Texas Instruments UCC28230PWRG4, UCC28230 Datasheet

FEATURES

DESCRIPTION

APPLICATIONS

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

Advanced PWM Controller for Bus Converters

• Programmable, Load Depended Off Time

Control

The UCC28230, UCC28231 PWM bus controllers are optimized for use in high efficiency, high power

• Frequency Controlled Start Up Allows Small

density, unregulated intermediate bus converters.

Output Inductor, Low Ripple and Constant

Topologies include push-pull, half-bridge and

Current Start with Large Output Capacitor

full-bridge. External drivers, such as the UCC27200

• Two 0.2-A Push-Pull Outputs Provide Matched

120-V high-side/low-side drivers, can be used with

Control Signals D to External Drivers

this controller.

• Two Additional 1- D Outputs for Optimal Use

Low cost, small size and highly efficient solutions are

of Self-Driven or Control Driven Synchronous

provided by innovations such as:

Rectifiers

• Start-up frequency control circuit allowing small

• Unregulated, Fixed Volt-Second or Fixed

output inductor and the ability to start with large

Frequency Modes set by User

intermediate bus capacitor.

• Two, 1.5% Overall Accuracy Reference Voltage

• Load depended off-time control set by user.

Options: 5-V for UCC28230 and 3.3-V for

Additional 1-D control outputs can be used for

UCC28231

primary winding clamping in self-driven output

• Resistor Programmable Switching Frequency

synchronous rectifier applications or as drive signals

up to 1 MHz

for the control-driven synchronous rectifier.

• Cycle-by-Cycle Current Limit Allows Parallel

Cycle-by-cycle current limit prevents overstresses of

Operation with Droop Based Current Sharing

converter. If the over current condition causes less than 80% duty cycle at the output, then after a

• Single External Capacitor sets Soft-Start and

programmed time the controller proceeds into

Over Current Hiccup Mode Parameters with

periodical shutdown and restart hiccup mode.

Restart

The UCC28230 provides 5 V, and the UCC28231

• Severe Short Circuit Hiccup with Restart or

provides 3.3-V precision reference voltages with 1.5%

Latch Off Protection Option by External

overall accuracy and 10-mA output current. This

Resistor

reference voltage can be used to supply

• Input Under Voltage Lock Out

housekeeping circuit and/or microcontroller. The

• Thermal Shutdown

precision reference voltage can also be used for accurate setting of system parameters.

• Thermally Enhanced 3 mm × 2 mm SON-12

and TSSOP-14 Package Options

Other features include under-voltage lockout, thermal shut down, programmable soft start, over-current hiccup mode and short circuit protection with internal restart by default that can be set into latch-off mode

• Intermediate Bus Isolated Converters

by an external resistor.

• DC-to-DC Transformers

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

TYPICAL APPLICATION DIAGRAMS

Vin

36 Vto60V

Vout

7 Vto12 V

400W

Vbias

Vcc=5 Vor3.3V

Interface

with

System

UCC27200UCC27200

Bias Power Supply

Vbias

Housekeeping

Micro

Controller

GND

O1_D

VREF

5V/3.3V

LDO

UVLO

Comp.

6.3Vrise

5.7 Vfall

Vin

Thermal Shutdown

O2_DIN

O2_D

O1_DIN

SoftStart

HiccupCurrent

LimitCircuit

Logic Block

Reference Generator

ShortCircuit

Shutdown

Oscillator

StartUp

Frequency

Control

Off Time

Control Circuit

Cycle-by

CycleCurrent

Limit

CLK

OST

Vin

36Vto60V

Vout

7Vto12V

200W

Vbias

Houskeeping

Micro-

Controller

Vcc=5Vor3.3V

Interface

with

System

UCC27200

Bias Power Supply

Vbias

UCC28230/1

INA

GND

INB

UCC27324

OUTA

OUTB

Vbias

GND

O1_D

VREF

5V/3.3V

LDO

UVLO

Comp.

