UNITRODE UCC15701, UCC15702, UCC25701, UCC25702, UCC35701 Technical data

UCC15701/2

UCC25701/2

UCC35701/2

Advanced Voltage Mode Pulse Width Modulator

DESCRIPTION

The UCC35701/UCC35702 family of pulse width modulators is intended for

isolated switching power supplies using primary side control. They can be

used for both off-line applications and DC/DC converter designs such as in

a distributed power system architecture or as a telecom power source.

The devices feature low startup current, allowing for efficient off-line start

-

ing, yet have sufficient output drive to switch power MOSFETs in excess of

500kHz.

Voltage feed forward compensation is operational over a 5:1 input range

and provides fast and accurate response to input voltage changes over a

4:1 range. An accurate volt-second clamp and maximum duty cycle limit

are also featured.

Fault protection is provided by pulse by pulse current limiting as well as the

ability to latch off after a programmable number of repetitive faults has oc

-

curred.

Two UVLO options are offered. UCC35701 family has turn-on and turn-off

thresholds of 13V/9V and UCC35702 family has thresholds of 9.6V/8.8V.

The UCC35701/2 and the UCC25701/2 are offered in the 14 pin SOIC (D),

14 pin PDIP (N) or in 14 pin TSSOP (PW) packages. The UCC15701/2 is

offered in the 14 pin CDIP (J) package.

3VDD

12 VREF

8FB

4OUT

2ILIM

5PGND

C3

1 COUNT

CF

14 SS

CS

11 SYNC

9 VSCLAMP

VREF

10 CT

CT

7RT

6

VFF

13GND

V

IN

SUPPLY

V

IN

RETURN

RGND

R10

RCS

R8

R7

R6

C2

R8

R

F

R5

R4

R3

R2

R1

V

OUT

UCC35701

C1

C4

C6

R12

C6

C5

R11

R13

C7

R14

V

OUT

R15

TYPICAL APPLICATION DIAGRAM

SLUS293A - JANUARY 2000

FEATURES

•

700kHz Operation

•

Integrated Oscillator/ Voltage Feed

Forward Compensation

•

Accurate Duty Cycle Limit

•

Accurate Volt-second Clamp

•

Optocoupler Interface

•

Fault Counting Shutdown

•

Fault Latch off or Automatic Shutdown

•

Soft Stop Optimized for Synchronous

Rectification

•

1A Peak Gate Drive Output

• 130µA Start-up Current

• 750µA Operating Current

UDG-98005-1

application

INFO

available

查询UCC15701供应商

2

UCC15701/2

UCC25701/2

UCC35701/2

ABSOLUTE MAXIMUM RATINGS

Supply voltage (Supply current limited to 20mA) . . . . . . . . 15V

Supply Current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mA

Input pins ( ILIM,VFF,RT,CT,VSCLAMP,SYNC,SS) . . . . . . 6V

Output Current (OUT) DC. . . . . . . . . . . . . . . . . . . . . +/–180mA

Output Current (OUT) Pulse (0.5ms) . . . . . . . . . . . . . . +/–1.2A

Storage Temperature. . . . . . . . . . . . . . . . . . . –65°C to +150°C

Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C

Lead Temperature (Soldering, 10 sec.) . . . . . . . . . . . . +300°C

Note: All voltages are with respect to GND. Currents are posi

-

tive into the specified terminal. Consult Packaging Section of

the Databook for thermal limitations and considerations of

packages.

VREF

GND

SS

SYNC

CT

FB

VSCLAMP

1

2

3

4

5

6

7

14

13

12

11

10

9

8

ILIM

COUNT

VFF

RT

VDD

OUT

PGND

CONNECTION DIAGRAMS

DIL-14, SOIC-14,TSSOP-14 (TOP VIEW)

N or J, D, PW PACKAGE

ELECTRICAL CHARACTERISTICS: Unless otherwise specified, V

DD

= 11V, RT = 60.4k, C

T

= 330pF, C

REF

=C

VDD

=

0.1 F, V

FF

= 2.0V, and no load on the outputs.

