP-EP* 50%

MAX15004AAUE/V+ 16 TSSOP-EP* 50%

MAX15004BAUE+ 16 TSSOP 50%

MAX15004BAUE/V+ 16 TSSOP 50%

MAX15005AAUE+ 16 TSSOP-EP* Programmable

MAX15005AAUE/V+ 16 TSSOP-EP* Programmable

MAX15005BAUE+ 16 TSSOP Programmable

MAX15005BAUE/V+ 16 TSSOP Programmable

MAX15004/MAX15005

4.5V to 40V Input Automotive
Flyback/Boost/SEPIC Power-Supply Controllers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ, CT =

560pF, V

SYNC

= V

OVI

= VFB= VCS= 0V, COMP = unconnected, OUT = unconnected. TA= TJ= -40°C to +125°C, unless otherwise

noted. Typical values are at T

A

= +25°C. All voltages are referenced to PGND, unless otherwise noted.) (Note 1) (Figure 5)

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 to SGND.............................................................-0.3V to +45V

IN to PGND.............................................................-0.3V to +45V

ON/OFF to SGND ........................................-0.3V to (V

IN

+ 0.3V)

OVI, SLOPE, RTCT, SYNC, SS, FB, COMP,

CS to SGND.........................................-0.3V to (V

REG5

+ 0.3V)

V

CC

to PGND..........................................................-0.3V to +12V

REG5 to SGND .........................................................-0.3V to +6V

OUT to PGND.............................................-0.3V to (V

CC

+ 0.3V)

SGND to PGND .....................................................-0.3V to +0.3V

V

CC

Sink Current (clamped mode).....................................35mA

OUT Current (< 10μs transient) ..........................................±1.5A

Continuous Power Dissipation* (T

A

= +70°C)
16-Pin TSSOP-EP (derate 21.3mW/°C

above +70°C)..............................................................1702mW

16-Pin TSSOP (derate 9.4mW/°C above +70°C) ..........754mW

Operating Junction Temperature Range...........-40°C to +125°C

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

Storage Temperature Range .............................-60°C to +150°C

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

Soldering Temperature (reflow) .......................................+260°C

*

As per JEDEC51 Standard, Multilayer Board.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

POWER SUPPLY

Input Supply Range V

Operating Supply Current I

ON/OFF CONTROL

Input-Voltage Threshold V

Input-Voltage Hysteresis V

Input Bias Current I

Shutdown Current I

INTERNAL 7.4V LDO (VCC)

Output (VCC) Voltage Set Point V

Line Regulation VIN = 8V to 40V 1 mV/V

UVLO Threshold Voltage V

UVLO Hysteresis V

Dropout Voltage VIN = 4.5V, I

Output Current Limit I

Internal Clamp Voltage V

INTERNAL 5V LDO (REG5)

IN

Q

ON

HYST-ON

B-ON/OFFVON/OFF

SHDN

VCC

UVLO-VCCVCC

HYST-UVLO

VCC-ILIMIVCC

VCC-CLAMPIVCC

VIN = 40V, f

V

ON/OFF

V

ON/OFF

I

VCC

OSC

rising 1.05 1.23 1.40 V

= 40V 0.5 μA

= 0V 10 20 μA

= 0 to 20mA (sourcing) 7.15 7.4 7.60 V

rising 3.15 3.5 3.75 V

VCC

sourcing 45 mA

= 30mA (sinking) 10.0 10.4 10.8 V

= 150kHz 2 3.1 mA

= 20mA (sourcing) 0.25 0.5 V

4.5 40.0 V

75 mV

500 mV

Output (REG5) Voltage Set Point V

Line Regulation VCC = 5.5V to 10V 2 mV/V

Dropout Voltage VCC = 4.5V, I

Output Current Limit I

REG5

REG5-ILIMIREG5

VCC = 7.5V, I

sourcing 32 mA

= 0 to 15mA (sourcing) 4.75 4.95 5.05 V

REG5

= 15mA (sourcing) 0.25 0.5 V

REG5

MAX15004/MAX15005

4.5V to 40V Input Automotive

Flyback/Boost/SEPIC Power-Supply Controllers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ, CT =

