Datasheet IP3842D, IP3842AN-200, IP3842AN, IP3842AD-8, IP3842AD-14 Datasheet (Semelab Plc)

V

CC

Supply Voltage (low impedance source)

(ICC< 30mA)

I

O

Output Current Output Energy (capacitive load) Analog Inputs (pins 2 and 3) Error Amp Output Sink Current

P

D

Power Dissipation T

amb

= 25°C J, N Packages

Derate @ T

amb

> 50°C

P

D

Power Dissipation T

case

= 25°C D Package

Derate @ T

amb

> 50°C

P

D

Power Dissipation T

case

= 25°C J, N Packages

Derate @ T

case

> 25°C

T

STG

Storage Temperature Range

T

L

Lead Temperature (soldering, 10 seconds)

+30V

Self limiting

±1A

5µJ

–0.3V to +V

CC

10mA

1W

10mW/°C

725mW

7.25mW/°C 2W

16mW/°C

–65 to 150°C

+300°C

TOP VIEW

J Package – 8 Pin Ceramic DIP

N Package – 8 Pin Plastic DIP

D-8 Package – 8 Pin Plastic (150) SOIC

1

2

3

4

8

7

6

5

COMP

V

REF

GROUND

OUTPUT

RT/C

T

V

CC

I

SENSE

V

FB

TOP VIEW

D-14 Package – 14 Pin Plastic (150) SOIC

COMP

V

REF

GROUND

OUTPUT

1

2

3

4

POWER GROUND

5

6

7

14

13

12

11

10

9

8

N/C

R

T/CT

I

SENSE

N/C

N/C N/C

V

CC

V

FB

V

C

ABSOLUTE MAXIMUM RATINGS (T

case

= 25°C unless otherwise stated)

LAB

SEME

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Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

CURRENT MODE

REGULATING

PULSE WIDTH

MODULATORS

FEATURES

• Guaranteed ±1% reference voltage tolerance

• Accurate oscillator discharge current

• Guaranteed ±10% frequency tolerance

• Low start–up current (<500 mA)

• Under voltage lockout with hysteresis

• Output state completely defined for all supply and input conditions

• Interchangeable with IP and UC1842/3 series for improved operation

• 500kHz Oscillator operation

Part J–Pack N–Pack D–8 D–14 Temp. Number 8 Pin 8 Pin 8 Pin 14 Pin Range

IP1842A ✔ -55 to +125°C IP2842A ✔✔✔✔-25 to +85°C IP3842A ✔✔✔✔0 to +70°C IP1843A ✔ -55 to +125°C IP2843A ✔✔✔✔-25 to +85°C IP3843A ✔✔✔✔0 to +70°C

Order Information

Note:

To order, add the package identifier to the part number.

eg. IP1842AD–14

IP3843AJ

* 1844A and 1845A series only. Values in brackets are for IP1845 series.

3.6V

ERROR

AMP

OSCILLATOR

2R

R

1V

R

S

PWM

LATCH

CURRENT SENSE COMPARATOR

16V

(8.4V)

6V

(0.5V) 2.5V

UNDER–VOLTAGE

LOCKOUT

ENABLE

REFERENCE REGULATOR

5V

INTERNAL

BIAS

34V

REG

R

S

V STATUS

LATCH

REF

PIN NUMBERS 1st Number 2nd Number

– N, J and 8 Pin D Packag es – 14 Pin D Package.

C

OMP

G

ND

V

CC

I

SENSE

V

FB

/CR

TT

OUTPUT

POWER GROUND

V

REF

V

C

3/5

5/9

7/12

2/3

1/1

4/7 6/10

7/11

5/8

8/14

TOGGLE

FLIP

FLOP *

T

Q

LAB

SEME

IP1842A SERIES IP1843A SERIES

Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

V

CC

Supply Voltage

1

I

O

Output Current Analog Inputs (pins 2 and 3) Error Amp Output Sink Current

IP1842A , IP1843A

Operating Ambient Temperature Range IP2842A , IP2843A

IP3842A , IP3843A

≤ 30V

0 to ±200mA

–0.3V to 3V

0 to 2mA

–55 to 125°C –25 to 85°C

0 to 70°C

Notes:

1. Lower limit set by under voltage lockout specification.

DESCRIPTION

The IP1842A/IP1843A series of switching regulator control circuits contain all the functions necessary to implement off-line, current mode switching regulators, using a minimum number of external parts. Functions included are voltage reference, error amplifier, current sense comparator, oscillator, totem-pole output driver and under-voltage lockout circuitry.

