Datasheet CS3524AGNWR16, CS3524AGNW16, CS3524AGN16 Datasheet (Cherry Semiconductor)

1

Features

V

IN

SYNC

C

T

COMP

I

SENSE

+

V

OUT

A

R

T

V

OUT

B

E

B

Gnd

EA-

EA+

I

SENSE

-

SHUTDOWN

E

A

V

REF

-

+

+

-

COMP

EA

CL

5V Reference

Regulator

Flip

Flop

PWM
Latch

OSC

UV

Sense

Power to

Internal

Circuitry

T

R

S

CLOCK

S

RAMP

V

IN

V

IN

200mV

1kΩ

10kΩ

■

Precision Reference
Internally Trimmed to ±1%

■

Current Limit

■ Undervoltage Lockout

■ Start-up Supply Current

< 4mA

■ Output to 200mA

■ 60V Output Capability

■ Wide Common-mode

Input Range for Error and
Current Limit Amplifiers

■ PWM Latch Insures Single

Pulse per Period

■ Double Pulse Suppression

■ 200ns Shutdown

■ Guaranteed Frequency

■ Thermal Shutdown

Package Options

16 Lead PDIP & SO Wide

CS3524A

Voltage Mode PWM Control Circuit

with 200mA Output Drivers

16

15

14

13

12

11

11

10

9

1

2

3

4

5

6

7

8

EA-

EA

+

SYNC

I

SENSE

+

I

SENSE

-

R

T

C

T

Gnd

V

REF

V

IN

E

B

V

OUT

B

V

OUT

A

E

A

SHUTDOWN
COMP

CS3524A

Description

Block Diagram

The CS3524A PWM control circuit
retains the same versatile architecture
of the industry standard CS3524
(SG3524) while adding substantial
improvements.

The CS3524 is pin-compatible with
“non-A” versions, and in most applica­tions can be directly interchanged. The
CS3524A, however, eliminates many of
the design restrictions which had pre­viously required additional external
circuitry.

The CS3524A includes a precision 5V
reference trimmed to ±1% accuracy
(eliminating the need for potentiometer
adjustments), an error amplifier with
an output voltage swing extending to
5V, and a current sense amplifier use­ful in either the ground or power sup­ply output lines. The uncommitted
60V, 200mA NPN output pair greatly
enhances the output drive capability.

The CS3524A features an undervoltage
lockout circuit which disables all inter­nal circuitry (except the reference) until
the input voltage has risen to 8V. This
holds standby current low until turn­on, and greatly simplifies the design of
low power, off-line supplies. The turn­on circuit has approximately 600mV of
hysteresis for jitter free activation.

Other improvements include a PWM
latch that insures freedom from multi­ple pulsing within a period, even in
noisy environments; logic to eliminate
double pulsing on a single output, a
200ns external shutdown capability,
and automatic thermal protection from
excessive chip temperature. The oscil­lator circuit is usable to 500kHz and is
easier to synchronize with an external
clock pulse.

A Company

®

Rev. 10/28/96

Cherry Semiconductor Corporation

2000 South County Trail, East Greenwich, RI 02818

Tel: [phone] Fax: [phone]

Email: [e-mail]

Web Site: www.cherry-semi.com

2

Electrical Characteristics: 0˚C ≤ T

A

≤ +70˚C for the CS3524A; VIN= VCC= 20V; unless otherwise stated.

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Absolute Maximum Ratings

Supply Voltage (VIN).................................................................................................................................................................40V

Collector Supply Voltage (VCC) ...............................................................................................................................................60V

Output Current (Each Output)...........................................................................................................................................200mA

Reference Output Current.....................................................................................................................................................50mA

Oscillator Charging Current ..................................................................................................................................................5mA

Power Dissipation at TA=25˚C.........................................................................................................................................1000mW

Power Dissipation at TJ=+25˚C........................................................................................................................................2000mW

Derate for Case Temperature above +25˚C........................................................................................................16mW/˚C

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

Lead Temperature Soldering: Wave Solder (through hole styles only)..........................................10 sec. max, 260°C peak

Reflow (SMD styles only) ......................................................................................60 sec. max above 183°C, 230°C peak

CS3524A

■ Turn-on Characteristics

Input Voltage Operating range after Turn-on 8 40 V
Turn-on Threshold 5.5 7.5 8.5 V
Turn-on Current VINTurn-on - 100mV 2.5 4.0 mA
Operating Current VIN= 8 to 40V 5 10 mA
Turn-on Hysteresis* 0.6 V

■ Reference Section

Output Voltage TA= 25˚C 4.90 5.00 5.20 V
Line Regulation VIN= 10 to 40V 10 30 mV
Load Regulation IL= 0 to 20mA 20 50 mA
Temperature Stability* Over Operating Range 20 50 mV
Short Circuit Current V