560pF, V

SYNC

= V

OVI

= VFB= VCS= 0V, COMP = unconnected, OUT = unconnected. TA= TJ= -40°C to +125°C, unless otherwise

noted. Typical values are at T

A

= +25°C. All voltages are referenced to PGND, unless otherwise noted.) (Note 1) (Figure 5)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OSCILLATOR (RTCT)

Oscillator Frequency Range f

RTCT Peak Trip Level V

RTCT Valley Trip Level V

RTCT Discharge Current I

Oscillator Frequency Accuracy
(Note 2)

Maximum PWM Duty Cycle
(Note 3)

Minimum On-Time t

SYNC Lock-In Frequency Range
(Note 4)

SYNC High-Level Voltage V

SYNC Low-Level Voltage V

SYNC Input Current I

SYNC Minimum Input Pulse Width 50 ns

ERROR AMPLIFIER/SOFT-START

Soft-Start Charging Current I

SS Reference Voltage V

SS Threshold for HICCUP Enable VSS rising 1.1 V

FB Regulation Voltage V

FB Input Offset Voltage V

FB Input Current VFB = 0 to 1.5V -300 +300 nA

COMP Sink Current I

OSC

TH,RTCT

TL,RTCT

DIS,RTCTVRTCT

f
f

OSC

OSC

= 2 x f

OUT

= f

for MAX15005A/B

OUT

for MAX15004A/B,

= 2V 1.30 1.33 1.36 mA

RT = 13.7kΩ, CT = 4.7nF,
f

(typ) = 18kHz

OSC

RT = 13.7kΩ, CT = 560pF,
f

(typ) = 150kHz

OSC

RT = 21kΩ, CT = 100pF,

(typ) = 500kHz

f

OSC

RT = 7kΩ, CT = 100pF,
f

(typ) = 1MHz

OSC

15 1000 kHz

0.55 x V

0.1 x V

REG5

REG5

-4 +4

-4 +4

-5 +5

-7 +7

MAX15004A/B 50

D

MAX

ON-MIN

IH-SYNC

IL-SYNC

SYNC

SS

SS

REF-FB

MAX15005A/B,
RT = 13.7kΩ, CT = 560pF,
f

(typ) = 150kHz

OSC

78.5 80 81.5

VIN = 14V 110 170 ns
RT = 13.7kΩ, CT = 560pF,

f

(typ) = 150kHz

OSC

102 200 %f

2V

V

= 0 to 5V -0.5 +0.5 μA

SYNC

VSS = 0V 8 15 21 μA

1.215 1.228 1.240 V

COMP = FB,

= -500μA to +500μA

I

COMP

1.215 1.228 1.240 V

COMP = 0.25V to 4.5V,

= -500μA to +500μA,

I

OS-FB

COMP-SINKVFB

COMP

V

SS

= 0 to 1.5V

= 1.5V, V

= 0.25V 3 5.5 mA

COMP

-5 +5 mV

0.8 V

V

V

%

%

OSC

MAX15004/MAX15005

4.5V to 40V Input Automotive
Flyback/Boost/SEPIC Power-Supply Controllers

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ, CT =

560pF, V

SYNC

= V

OVI

= VFB= VCS= 0V, COMP = unconnected, OUT = unconnected. TA= TJ= -40°C to +125°C, unless otherwise

noted. Typical values are at T

A

= +25°C. All voltages are referenced to PGND, unless otherwise noted.) (Note 1) (Figure 5)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

COMP Source Current

COMP High Voltage V

COMP Low Voltage V

Open-Loop Gain A

Unity-Gain Bandwidth UGF

Phase Margin PM

COMP Positive Slew Rate SR+ 0.5 V/μs

COMP Negative Slew Rate SR- -0.5 V/μs

PWM COMPARATOR

Current-Sense Gain A

PWM Propagation Delay to OUT t

I

COMP-

SOURCE

OH-COMPVFB

OL-COMPVFB

EAMP

EAMP

EAMP

CS-PWM

PD-PWM

VFB = 1V, V

= 1V, I

COMP

COMP

= 1.5V, I

ΔV

COMP

/ΔV

CS

CS = 0.15V, from V

= 4.5V 1.3 2.8 mA

= 1mA (sourcing)