Although pin compatible with the standard IP1842/3 parts these devices offer improved performance in several areas. They also offer tighter specification and improved performance over the IP and UC1842/3 series, whilst retaining complete compatibility.

BLOCK DIAGRAM

RECOMMENDED OPERATING CONDITIONS

NOTES

1. Test Conditions unless otherwise stated: V

CC

= 15V* , RT= 10kΩ , CT= 3.3nF , f = 52kHz.

*Adjust V

CC

above start threshold before setting at required level.

LAB

SEME

IP1842A SERIES IP1843A SERIES

Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

4.90 5.00 5.10 620 625

0.2 0.4

4.82 5.18

50

525

30 80 160

47 52 57

0.2 1 5

1.7

7.8 8.3 8.8 79

2.42 2.50 2.58 –0.3 –2

65 90

0.7 1 60 70

26

–0.5 –0.8

4.6 6

0.7 1.1

4.95 5.00 5.05 620 625

0.2 0.4

4.90 5.10

50

525

30 80 160

47 52 57

0.2 1 5

1.7

7.8 8.3 8.8 79

2.45 2.50 2.55 –0.3 –1

65 90

0.7 1 60 70

26

–0.5 –0.8

4.6 6

0.7 1.1

IP1842A , IP1843A IP3842A IP2842A , IP2843A IP3843A

Parameter Test Conditions

1

Min. Typ. Max. Min. Typ. Max. Units

Output Voltage Input Regulation Output Regulation

Temperature Stability

Total Output Variation Output Noise Voltage Long Term Stability Output Short Circuit Current

Frequency Voltage Stability Temperature Stability Amplitude

Discharge Current

Input Voltage Input Bias Current Open Loop Voltage Gain Unity Gain Bandwidth Supply Voltage Rejection Output Sink Current Output Source Current V

OUT

High

V

OUT

Low

I

O

= 1mA TJ= 25°C

V

CC

= 12V to 25V

I

O

= 1mA to 20mA

Line, Load, Temp f = 10Hz to 10kHz T

J

= 25°C

T

J

= 125°C @ 1000Hrs

V

REF

= 0

T

J

= 25°C

V

CC

= 12V to 25V

∆T

A

= Min to Max

V

PIN4

Peak to Peak

T

J

= 25°C

∆T

A

= Min to Max

V

PIN1

= 2.5V

V

O

= 2V to 4V

V

CC

= 12V to 25V

V

PIN2

= 2.7V V

PIN1

= 1.1V

V

PIN2

= 2.3V V

PIN1

= 5V

V

PIN2

= 2.3V RL= 15kΩ

V

PIN2

= 2.7V RL= 15kΩ

V

mV

°C

V

µV

mV mA

kHz

% %

V

mA

V

µA dB

MHz

dB

mA

V

ELECTRICAL CHARACTERISTICS (Over Full Operating Temperature Range unless otherwise stated)

REFERENCE SECTION

OSCILLATOR SECTION

ERROR AMP SECTION

All specifications apply over the full operating temperature range unless otherwise stated.

(See Ordering Information for further details).

IP1842A , IP1843A IP3842A IP2842A , IP2843A IP3843A

Parameter Test Conditions

1

Min. Typ. Max. Min. Typ. Max. Units

2.85 3 3.15

0.9 1 1.1 60 70

–2 –10

150 300

0.1 0.4

1.5 2.2 13 13.5 12 13.5

50 150 50 150

0.7 1.1

14.5 16 17.5

7.8 8.4 9

8.5 10 11.5 7 7.6 8.2

0.3 0.5 11 15 14 17

30 34 40

95 97 100

0

2.85 3 3.15

0.9 1 1.1 60 70

–2 –10

150 300

0.1 0.4

1.5 2.2 13 13.5 12 13.5

50 150 50 150

0.7 1.1

15 16 17

7.8 8.4 9 91011 7 7.6 8.2

0.3 0.5 11 15 14 17

30 34 40

95 97 100

0

Gain Maximum Input Signal Supply Voltage Rejection Input Bias Current Delay to Output

Output Low Level

Output High Level

Rise Time Fall Time UVLO Saturation

Upper Threshold (V

CC

) Lower Threshold (V

CC

)