6.3Vrise

5.7 Vfall

Vin

Thermal Shutdown

O2_DIN

O2_D

O1_DIN

SoftStart

HiccupCurrent

LimitCircuit

Logic Block

Reference Generator

ShortCircuit

Shutdown

Oscillator

StartUp

Frequency

Control

Off Time

Control

Circuit

Cycle -by -

CycleCurrent

Limit

CLK

OST

UCC28230 UCC28231

SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008 ...................................................................................................................................................

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Figure 1. Full-Bridge Bus Converter

Figure 2. Half-Bridge Bus Converter with Control-Driven Synchronous Rectifier

Product Folder Link(s): UCC28230 UCC28231

PINOUT CONFIGURATION

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

ORDERING INFORMATION

(1) (2)

TEMPERATURE RANGE,

REFERENCE VOLTAGE PACKAGE TAPE and REEL QTY PART NUMBER

TA= T

5 V .250 UCC28230DRNT 5 V 3000 UCC28230DRNR

Plastic 12-pin SON (DRN)

3.3 V 250 UCC28231DRNT

3.3 V 3000 UCC28231DRNR

– 55 ° C to +125 ° C

5 V 250 UCC28230PW 5 V 2000 UCC28230PWR

Plastic 14-pin TSSOP (PW)

3.3 V 250 UCC28231PW

3.3 V 2000 UCC28231PWR

(1) The 12-pin SON (DRN) and 14-pin TSSOP packages use Pb-Free lead finish of Pd-Ni-Au which is compatible with MSL level 1 at

255-260 ° C peak reflow temperature to be compatible with either lead free or Sn/Pb soldering operations.

(2) The pad underneath the center of the IC is a thermal substrate. The PCB “ thermal land ” design for this exposed die pad should include

thermal vias that drop down and connect to one or more buried copper plane(s). This combination of vias for vertical heat escape and buried planes for heat spreading allows the DRN to achieve its full thermal potential. This pad is also internally connected to GND pin.

Product Folder Link(s): UCC28230 UCC28231

ABSOLUTE MAXIMUM RATINGS

DISSIPATION RATINGS

(1)

RECOMMENDED OPERATING CONDITIONS

UCC28230 UCC28231

SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008 ...................................................................................................................................................

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over operating free-air temperature range

(1) (2)

(unless otherwise noted)

PARAMETER VALUE UNIT

(3)

Input supply voltage range – 0.3 to 20.0 O1_D, O2_D, O1_DIN, O2_DIN – 0.3 to V

+0.3

Inputs voltages on OS, CS, SS, RT, OST – 0.3 to 6.3

Output voltage on VREF – 0.3 to 5.6

HBM 2k

ESD rating

CDM 500

Continuous total power dissipation See Dissipation Rating Table

Operating virtual junction temperature range – 55 to +150

Operating ambient temperature range – 55 to +125

° C

stg

Storage Temperature – 65 to +150 Lead Temperature (Soldering, 10 sec.) PW Package +300

(1) 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 under recommended operating

conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. (2) These devices are sensitive to electrostatic discharge; follow proper device handling procedures. (3) All voltages are with respect to GND unless otherwise noted. Currents are positive into, negative out of the specified terminal. See

Packaging Section of the datasheet for thermal limitations and considerations of packages.

θJC( ° C/W) θJA( ° C/W) θJB( ° C/W)

θJP( ° C/W)

BOARD PACKAGE JUNCTION TO JUNCTION TO JUNCTION TO

JUNCTION TO PAD

CASE AMBIENT BOARD

High-K

(2)

DRN 70.66 15 37.66

PW 2.71 97.65 2.07

(1) These thermal data are taken at standard JEDEC test conditions and are useful for the thermal performance comparison of different

packages. The cooling condition and thermal impedance R

θ JA

of practical design is specific.