= 1mA (sinking) 0.1 0.25 V

COMP

(Note 5) 2.85 3 3.15 V/V

falling edge:

COMP

3V to 0.5V to OUT falling (excluding

V

REG5

- 0.5

V

REG5

- 0.2

100 dB

1.6 MHz

75 degrees

60 ns

leading-edge blanking time)

V

PWM Comparator Current-Sense
Leading-Edge Blanking Time

t

CS-BLANK

50 ns

CURRENT-LIMIT COMPARATOR

Current-Limit Threshold Voltage V

Current-Limit Input Bias Current I

ILIMIT Propagation Delay to OUT t

ILIM

B-CS

PD-ILIM

OUT= high, 0 ≤ VCS ≤ 0.3V -2 +2 μA

From CS rising above V

ILIM

(50mV

overdrive) to OUT falling (excluding

290 305 317 mV

60 ns

leading-edge blanking time)

ILIM Comparator Current-Sense
Leading-Edge Blanking Time

Number of Consecutive ILIMIT
Events to HICCUP

t

CS-BLANK

50 ns

7

HICCUP Timeout 512

SLOPE COMPENSATION (Note 6)

Slope Capacitor Charging
Current

Slope Compensation C

Slope Compensation Tolerance
(Note 2)

Slope Compensation Range

I

SLOPE

V

= 100mV 9.8 10.5 11.2 μA

SLOPE

= 100pF 25 mV/μs

SLOPE

C

= 100pF -4 +4 %

SLOPE

C

= 22pF 110

SLOPE

= 1000pF 2.5

C

SLOPE

Clock

periods

mV/μs

MAX15004/MAX15005

4.5V to 40V Input Automotive

Flyback/Boost/SEPIC Power-Supply Controllers

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS (continued)

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ, CT =

560pF, V

SYNC

= V

OVI

= VFB= VCS= 0V, COMP = unconnected, OUT = unconnected. TA= TJ= -40°C to +125°C, unless otherwise

noted. Typical values are at T

A

= +25°C. All voltages are referenced to PGND, unless otherwise noted.) (Note 1) (Figure 5)

Note 1: 100% production tested at +125°C. Limits over the temperature range are guaranteed by design.
Note 2: Guaranteed by design; not production tested.
Note 3: For the MAX15005A/B, D

MAX

depends upon the value of RT. See Figure 3 and the

Oscillator Frequency/External

Synchronization

section.

Note 4: The external SYNC pulse triggers the discharge of the oscillator ramp. See Figure 2. During external SYNC, D

MAX

= 50% for

the MAX15004A/B; for the MAX15005A/B, there is a shift in D

MAX

with f

SYNC/fOSC

ratio (see the

Oscillator Frequency/

External Synchronization

section).

Note 5: The parameter is measured at the trip point of latch, with 0 ≤ V

CS

≤ 0.3V, and FB = COMP.

Note 6: Slope compensation = (2.5 x 10

-9

)/C

SLOPE

mV/μs. See the

Applications Information

section.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUTPUT DRIVER

Driver Output Impedance

Driver Peak Output Current I

OVERVOLTAGE COMPARATOR

Overvoltage Comparator Input
Threshold

Overvoltage Comparator
Hysteresis

Overvoltage Comparator Delay TD

OVI Input Current I

THERMAL SHUTDOWN

Shutdown Temperature T

Thermal Hysteresis T

R

OUT-N

R

OUT-P

OUT-PEAK

V

OV-TH

V

OV-HYST

OVI

OVI

SHDN

HYST

VCC = 8V (applied externally),

= 100mA (sinking)

I

OUT

VCC = 8V (applied externally),

= 100mA (sourcing)

