Datasheet MC 44603 AP Datasheet

MC44603A

Enhanced Mixed Frequency
Mode GreenLinet PWM
Controller:

Fixed Frequency, Variable Frequency,
Standby Mode

The MC44603A is an enhanced high performance controller that is
specifically designed for off−line and dc−to−dc converter applications.
This device has the unique ability of automatically changing operating
modes if the converter output is overloaded, unloaded, or shorted,
offering the designer additional protection for increased system
reliability. The MC44603A has several distinguishing features when
compared to conventional SMPS controllers. These features consist of
a foldback facility for overload protection, a standby mode when the
converter output is slightly loaded, a demagnetization detection for
reduced switching stresses on transistor and diodes, and a high current
totem pole output ideally suited for driving a power MOSFET. It can
also be used for driving a bipolar transistor in low power converters
(< 150 W). It is optimized to operate in discontinuous mode but can
also operate in continuous mode. Its advanced design allows use in
current mode or voltage mode control applications.

Features

• Pb−Free Packages are Available*

Current or Voltage Mode Controller

• Operation up to 250 kHz Output Switching Frequency

• Inherent Feed Forward Compensation

• Latching PWM for Cycle−by−Cycle Current Limiting

• Oscillator with Precise Frequency Control

High Flexibility

• Externally Programmable Reference Current

• Secondary or Primary Sensing7

• Synchronization Facility

• High Current Totem Pole Output

• Undervoltage Lockout with Hysteresis

Safety/Protection Features

• Overvoltage Protection Against Open Current and Open Voltage Loop

• Protection Against Short Circuit on Oscillator Pin

• Fully Programmable Foldback

• Soft−Start Feature

• Accurate Maximum Duty Cycle Setting

• Demagnetization (Zero Current Detection) Protection

• Internally Trimmed Reference

• Enhanced Output Drive

GreenLine Controller: Low Power Consumption in Standby Mode

• Low Startup and Operating Current

• Fully Programmable Standby Mode

• Controlled Frequency Reduction in Standby Mode

• Low dV/dT for Low EMI Radiations

*For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting

Techniques Reference Manual, SOLDERRM/D.

16

1

16

Foldback Input

Protection (OVP)

Current Sense Input

Demag Detection

See detailed ordering and shipping information in the package
dimensions section on page 21 of this data sheet.

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16

PDIP−16

P SUFFIX

CASE 648

SOIC−16

1

DW SUFFIX
CASE 751G

A = Assembly Location
WL = Wafer Lot
YY = Year
WW = Work Week
G = Pb−Free Package

1

16

1

PIN CONNECTIONS

1 16

V

CC

Output

GND

Overvoltage

2

V

C

3

4

5

6

7

8

(Top View)

15

14

13

12

11

10

9

ORDERING INFORMATION

MARKING

DIAGRAMS

MC44603AP

AWLYYWWG

MC44603ADW

AWLYYWWG

R

ref

R

Frequency

Standby
Voltage Feedback
Input

Error Amp Output

R

Power Standby

Soft−Start/D
Voltage Mode

C

Sync Input

max

T

/

© Semiconductor Components Industries, LLC, 2005

November, 2005 − Rev. 4

1 Publication Order Number:

MC44603A/D

MC44603A

MAXIMUM RATINGS

Rating Symbol Value Unit

Total Power Supply and Zener Current (ICC + IZ) 30 mA
Supply Voltage with Respect to Ground (Pin 4) V

C

V

CC

Output Current (Note 1) mA

Source I
Sink I

O(Source)

O(Sink)

Output Energy (Capacitive Load per Cycle) W 5.0
R

, CT, Soft−Start, R

F Stby

Foldback Input, Current Sense Input,

, R

ref

Inputs V

P Stby

in

V

in

E/A Output, Voltage Feedback Input,
Overvoltage Protection, Synchronization Input

Synchronization Input

High State Voltage V
Low State Reverse Current V

IH
IL

Demagnetization Detection Input Current mA

Source I
Sink I

Error Amplifier Output Sink Current I

demag−ib (Source)

demag−ib (Sink)

E/A (Sink)

Power Dissipation and Thermal Characteristics

P Suffix, Dual−In−Line, Case 648

Maximum Power Dissipation at TA = 85°C P
Thermal Resistance, Junction−to−Air

D

R



JA

DW Suffix, Surface Mount, Case 751G

Maximum Power Dissipation at TA = 85°C P

Thermal Resistance, Junction−to−Air
Operating Junction Temperature T
Operating Ambient Temperature T

D

R



JA
J

A

Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit
values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied,
damage may occur and reliability may be affected.