REF

= 0, TA= 25˚C 80 100 mA
Output Noise Voltage* 10Hz ≤ f ≤ 10kHz, TA= 25˚C 40 µVrms
Long Term Stability* TA= 125˚C; 1000 Hrs. 20 50 mV

■ Oscillator Section (Unless otherwise specified, R

T

= 2700Ω, CT= 0.01µF)

Initial Accuracy TA= 25˚C394347kHz
Temperature Stability* Over Operating Temperature Range 1 2 %
Minimum Frequency RT= 150kΩ, CT= 0.1µF 120 Hz
Maximum Frequency RT= 2.0kΩ, CT= 470pF 500 kHz
Output Amplitude* TA= 25˚C 3.5 V
Output Pulse Width* TA= 25˚C 0.5 µs
Ramp Peak 3.3 3.5 3.7 V
Ramp Valley 0.7 0.9 1.0 V

■ Error Amplifier Section (Unless otherwise specified, V

CM

= 2.5V)

Input Offset Voltage 2 10 mV
Input Bias Current 1 10 µA
Input Offset Current 0.5 1.0 µA
Common Mode

Rejection Ratio VCM= 1.5 to 5.5V 60 75 dB
Power Supply Rejection Ratio VIN= 10 to 40V 50 60 dB
Output Swing Minimum Total Range 0.5 5.0 V

* These parameters are guaranteed by design but not 100% tested in production.

3

CS3524A

Electrical Characteristics: continued

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Typical Performance Characteristics

80

60

40

20

0

100 1k 10k 100k 1M

FREQUENCY (Hz)

RF = ∞

OPEN VOLTAGE GAIN (dB)

RF = 1MΩ
RF = 300kΩ

RF = 100kΩ
RF = 30kΩ

VIN = 20V
TA = 25˚C

RF is impedance to ground.
Values below 30kΩ will begin
to limit the maximum
duty-cycle.

50

40

30

20

10

0

12345

INPUT VOLTAGE V

IN

DUTY-CYCLE (ONE OUTPUT) - %

VIN = 20V
R

T

= 2700Ω

TA = 25˚C

0

CT = 10 µF

CT = 1 µF

Note: Duty-Cycle is
percent of two
clock periods that
one output conducts

Duty Cycle vs. Input Voltage

Error Amplifier Voltage Gain vs. Frequency Over RF

■ Error Amplifier Section (Unless otherwise specified, V

CM

= 2.5V): continued

Open Loop Voltage Gain ∆

V

OUT

= 1 to 4V, RL ≥ 10 MΩ 60 80 dB

Gain-Bandwidth* TA= 25˚C, AV= 0dB 3 MHz

■ Current Limit Amplifier (Unless otherwise specified, V

SENSE

= VO)

Input Offset Voltage TA= 25˚C, EA Set for Max. Output 180 200 220 mV
Input Offset Voltage Over Operating Temperature Range 170 230 mV
Input Bias Current -1 -10 µA
Common Mode

Rejection Ratio V

SENSE

= 0 to 15V 50 60 dB
Power Supply Rejection Ratio VIN= 10 to 40V 50 60 dB
Output Swing Minimum Total Range 0.5 5.0 V
Open Loop Voltage Gain ∆

V

OUT

= 1 to 4V, RL≥ 10MΩ 70 80 dB

Delay Time* ∆V

IN

= 300mV 300 ns

■ Output Section (Each Output)

Collector Emitter Voltage I

C

= 100µA 60 80 V
Collector Leakage Current VCE= 50V 0.1 20.0 µA
Saturation IC= 20mA 0.2 0.4 V

IC= 200mA 1.0 2.2 V
Emitter Output Voltage IE= 50mA 17 18 V
Rise Time* TA= 25˚C, R = 2kΩ 200 ns
Fall Time* TA= 25˚C, R = 2kΩ 100 ns
Comparator Delay* TA= 25˚C, V

COMP

to V

OUT

300 ns

Shutdown Delay* TA= 25˚C, V

SHUT

to V

OUT

200 ns
Shutdown Threshold TA= 25˚C, RC= 2kΩ 0.5 0.7 1.0 V
Thermal Shutdown* 165 ˚C

* These parameters are guaranteed by design but not 100% tested in production.