(2) The JEDEC test board JESD51-5 with direct thermal pad attach, 3-inch × 3-inch, 4-layer with 1-oz internal power and ground planes and

2-oz top and bottom trace layers (preliminary data based on modeling)

MIN NOM MAX UNIT

Supply voltage range 7 12 17 V Operating junction temperature range – 55 125 ° C

Product Folder Link(s): UCC28230 UCC28231

ELECTRICAL CHARACTERISTICS

(1)

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

= 12V, 1- µ F capacitor from V

and VREF to GND, TA= TJ= – 55 ° C to 125 ° C, RT = 49.9 k Ω connected to 4.4V supply to

set Fsw = 100 kHz (unless otherwise noted).

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Supply Currents

DD(off)

Startup current VDD= 5.2 V 150 200 µ A

Operating supply current 1.5 2.5 mA

Under Voltage Lockout

Start threshold 5.9 6.3 6.9 Minimum operating voltage after start 5.3 5.7 6.2 V Hysteresis 0.55 0.6 0.75

Soft Start (SS PIN, Figure 41 , Figure 44 )

Charge current VSS= 0 V – 30 – 25 – 20 µ A

SS_STD

Shutdown/restart/reset threshold 0.3 0.55 0.68

SS_FP

Soft-start first pulse threshold 0.68 0.85 1.1

SS_PU

Pull up threshold 3.3 3.5 3.8

SS_CL

Clamp voltage 4.3 4.5 4.8

Off-Time Programming (Figure 33 )

OFF5

Off time between O1_D and O2_D UCC28230 32 40 50

OFF3

Off time between O1_D and O2_D UCC28231 30 40 53

OS = 8.45 k Ω , CS = 0.3 V, OST = 1 V

Dead time between O1_D, O1_DIN and O2_D, O2_DIN 10 16

Δ T

OFF

Off time matching 2

OFFR5

Off time between O1_D and O2_D UCC28230 32 40 50

OFFR3

Off time between O1_D and O2_D UCC28231 30 40 53

OS = 8.45 k Ω , CS = 0 V, OST = VREF

DTREF

Dead time between O1_D, O1_DIN and O2_D, O2_DIN 10 16

Δ T

OFFR

Off time matching 2

HYST

Hysteresis current source 10 µ A

OS = 8.45 k Ω , OST = 1 V, CS = CS

– 0.03

OFFMAX

Maximum off time at low CS 165 235 ns

Switching Frequency at O1_D and O2_D Outputs

SWNOM

Nominal frequency VSS= 4 V 92 100 108

kHz

SWMAX

Maximum frequency VSS= 1.8 V 425 550 675

VREF Output Voltage

REF5

UCC28230 4.925 5 5.075

0 ≤ IR ≤ 10 mA; VDD= from 7 V to 17 V,

VREF total output range V

– 55 ° C ≤ TJ≤ 125 ° C

REF3

UCC28231 3.25 3.3 3.35

SCC

Short circuit current VREF = 0 V – 35 – 25 – 12 mA

(1) Typical values for TA= 25 ° C

Product Folder Link(s): UCC28230 UCC28231

UCC28230 UCC28231

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ELECTRICAL CHARACTERISTICS (continued)

= 12V, 1- µ F capacitor from V

and VREF to GND, TA= TJ= – 55 ° C to 125 ° C, RT = 49.9 k Ω connected to 4.4V supply to

set Fsw = 100 kHz (unless otherwise noted).

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Current Sense, Cycle-by-Cycle Current Limit With Hiccup, Short Circuit Protection With Latch Off

CS_LIM

CS pin cycle-by-cycle threshold 0.48 0.5 0.515 V

Input pulse at CS from 0.3 V to 0.6 V with

CS to O1_D and O2_D propagation delay 100

0.03 V/ns slew rate ns

Input pulse at CS from 0.3 V to 0.6 V with

Leading edge blanking time by internal filter 50

0.03 V/ns slew rate

Discharge current to set cycle-by-cycle current limit duration

CS = 0.6 V, VSS= 4 V 15 20 25 µ A

(Figure 41 ) Hiccup OFF time threshold 3.1 3.4 3.7 V Discharge current to set Hiccup Mode OFF Time