1. ESD data available upon request.

18 V

−750
750

−0.3 to 5.5 V

−0.3 to V

CC

+ 0.3

VCC + 0.3 V

−20 mA

−4.0
10
20 mA

0.6 W

100 °C/W

0.45 W

145 °C/W
150 °C

−25 to +85 °C

J

V

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MC44603A

ELECTRICAL CHARACTERISTICS (V

and VC = 12 V, (Note 2), R

CC

= 10 k, CT = 820 pF, for typical values TA =

ref

25°C, for min/max values TA = −25° to +85°C (Note 3), unless otherwise noted.)

Characteristic Symbol Min Typ Max Unit

OUTPUT SECTION

Output Voltage (Note 4) V

Low State (I

Low State (I

High State (I

High State (I

Output Voltage During Initialization Phase

VCC = 0 to 1.0 V, I
VCC = 1.0 to 5.0 V, I

VCC = 5.0 to 13 V, I
Output Voltage Rising Edge Slew−Rate (CL = 1.0 nF, TJ = 25°C) dVo/dT − 300 −
Output Voltage Falling Edge Slew−Rate (CL = 1.0 nF, TJ = 25°C) dVo/dT − −300 −

= 100 mA)

Sink

= 500 mA)

Sink

Source
Source

= 200 mA)
= 500 mA)

= 10 A

Sink

= 100 A

Sink

= 1.0 mA

Sink

V

OL

V

OH

V

OL

−

−

−

−

−

−

−

1.0

1.4

1.5

2.0

0.1

0.1

1.2

2.0

2.0

2.7

−

1.0

1.0

1.0
V/s

V/s

ERROR AMPLIFIER SECTION

Voltage Feedback Input (V
Input Bias Current (VFB = 2.5 V) I
Open Loop Voltage Gain (V

= 2.5 V) V

E/A out

= 2.0 to 4.0 V) A

E/A out

FB

FB−ib

VOL

2.42 2.5 2.58 V

−2.0 −0.6 −
65 70 − dB

Unity Gain Bandwidth BW MHz

TJ = 25°C − 4.0 −
TJ = −25° to +85°C − − 5.5

Voltage Feedback Input Line Regulation (VCC = 10 to 15 V) V

FBline−reg

−10 − 10 mV

Output Current mA

Sink (V

= 1.5 V, VFB = 2.7 V)

E/A out

I

Sink

2.0 12 −

TA = −25° to +85°C

Source (V

= 5.0 V, VFB = 2.3 V)

E/A out

I

Source

−2.0 − −0.2

TA = −25° to +85°C

Output Voltage Swing V

High State (I
Low State (I

E/A out (source)

E/A out (sink)

= 0.5 mA, VFB = 2.3 V) V

= 0.33 mA, VFB = 2.7 V) V

OH
OL

5.5 6.5 7.5

− 1.0 1.1

REFERENCE SECTION

Reference Output Voltage (VCC = 10 to 15 V) V
Reference Current Range (I
Reference Voltage Over I

ref

Range

ref

= V

, R = 5.0 k to 25 k)

ref/Rref

V

ref

I

ref

ref

2.4 2.5 2.6 V

−500 − −100

−40 − 40 mV

OSCILLATOR AND SYNCHRONIZATION SECTION

Frequency f

OSC

TA = 0° to +70°C 44.5 48 51.5

TA = −25° to +85°C 44 − 52
Frequency Change with Voltage (VCC = 10 to 15 V)
Frequency Change with Temperature (TA = −25° to +85°C)

f

/V

OSC

f

/T

OSC

− 0.05 − %/V

− 0.05 − %/°C

2. Adjust VCC above the startup threshold before setting to 12 V.

3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

4. VC must be greater than 5.0 V.

5. Standby is disabled for V

6. If not used, Synchronization input must be connected to Ground.

7. Synchronization Pulse Width must be shorter than t

8. This function can be inhibited by connecting Pin 8 to GND. This allows a continuous current mode operation.

< 25 mV typical.