I

OUT

C

= 10nF, sinking 1000

OUT

C

= 10nF, sourcing 750

OUT

V

rising 1.20 1.228 1.26 V

OVI

From OVI rising above 1.228V to OUT
falling, with 50mV overdrive

V

= 0 to 5V -0.5 +0.5 μA

OVI

Temperature rising 160

1.7 3.5

35

125 mV

1.6 μs

15

Ω

mA

o

C

o

C

MAX15004/MAX15005

4.5V to 40V Input Automotive
Flyback/Boost/SEPIC Power-Supply Controllers

6 _______________________________________________________________________________________

Typical Operating Characteristics

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ,

CT = 560pF. TA = +25°C, unless otherwise noted.)

VIN UVLO HYSTERESIS

vs. TEMPERATURE

TEMPERATURE (°C)

V

IN

UVLO HYSTERESIS (mV)

MAX15004 toc01

-40 -15 10 35 60 85 110 135

0

10

20

30

40

50

60

70

80

90

100

110

120

VIN SUPPLY CURRENT (I

SUPPLY

)

vs. OSCILLATOR FREQUENCY (f

OSC

)

FREQUENCY (kHz)

V

IN

SUPPLY CURRENT (mA)

MAX15004 toc02

10 60 110 160 210 260 310 360 410 460 510

1

4

7

10

13

16

19

22

25

28

31

MAX15005
V

IN

= 14V

CT = 220pF

C

OUT

= 10nF

C

OUT

= 0nF

SHUTDOWN SUPPLY CURRENT

vs. SUPPLY VOLTAGE

SUPPLY VOLTAGE (V)

V

IN

SHUTDOWN SUPPLY CURRENT (μA)

MAX15004 toc03

5 1015202530354045

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

TA = +135°C

TA = -40°C

TA = +25°C

V

CC

OUTPUT VOLTAGE

vs. V

IN

SUPPLY VOLTAGE

VIN SUPPLY VOLTAGE (V)

V

CC

OUTPUT VOLTAGE (V)

MAX15004 toc04

5 1015202530354045

5.0

5.5

6.0

6.5

7.0

7.5

I

VCC

= 0mA

I

VCC

= 1mA

I

VCC

= 20mA

VCC CLAMP VOLTAGE

vs. V

CC

CURRENT SINK (I

VCC

)

VCC CURRENT SINK (mA)

V

CC

CLAMP VOLTAGE (V)

MAX15004 toc05

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

7.00

7.25

7.50

7.75

8.00

8.25

8.50

8.75

9.00

9.25

9.50

9.75

10.00

10.25

10.50

TA = +135°C

TA = -40°C

TA = +25°C

TA = +125°C

REG5 OUTPUT VOLTAGE

vs. V

CC

VOLTAGE

VCC VOLTAGE (V)

REG5 OUTPUT VOLTAGE (V)

MAX15004 toc06

5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5

4.700

4.725

4.750

4.775

4.800

4.825

4.850

4.875

4.900

4.925

4.950

4.975

5.000
I

REG5

= 1mA (SOURCING)

I

REG5

= 15mA (SOURCING)

REG5 DROPOUT VOLTAGE

vs. I

REG5

I

REG5

(mA)

REG5 LDO DROPOUT VOLTAGE (V)

MAX15004 toc07

0 2 4 6 8 10 12 14

0

0.03

0.05

0.08

0.10

0.13

0.15

0.18

0.20

0.23

0.25

0.28

0.30

TA = +135°C

TA = +25°C

TA = -40°C

TA = +125°C

VCC = 4.5
V

IN

= V

ON/OFF

OSCILLATOR FREQUENCY (f

OSC

)

vs. V

IN

SUPPLY VOLTAGE

VIN SUPPLY VOLTAGE (V)

OSCILLATOR FREQUENCY (kHz)