4

CS3524A

Typical Performance Characteristics continued

1M

2 5 10 20 100

TIMING RESISTOR - RT (kΩ)

OSCILLATOR FREQUENCY (Hz)

1 50

100k

10k

1k

100

VIN = 20V
T

A

= 25˚C

C

T

= 1.0nf

C

T

= 3.0nf

C

T

= 10nf

C

T

= 30nf

C

T

= 100nf

1.15

RTC

T

f≈

10

2 5 10 20 100

TIMING CAPACITOR - CT (nf)

OUTPUT DEAD TIME (µs)

1 50

5.0

2.0

1.0

0.5

0.2

0.1

VIN = 20V
RT = 2700Ω
TA = 25˚C

Note: Dead time = osc output pulse
width plus output delay

Output Dead Time vs. Timing Capacitor Value

Oscillator Frequency vs. Timing Components Resistor

Over Timing Capacitance

6

1234

DELAY TIME (µs)

OUTPUT (V)

INPUT at I

SENSE+

0

5
4
3
2
1
0

0.2

0.1

0.0

INTPUT (V)

VIN 20V TA 25˚C
EA+ = V

REF

I

SENSE–

= Gnd

OUTPUT at COMP

5%

Overdrive

10%
20%
50%

20
15
10

5
0

1.0

0.5

0.0

0123

DELAY TIME (µs)

OUTPUT (V)

VIN = 20V
R

L

= 2kΩ

T

A

= 25˚C

INTPUT (V)

OUTPUT at

V

O

A

OR V

O

B

INPUT at

SHUTDOWN

Note: Minimum input pulse width
to latch is 200ns

20
15
10

5
0
5

0

0123

DELAY TIME (µs)

OUTPUT (V)INTPUT (V)

4
3

2
1

VIN = 20V
RL = 2kΩ
TA = 25˚C

OUTPUT at
V

OA

or V

OB

INPUT at V

OB

Note: Minimum input pulse width
to latch is 200ns

Shutdown Delay From PWM Comparator

Turn-Off Delay From Shutdown

Current Limit Amplifier Delay

10

9
8
7
6
5
4
3
2
1
0

01020304050

Note: Outputs off. RT = ∞

SUPPLY VOLTAGE VIN (V)

TA = -55°C

TA = 25°C

TA = 125°C

QUIESCENT CURRENT (mA)

Quiescent Supply Current vs. Supply Voltage Over

Temperature

5

Typical Performance Characteristics continued

5

4

3

2

1

0

50 100 150 200 250

OUTPUT COLLECTOR CURRENT (mA)

V

CE

SAT (V)

TA = 125˚C

0

TA = 25˚C

TA = –55˚C

Output Saturation Voltage vs. Output Current Over

Temperature

I

S

CS3524A

0.1
R

T

C

T

0.1

10kΩ

2kΩ

10kΩ

1kΩ

2kΩ

100kΩ 100kΩ

SHUTDOWN

2kΩ

1W

2kΩ

1W

V

CC

V

IN

SYNC

V

REF

V

OUT

A

V

OUT

B

E

A

E

B

R

T

CTEA+

EA–

COMP

I

SENSE

+

I

SENSE

-

SHUTDOWN

Gnd

Open Loop Test Circuit

Note: The CS3524A should be able to be tested in any 3524 test circuit with two possible exceptions:

1. The higher gain-bandwidth of the current limit amplifier in the CS 3524A may cause oscillations in an uncom­pensated 3524 test circuit.

2. The effect of the shutdown, cannot be seen at the compensation terminal, but must be
observed at the outputs.

CS3524A

Part Number Description

CS3524AGN16 16 Lead PDIP
CS3524AGDW16 16 Lead SO Wide
CS3524AGDWR16 16 Lead SO Wide (tape & reel)

6

Thermal Data 16 Lead 16L

PDIP SO Wide

R

Θ

JC

typ 42 23 ˚C/W

R

Θ

JA

typ 80 105 ˚C/W

D

Lead Count Metric English

Max Min Max Min
16 Lead PDIP 19.69 18.67 .775 .735
16L SO Wide 10.50 10.10 .413 .398

Package Specification

PACKAGE DIMENSIONS IN mm (INCHES)

Ordering Information

PACKAGE THERMAL DATA

Rev. 10/28/96

CS3524A

© 1999 Cherry Semiconductor Corporation

Cherry Semiconductor Corporation reserves the
right to make changes to the specifications without
notice. Please contact Cherry Semiconductor
Corporation for the latest available information.

Plastic DIP (N); 300 mil wide

0.39 (.015)
MIN.

2.54 (.100) BSC

1.77 (.070)

1.14 (.045)

D

Some 8 and 16 lead
packages may have
1/2 lead at the end
of the package.
All specs are the same.

.203 (.008)

.356 (.014)

REF: JEDEC MS-001

3.68 (.145)

2.92 (.115)

8.26 (.325)

7.62 (.300)

7.11 (.280)

6.10 (.240)

.356 (.014)

.558 (.022)

Surface Mount Wide Body (DW); 300 mil wide

1.27 (.050) BSC

7.60 (.299)

7.40 (.291)

10.65 (.419)

10.00 (.394)

D

0.32 (.013)

0.23 (.009)

1.27 (.050)

0.40 (.016)

REF: JEDEC MS-013

2.49 (.098)

2.24 (.088)

0.51 (.020)

0.33 (.013)

2.65 (.104)

2.35 (.093)

0.30 (.012)

0.10 (.004)