R P Stby

OSC

= 1/f

OSC

.

9. This function can be inhibited by connecting Pin 5 to VCC.

10.The MC44603A can be shut down by connecting the Soft−Start pin (Pin 11) to Ground.

V

A

A

kHz

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MC44603A

ELECTRICAL CHARACTERISTICS (continued) (V

and VC = 12 V, (Note 2), R

CC

= 10 k, CT = 820 pF, for typical values TA =

ref

25°C, for min/max values TA = −25° to +85°C (Note 3), unless otherwise noted.)

Characteristic UnitMaxTypMinSymbol

OSCILLATOR AND SYNCHRONIZATION SECTION

Oscillator Voltage Swing (Peak−to−Peak) V
Ratio Charge Current/Reference Current I

OSC(pp)

charge/Iref

1.65 1.8 1.95 V

TA = 0° to +70°C (VCT = 2.0 V) 0.375 0.4 0.425

TA = −25° to +85°C 0.37 − 0.43
Fixed Maximum Duty Cycle = I
Ratio Standby Discharge Current versus I

TA = 0° to +70°C I

discharge

/(I

discharge

R F Stby

+ I

) D 78 80 82 %

charge

(Note 5) I

disch−Stby

R F Stby

/ −

0.46 0.53 0.6

TA = −25° to +85°C (Note 8) 0.43 − 0.63
V

R F Stby

(I

R F Stby

= 100 A)

Frequency in Standby Mode (R

(Pin 15) = 25 k)

F Stby

V

Current Range I
Synchronization Input Threshold Voltage (Note 6) V

Synchronization Input Current I
Minimum Synchronization Pulse Width (Note 7) t

R F Stby

F

Stby

R F Stby

inthH

V

inthL

Sync−in

Sync

2.4 2.5 2.6 V
18 21 24 kHz

−200 − −50

3.2

0.45

3.7

0.7

4.3

0.9

−5.0 − 0

− − 0.5

UNDERVOLTAGE LOCKOUT SECTION

Startup Threshold V
Output Disable Voltage After Threshold Turn−On (UVLO 1) V

stup−th

disable1

13.6 14.5 15.4 V

TA = 0° to +70°C 8.6 9.0 9.4
TA = −25° to +85°C 8.3 − 9.6

Reference Disable Voltage After Threshold Turn−On (UVLO 2) V

disable2

7.0 7.5 8.0 V

DEMAGNETIZATION DETECTION SECTION (Note 8)

Demagnetization Detect Input

Demagnetization Comparator Threshold (V

Decreasing) V

Pin 9

demag−th

50 65 80 mV

Propagation Delay (Input to Output, Low to High) − − 0.25 −

Input Bias Current (V
Negative Clamp Level (I
Positive Clamp Level (I

= 65 mV) I

demag

= −2.0 mA) C

demag

= 2.0 mA) C

demag

demag−lb

L(neg)

L(pos)

−0.5 − −

− −0.38 − V

− 0.72 − V

SOFT−START SECTION (Note 10)

Ratio Charge Current/I

ref

I

ss(ch)/Iref

TA = 0° to +70°C 0.37 0.4 0.43

TA = −25° to +85°C 0.36 − 0.44
Discharge Current (V
Clamp Level V

= 1.0 V) I

soft−start

discharge

ss(CL)

1.5 5.0 − mA

2.2 2.4 2.6 V

2. Adjust VCC above the startup threshold before setting to 12 V.

3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

4. VC must be greater than 5.0 V.

5. Standby is disabled for V

6. If not used, Synchronization input must be connected to Ground.

7. Synchronization Pulse Width must be shorter than t

8. This function can be inhibited by connecting Pin 8 to GND. This allows a continuous current mode operation.

< 25 mV typical.