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

UVLO Section

Start Threshold (UCCX5701) 12 13 14 V

(UCCX5702) 8.8 9.6 10.4 V

Stop Threshold (UCCX5701) 8 9 10 V

(UCCX5702) 8.0 8.8 9.6 V

Hysteresis (UCCX5701) 3 4 V

(UCCX5702) 0.3 0.8 V

Supply Current

Start-up Current (UCCX5701) V

DD

= 11V, V

DD

Comparator Off 130 200 µA

(UCCX5702) V

DD

= 8V, V

DD

Comparator Off 120 190 A

I

DD

Active V

DD

Comparator On 0.75 1.5 mA

V

DD

Clamp Voltage (UCCX5701) I

DD

= 10mA 13.5 14.3 15 V

(UCCX5702) I

DD

= 10mA 13 13.8 15 V

V

DD

Clamp – Start Threshold (UCCX5701) 1.3 V

(UCCX5702) 4.2 V

Voltage Reference

V

REF

V

DD

= 10V to 13V, I

VREF

= 0mA to 2mA 4.9 5 5.1 V

Line Regulation V

DD

= 10V to 13V 20 mV

Load Regulation I

VREF

= 0mA to 2mA 2 mV

Short Circuit Current V

REF

= 0V, TJ = 25°C 20 50 mA

T

A

=T

J

UVLO

Option

Package Part Number

–55°C to +125°C

13V / 9V CDIP-14 UCC15701J

9.6V / 8.8V CDIP-14 UCC15702J

–40°C to +85°C

13V / 9V

SOIC-14 UCC25701D

PDIP-14 UCC25701N

TSSOP-14 UCC25701PW

9.6V / 8.8V

SOIC-14 UCC25702D

PDIP-14 UCC25702N

TSSOP-14 UCC25702PW

0°C to +70°C

13V / 9V

SOIC-14 UCC35701D

PDIP-14 UCC35701N

TSSOP-14 UCC35701PW

9.6V / 8.8V

SOIC-14 UCC35702D

PDIP-14 UCC35702N

TSSOP-14 UCC35702PW

The D and PW packages are available taped and reeled. Add

TR suffix to the device type (e.g., UCC35701DTR).

ORDERING INFORMATION

3

UCC15701/2

UCC25701/2

UCC35701/2

ELECTRICAL CHARACTERISTICS:

Unless otherwise specified, V

DD

= 11V, RT = 60.4k, C

T

= 330pF, C

REF

=C

VDD

=

0.1 F, V

FF

= 2.0V, and no load on the outputs.

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Line Sense

Vth High Line Comparator 3.9 4 4.1 V

Vth Low Line Comparator 0.5 0.6 0.7 V

Input Bias Current –100 100 nA

Oscillator Section

Frequency V

FF

= 0.8V to 3.2V 90 100 110 kHz

Frequency V

FF

= 0.6V to 3.4V (Note 1) 90 100 110 kHz

SYNC VIH 2V

SYNC VIL 0.8 V

SYNC Input Current VSYNC = 2.0V 3 10 µA

RT Voltage VFF = 0.4V 0.5 0.6 0.7 V

VFF = 0.8V 0.75 0.8 0.85 V

VFF = 2.0V 1.95 2.0 2.05 V

VFF = 3.2V 3.15 3.2 3.25 V

VFF = 3.6V 3.3 3.4 3.5 V

C

T

Peak Voltage VFF = 0.8V (Note 1) 0.8 V

VFF = 3.2V (Note 1) 3.2 V

C

T

Valley Voltage (Note 1) 0 V

Soft Start/Shutdown/Duty Cycle Control Section

I

SS

Charging Current 10 18 30 A

I

SS

Discharging Current 300 500 750 µA

Saturation V

DD

= 11V, IC Off 25 100 mV

Fault Counter Section

Threshold Voltage VFF = 0.8V to 3.2V 3.8 4 4.2 V

Saturation Voltage VFF = 0.8V to 3.2V 100 mV

Count Charging Current 10 18 30 µA

Current Limit Section

Input Bias Current –100 0 100 nA

Current Limit Threshold 180 200 220 mV

Shutdown Threshold 500 600 700 mV

Pulse Width Modulator Section

FB Pin Input Impedance VFB = 3V 30 50 100 k

Minimum Duty Cycle VFB <= 1V 0 %

Maximum Duty Cycle VFB >= 4.5V, VSCLAMP >= 2.0V 95 99 100 %

PWM Gain VFF = 0.8V 35 50 70 %/V

Volt Second Clamp Section

Maximum Duty Cycle VFF = 0.8V, VSCLAMP = 0.6V 69 74 79 %

Minimum Duty Cycle VFF = 3.2V, VSCLAMP = 0.6V 17 19 21 %

Output Section

VOH I

OUT

= –100mA, (V

DD

–V

OUT

) 0.4 1 V

VOL I

OUT

= 100mA 0.4 1 V

Rise Time C

LOAD

= 1000pF 20 100 ns

Fall Time C

LOAD

= 1000pF 20 100 ns

Note 1: Guaranteed by design. Not 100% tested in production.