MAX15004 toc08

5.5 10.5 15.5 20.5 25.5 30.5 35.5 40.5 45.5

140

141

142

143

144

145

146

147

148

149

150

TA = +125°C

TA = -40°C

TA = +25°C

TA = +135°C

RT = 13.7kΩ
CT = 560pF

MAX15005

OSCILLATOR FREQUENCY (f

OSC

)

vs. RT/CT

RT (kΩ)

OSCILLATOR FREQUENCY (kHz)

MAX15004 toc09

1 10 100 1000

10

100

1000

CT = 220pF

CT = 1500pF

CT = 1000pF

CT = 560pF

CT = 2200pF

CT = 3300pF

CT = 100pF

MAX15004/MAX15005

OVI TO OUT DELAY THROUGH
OVERVOLTAGE COMPARATOR

MAX15004 toc16

1μs/div

V

OUT

2V/div

V

OVI

500mV/div

V

OUT

V

OVI

DRIVER OUTPUT PEAK SOURCE

AND SINK CURRENT

MAX15004 toc17

400ns/div

V

OUT

5V/div

I

OUT

1A/div

C

OUT

= 10nF

POWER-UP SEQUENCE THROUGH V

IN

MAX15004 toc18

2ms/div

V

IN

10V/div
V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

V

ON/OFF

= 5V

4.5V to 40V Input Automotive

Flyback/Boost/SEPIC Power-Supply Controllers

_______________________________________________________________________________________

7

Typical Operating Characteristics (continued)

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ,

CT = 560pF. TA = +25°C, unless otherwise noted.)

MAX15005 MAXIMUM DUTY CYCLE

vs. OUTPUT FREQUENCY (f

100

95

90

85

80

CT = 3300pF

75

70

CT = 2200pF

65

CT = 1500pF

MAXIMUM DUTY CYCLE (%)

60

CT = 1000pF

55

50

10 100 1000

CT = 560pF

OUTPUT FREQUENCY (kHz)

MAXIMUM DUTY CYCLE

vs. f

SYNC/fOSC

80

MAX15005

75

70

65

C

= 220pF

60

MAXIMUM DUTY CYCLE (%)

55

50

RTCT

= 10kΩ

R

RTCT

= f

= 418kHz

f

OSC

OUT

1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0
f

SYNC/fOSC

CT = 220pF

RATIO

CT = 560pF
RT = 10kΩ

= f

f

OSC

OUT

RATIO

CT = 100pF

)

OUT

MAX15004 toc10

MAXIMUM DUTY CYCLE (%)

MAX15004 toc13

= 180kHz

GAIN (dB)

55

54

53

52

51

50

49

48

47

46

45

110
100

90
80
70
60
50
40
30
20
10

0

-10

MAX15004 MAXIMUM DUTY CYCLE

vs. TEMPERATURE

f

= 75kHz

OUT

-40 -15 10 35 60 85 110 135

TEMPERATURE (°C)

ERROR AMPLIFIER OPEN-LOOP GAIN

AND PHASE vs. FREQUENCY

GAIN

PHASE

0.1 1 10 100 1k 10k 100k 1M 10M
FREQUENCY (Hz)

MAX15004 toc14

MAX15004 toc11

340

300

260

220

180

140

100

60

MAX15005 MAXIMUM DUTY CYCLE

85

CT = 560pF

83

RT = 13.7kΩ
f

OSC

81

79

77

75

73

71

MAXIMUM DUTY CYCLE (%)

69

67

65

-40 -15 10 35 60 85 110 135

CS-TO-OUT DELAY vs. TEMPERATURE

100

90

80

70

60

50

40

PHASE (DEGREES)

30

CS-TO-OUT DELAY (ns)

20

10

0

-40 -15 10 35 60 85 110 135

vs. TEMPERATURE

= f

= 150kHz

OUT

TEMPERATURE (°C)

VCS OVERDRIVE = 50mV

VCS OVERDRIVE = 190mV

TEMPERATURE (°C)

MAX15004 toc12

MAX15004 toc15

MAX15004/MAX15005

4.5V to 40V Input Automotive
Flyback/Boost/SEPIC Power-Supply Controllers

8 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VIN= 14V, CIN= 0.1μF, C

VCC

= 0.1μF // 1μF, C

REG5

= 1μF, V

ON/OFF

= 5V, CSS= 0.01μF, C

SLOPE

= 100pF, RT = 13.7kΩ,

CT = 560pF. TA = +25°C, unless otherwise noted.)