R P Stby

OSC

= 1/f

OSC

.

9. This function can be inhibited by connecting Pin 5 to VCC.

10.The MC44603A can be shut down by connecting the Soft−Start pin (Pin 11) to Ground.

−

A

V

A
s

V

s
A

−

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MC44603A

ELECTRICAL CHARACTERISTICS (continued) (V

and VC = 12 V, (Note 2), R

CC

= 10 k, CT = 820 pF, for typical values TA =

ref

25°C, for min/max values TA = −25° to +85°C (Note 3), unless otherwise noted.)

Characteristic UnitMaxTypMinSymbol

SOFT−START SECTION (Note 10)

Duty Cycle (R

Duty Cycle (V

= 12 k)

soft−start

soft−start (Pin 11)

= 0.1 V)

D

soft−start 12k

D

soft−start

36

−

−

42

49

0

OVERVOLTAGE SECTION

Protection Threshold Level on V
Propagation Delay (V
Protection Level on V

> 2.58 V to V

OVP

CC

OVP

Low) 1.0 − 3.0

out

V

OVP−th

V

CC prot

2.42 2.5 2.58 V

TA = 0° to +70°C 16.1 17 17.9

TA = −25° to +85°C 15.9 − 18.1
Input Resistance −

TA = 0° to +70°C 1.5 2.0 3.0

TA = −25° to +85°C 1.4 − 3.4

FOLDBACK SECTION (Note 9)

Current Sense Voltage Threshold (V
Foldback Input Bias Current (V

foldback (Pin 5)

foldback (Pin 5)

= 0.9 V) V

= 0 V) I

CS−th

foldback−lb

0.86 0.89 0.9 V

−6.0 −2.0 −

STANDBY SECTION

Ratio I

R P Stby/Iref

I

R P Stby/Iref

TA = 0° to +70°C 0.37 0.4 0.43

TA = −25° to +85°C 0.36 − 0.44
Ratio Hysteresis (Vh Required to Return to Normal Operation from

Vh/V

R P Stby

Standby Operation)

TA = 0° to +70°C 1.42 1.5 1.58

TA = −25° to +85°C 1.4 − 1.6
Current Sense Voltage Threshold (V

R P Stby (Pin 12)

= 1.0 V) V

CS−Stby

0.28 0.31 0.34 V

CURRENT SENSE SECTION

Maximum Current Sense Input Threshold

(V

feedback (Pin 14)

= 2.3 V and V

foldback (Pin 6)

= 1.2 V)
Input Bias Current I
Propagation Delay (Current Sense Input to Output at VTH of

V

CS−ib

CS−th

0.96 1.0 1.04 V

−10 −2.0 −

− − 120 200 ns

MOS transistor = 3.0 V)

TOTAL DEVICE

Power Supply Current I

CC

Startup (VCC = 13 V with VCC Increasing) − 0.3 0.45
Operating TA = −25° to +85°C (Note 2) 13 17 20

Power Supply Zener Voltage (ICC = 25 mA) V

Z

18.5 − − V

Thermal Shutdown − − 155 − °C

2. Adjust VCC above the startup threshold before setting to 12 V.

3. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible.

4. VC must be greater than 5.0 V.

5. Standby is disabled for V

6. If not used, Synchronization input must be connected to Ground.

7. Synchronization Pulse Width must be shorter than t

8. This function can be inhibited by connecting Pin 8 to GND. This allows a continuous current mode operation.

< 25 mV typical.

R P Stby

OSC

= 1/f

OSC

.

9. This function can be inhibited by connecting Pin 5 to VCC.

10.The MC44603A can be shut down by connecting the Soft−Start pin (Pin 11) to Ground.