Start–up Current Operating Supply Current V

CC

Zener Voltage

Maximum Duty Cycle Minimum Duty Cycle

See Notes 2,3 V

PIN1

= 5V (Note 2)

V

C

= 12V to 25V

I

SINK

= 20mA

I

SINK

= 200mA

I

SOURCE

= 20mA

I

SOURCE

= 200mA

C

L

= 1nF

C

L

= 1nF

V

CC

= 6V IL= 1mA

IP1842A Series IP1843A Series IP1842A Series IP1843A Series

V

PIN2

= 0V IP1842A Series

V

PIN3

= 0V IP1843A Series

I

CC

= 25mA

V/V

V dB µA

ns

V

ns

V

mA mA

V

%

NOTES

LAB

SEME

IP1842A SERIES IP1843A SERIES

Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

ELECTRICAL CHARACTERISTICS (Over Full Operating Temperature Range unless otherwise stated)

CURRENT SENSE SECTION

OUTPUT SECTION

UNDER–VOLTAGE LOCKOUT SECTION

TOTAL STANDBY CURRENT

PWM SECTION

1. Test Conditions unless otherwise stated: V

CC

= 15V* , RT= 10kΩ , CT= 3.3nF , f = 52kHz.

*Adjust V

CC

above start threshold before setting at

required level.

All specifications apply over the full operating temperature range unless otherwise stated. (See Ordering Information for further details).

2. Parameter measured at trip point of latch with V

PIN2

= 0V

3. Gain defined as:

∆V

PIN1

A =

∆V

PIN3

0 ≤ V

PIN3

≤ 0.8

tc≈ 0.55 RTC

T

td≈ RTC

T

Rn

1

Resultant frequency f =

(t

c

+ td)

For R

T

> 5kΩ,

1.8

Resultant frequency f ≈

(R

TCT

)

LAB

SEME

IP1842A SERIES IP1843A SERIES

Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

Open–Loop Laboratory Test Fixture

APPLICATIONS INFORMATION

Oscillator timing capacitor CTis charged by V

REF

through RTand discharged by an internal current source. During the discharge time, the internal clock signal blanks the output to the low state. Selection of R

T

and

C

T

therefore determines both oscillator frequency and maximum duty cycle. Charge and discharge times are determined by the formulae:

High peak current associated with capacitive loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close to pin 5 in a single point ground. The transistor and 5K potentiometer are used to sample the oscillator wave form and apply an adjustable ramp to pin 3.

0.1

µ

F

1k

Ω

1kW

1k

Ω

ERROR AMP

ADJUST

4.7k

Ω

5k

Ω

ADJUST

4.7k

Ω

100k

Ω

2N2222

I

SENSE

R

T

C

T

0.1

µ

F

V

REF

V

CC

OUTPUT

GROUND

1

2

45

7

8

36

I

SENSE

V

REF

V

CC

O/P

GND

COMP

V

FB

RT/C

T

Oscillator Waveforms and Maximum Duty Cycle

8

4

5

GND

R

T

C

T

REF

V

R

TCT

PIN4

V (V for 14 pin D package)

PIN7

INTERNAL CLOCK

OUTPUT – Max. Duty Cycle

PIN6

V (V for 14 pin D package)

PIN10

PIN4

V (V for 14 pin D package)

PIN7

OUTPUT – Max. Duty Cycle

PIN6

V (V for 14 pin D package)

PIN10

LARGE C

T

SMALL R

T

LARGE R

T

SMALL C

T

.0063 RT– 2.3

.0063 – 4

( )

LAB

SEME

IP1842A SERIES IP1843A SERIES

Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612.

Prelim. 2/95

.01 .0 2 .04 .07 .1 .2 .4 .7 1.0

4

3

2

1

0

60

40

20

0

100

80

10 1k100 10k 10M100k 1M

.05 .5.03 .3

OUTPUT CURRENT, SOURCE / SINK (A) FREQUENCY (Hz)

SATURATION VOLTAGE (V)

VOLTAGE GAIN (dB)

OUTPUT SATURATION CHARACTERISTICS

ERROR AMPLIFIER OPEN-LOOP

FREQUENCY RESPONSE

V = 15V

CC

T = 25˚C

A

V

f

SOURCE SAT V - )CCV

OH

SINK SAT (V )

OL

(

A

T = –55˚C

–45

–90

–135

–180

0

PHASE (˚)

TYPICAL PERFORMANCE CHARACTERISTICS