HICCUP MODE FOR FLYBACK CIRCUIT

(FIGURE 7)

MAX15004 toc24

10ms/div

V

CS

200mV/div

V

ANODE

1V/div

I

SHORT

500mA/div

DRAIN WAVEFORM IN

FLYBACK CONVERTER (FIGURE 7)

MAX15004 toc25

4μs/div

10V/div

I

LOAD

= 10mA

LINE TRANSIENT FOR VIN STEP

FROM 14V TO 5.5V

MAX15004 toc22

100μs/div

V

IN

10V/div

V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

LINE TRANSIENT FOR VIN STEP

FROM 14V TO 40V

MAX15004 toc23

100μs/div

V

IN

20V/div

V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

POWER-DOWN SEQUENCE THROUGH V

MAX15004 toc19

V

= 5V

ON/OFF

IN

V

IN

10V/div

V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

POWER-UP SEQUENCE

THROUGH ON/OFF

MAX15004 toc20

ON/OFF
5V/div

V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

POWER-DOWN SEQUENCE

THROUGH ON/OFF

MAX15004 toc21

ON/OFF
5V/div

V

CC

5V/div

REG5
5V/div

V

OUT

5V/div

4ms/div

1ms/div

400ms/div

MAX15004/MAX15005

4.5V to 40V Input Automotive

Flyback/Boost/SEPIC Power-Supply Controllers

_______________________________________________________________________________________ 9

Pin Description

PIN NAME FUNCTION

1 IN Input Power Supply. Bypass IN with a minimum 0.1μF ceramic capacitor to PGND.

ON/OFF Input. Connect ON/OFF to IN for always-on operation. To externally program the UVLO threshold of the

2 ON/OFF

3 OVI

4 SLOPE

5 N.C. No Connection. Not internally connected.

6 RTCT

7 SGND Signal Ground. Connect SGND to SGND plane.

8 SYNC External-Clock Synchronization Input. Connect SYNC to SGND when not using an external clock.

9 SS Soft-Start Capacitor Input. Connect a capacitor from SS to SGND to set the soft-start time interval.

10 FB Internal Error-Amplifier Inverting Input. The noninverting input is internally connected to SS.

11 COMP Error-Amplifier Output. Connect the frequency compensation network between FB and COMP.

12 CS

13 REG5 5V Low-Dropout Regulator Output. Bypass REG5 with a 1μF ceramic capacitor to SGND.

14 PGND Power Ground. Connect PGND to the power ground plane.

15 OUT Gate Driver Output. Connect OUT to the gate of the external n-channel MOSFET.

16 V

—EP

CC

IN supply, connect a resistive divider between IN, ON/OFF, and SGND. Pull ON/OFF to SGND to disable the
controller.

Overvoltage Comparator Input. Connect a resistive divider between the output of the power supply, OVI, and
SGND to set the output overvoltage threshold.

Programmable Slope Compensation Capacitor Input. Connect a capacitor (C
of slope compensation.
Slope compensation = (2.5 x 10

Oscillator-Timing Network Input. Connect a resistor from RTCT to REG5 and a capacitor from RTCT to SGND to
set the oscillator frequency (see the Oscillator Frequency/External Synchronization section).

Current-Sense Input. The current-sense signal is compared to a signal proportional to the error-amplifier output
voltage.

7.4V Low-Dropout Regulator Output—Driver Power Source. Bypass VCC with 0.1μF and 1μF or higher ceramic
capacitors to PGND.

Exposed Pad (MAX15004A/MAX15005A only). Connect EP to the SGND plane to improve thermal performance.
Do not use the EP as an electrical connection.

-9

) / C

SLOPE

mV/μs with C

SLOPE

in farads.

) to SGND to set the amount

SLOPE