HCC

1.9 2.5 3.1 µ A

(Figure 41 , Figure 44 )

CS_SC

CS pin short circuit protection threshold (Figure 44 ) 0.65 0.7 0.75 V

Outputs O1_D, O2_D, O1_DIN, O2_DIN

Sink/Source peak current

(2)

0.2 A

Rise time C

LOAD

= 100 pF 12 25

Fall time C

LOAD

= 100 pF 10 25

RSRC Output source resistance I

OUT

= 20 mA 10 20 35

Ω

RSINK Output sink resistance I

OUT

= 20 mA 5 15 30

Pins 7 and 9 pulses matching at FSW= 100

Duty cycle matching 35 ns

kHz

Thermal Shutdown

Rising threshold

(3)

150 160 170

Falling threshold

(3)

130 140 150 ° C

Hysteresis 20

(2) Output sink/source peak current value, defined by equation IP= 100 pF × dV/dt where dV/dt is taken from the output rise and fall

switching waveforms. It is not tested in production. Characterization is available upon request.

(3) Thermal shutdown is not tested in production. Characterization is available upon request

Product Folder Link(s): UCC28230 UCC28231

FUNCTIONAL BLOCK DIAGRAMS

GND

O1_D

VREF

5V/3.3V

LDO

UVLO

Comp.

6.3V rise

5.7V fall

Vin

Thermal

Shutdown

O2_DIN

O2_D

O1_DIN

Soft Start &

Hiccup Current

Limit Circuit

Logic

Block

Reference Generator

Short Circuit

Shutdown

Oscillator &

Start Up

Frequency

Control

Off Time

Control Circuit

Cycle-by-

Cycle Current

Limit

CLK

OST

GND

O1_D

VREF

5V/3.3V

LDO

UVLO

Comp.

6.3V rise

5.7V fall

Vin

Thermal

Shutdown

O2_DIN

O2_D

O1_DIN

Soft Start &

Hiccup Current

Limit Circuit

Logic Block

Reference Generator

Short Circuit

Shutdown

Oscillator &

Start Up

Frequency

Control

Off Time

Control

Circuit

Cycle-by-

Cycle Current

Limit

CLK

OST

AGND

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

Figure 3. SON-12 Package

Figure 4. TSSOP-14 Package

Product Folder Link(s): UCC28230 UCC28231

UCC28230 UCC28231

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TERMINAL FUNCTIONS

TERMINAL

I/O FUNCTION

DFN-12 TSSOP-14

NAME

PIN# PIN#

± 1.5% accurate 5 V for UCC28230 and 3.3 V for UCC28231, 10-mA output reference voltage with short circuit protection that can be used for fixed switching frequency setting and/or for

1 1 VREF O

housekeeping microcontroller. Place decoupling capacitor in 1 µ F to 2.2 µ F range from this pin to GND.

Off time control threshold pin uses a resistor divider to set current level as percentage of current

2 2 OST I

limit threshold. Nominal off time T

OFF

and dead time TDTset pin. An external resistor connected between this pin

3 3 OS I

and GND sets the dead time and nominal off time.

4 NC Not connected pin, TSSOP-14 only.

Oscillator timing input pin. The external resistor which is connected between this pin and VINsets

4 5 RT I the oscillator frequency which varies with VIN. Tying the external resistor to VREF sets fixed

frequency operation independent of VIN. Input to adjustable soft-start,and hiccup mode circuit. Place soft-start capacitor from this pin to

5 6 SS I/O GND. The internal charge/discharge current ISSand an external capacitor value set the soft-start

timing, duration of cycle-by-cycle current limit and controller turn-off time for hiccup mode operation.

6 7 CS I Current sensing pin used for cycle-by-cycle current limit, short circuit protection and off time control.

8 AGND Analog ground, TSSOP-14 only. 7 9 GND Ground pin connected to thermal pad. All signals are referenced to this node. 8 10 O2_DIN O 0.2-A sink/source switching output pin to an external driver providing 1-D pulse. 9 11 O2_D O 0.2-A sink/source switching output pin to an external driver providing D pulse.