%

s

V

k

A

−

−

A

mA

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5

MC44603A

Demag

Detect

Sync
Input

C

R

Pwr Stby

Feed−

back

Compensation

Foldback

Input

8

9

Negative

0.4 I

Active

Clamp

V

ref

+

65 mV

ref

3.7 V

Q

+

0.7 V

R

F Stby

R

15 16

F Stby

R

S

V

Demag Out

Synchro

+

V

OSC prot

Reference

V

refIref

Block

R

ref

V

ref

UVLO2

V

CC

V

1

+

V

CC

18.0 V

aux

14.5 V/7.5 V
To Power

I

F Stby

Transformer

1.0 V

R

0.8 I

2R

S

V

ref

I

Discharge/2

R

Q

I

refVref

1.0 V

Discharge

0.25
IF

Stby

Current Mirror X2

V

OSC

S

Q

R

Thermal

Shutdown

V

ref

0.2 I

ref

0.4 I

V

ref

ref

2.0 s
Delay

V

ref

5.0 s

V
Out

V

OVP

ref

11.6 k

Delay

2.0 k

+

+

1.6 V

2.5 V

UVLO1

V

2.4 V

5.0 mA
+

CC

9.0 V

1.6 V

C

T

10

T

0.4 I

ref

+

3.6 V

0.4 I

V

refVref

ref

0.6 I

R

Q

S

ref

12

V

CC

1.0 mA

14

+

2.5 V

Error Amplifier

13

5

V

C

2

Output

3

4

GND

V

CC

OVP

6

R

OVP

Current
Sense Input

7

= Sink only

= Positive True Logic

SS/D

11

R

SS

/VM

max

C

SS

This device contains 243 active transistors.

Figure 1. Representative Block Diagram

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6

MC44603A

0

0

2

3

4

5

0

, TIMING RESISTANCE (k )Ω

R

100

ref

CT = 2200 pF

10 k

52

51

50

49

48

CT = 100 pF

VCC = 16 V
TA = 25°C

CT = 500 pF

CT = 1000 pF

f

, Oscillator Frequency (Hz)

OSC

Figure 2. Timing Resistor versus

Oscillator Frequency

10000

100010

, TIMING CAPACITOR (pF)

T

C

3003.0

0.43

0.42

0.41

0.40

R

= 2.0 k

F Stby

R

= 5.0 k

F Stby

R

= 27 k

F Stby

R

= 100 k

F Stby

10 k

f

OSC

100 k100 k 1.0 M1.0 M

, Oscillator Frequency (Hz)

Figure 3. Standby Mode Timing Capacitor

versus Oscillator Frequency

VCC = 16 V
TA = 25°C
R

= 10 k

ref

47

, OSCILLATOR FREQUENCY (kHz)

OSC

f

46

45

44

VCC = 12 V
R

= 10 k

ref

CT = 820 pF

−50 −25 0 25 50 75 100

TA, AMBIENT TEMPERATURE (°C)

Figure 4. Oscillator Frequency

versus Temperature

600

400

200

Current

VCC = 12 V
CL = 2200 pF
TA = 25°C

0

−200

−400

, OUTPUT CURRENT (mA)

−600
O

I

Voltage

−800

−1000

Figure 6. Output Waveform Figure 7. Output Cross Conduction

0.39

= RATIO CHARGE CURRENT/I

REFERENCE CURRENT

ref

/I

0.38

charge

0.37

, OUTPUT DRIVE VOLTAGE (V)

O

V

−10

70

60

50

40

30

20

10

, OUTPUT DRIVE VOLTAGE (V)

O

V

0

70

60

50

40

30

20

10

0

−10

VCC = 12 V
R

= 10 k

ref

CT = 820 pF

−50 −25 0 25 50 75 100

TA, AMBIENT TEMPERATURE (°C)

Figure 5. Ratio Charge Current/Reference

Current versus Temperature

VCC = 12 V
CL = 2200 pF
TA = 25°C

Current

V

O

Voltage

I

CC

1.0 s/Div1.0 s/Div

3

2

1

0

−1

−

−

−

−

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