10 12 O1_DIN O 0.2-A sink/source switching output pin to an external driver providing 1-D pulse. 11 13 O1_D O 0.2-A sink/source switching output pin to an external driver providing D pulse.

Connect this pin to a 7-V to 17-V bias supply. Place a high quality at least 1- µ F ceramic bypass

12 14 VDD I

capacitor from this pin to GND.

Product Folder Link(s): UCC28230 UCC28231

TYPICAL CHARACTERISTICS

Operating Supply Current I

over Temperature at FSW=100kHz

1.40

1.45

1.50

1.55

1.60

-55 -35 -15 5 25 45 65 85 105 125

TJ-tempe rature, °C

DD,

Start-up Current I

DDoff

over Temperature at VDD=5.2V

135

140

145

150

155

160

165

-55 -35 -15 5 25 45 65 85 105 125

TJ-tempera ture, °C

DDo ff,,

µA

Under Voltage Lockout Thresholds

over Temperature

5.3

5.5

5.7

5.9

6.1

6.3

6.5

6.7

-55 -35 -15 5 25 45 65 85 105 125

TJ-temperature, °C

UVLO Thresholds, V

Rising threshold

Falling threshold

Under Voltage Lockout Hysteresis

over Temperature

0.62

0.64

0.66

0.68

0.70

-55 -35 -15 5 25 45 65 85 105 125

TJ-temperature, °C

UVLO Hysteresis, V

Soft Start Shutdown V

SS_STD

and First Pulse V

SS_FP

Thresholds over Temperature

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

-55 -35 -15 5 25 45 65 85 105 125

TJ-te mperature, ° C

SS_STD

, V

SS_FP

, V

Soft Start Shutdown

First Puls e Threshold

Soft Start Pull-up V

SS_PU

and Clamp Voltage V

SS_CL

Thresholds over Temperature

3.00

3.50

4.00

4.50

5.00

-55 -35 -15 5 25 45 65 85 105 125

TJ-te mperature, ° C

SS_PU

, V

SS_CL

, V

Pull-up Threshold

Clamp Voltage

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

Figure 5. Figure 6.

Figure 7. Figure 8.

Figure 9. Figure 10.

Product Folder Link(s): UCC28230 UCC28231

Soft-Start Charge Current I

over Temperature

24.80

24.85

24.90

24.95

25.00

25.05

25.10

25.15

25.20

-55 -35 -15 5 25 45 65 85 105 125

TJ-temperature, °C

Iss, µA

OffTimeMatching ∆T

OFF

overTemperature

1.00

1.50

2.00

2.50

3.00

3.50

4.00

-55 -35 -15 5 25 45 65 85 105 125

TJ-temperature,°C

∆T

OFF

,ns

UCC28230 Off Time T

OFF

and Dead Time T

over Temperature

-55 -35 -15 5 25 45 65 85 105 125

TJ- te mperature, °C

OFF

, T

, ns

Off Time

Dead Time

UCC28231 Off Time T

OFF

and Dead Time T

over T emperature

-55 -35 -15 5 25 45 65 85 105 125

TJ- tempe rature, °C

OFF

, T

, ns

Off Time

Dead Time

Maximum Off Time T

OFFMAX

at Low V

over Temperature

170.00

180.00

190.00

200.00

210.00

220.00

-55 -35 -15 5 25 45 65 85 105 125

TJ- te mperatu re, °C

OFFM AX

, ns

Nominal Switching Frequency F

SWNOM

over Temperature

99.00

99.50

100.00

100.50

101.00

-55 -35 - 15 5 25 45 65 85 105 125

TJ- te mperature, ° C

SWNOM

, kHz

UCC28230 UCC28231

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TYPICAL CHARACTERISTICS (continued)

Figure 11. Figure 12.

Figure 13. Figure 14.

Figure 15. Figure 16.

Product Folder Link(s): UCC28230 UCC28231

Maximum Switching Frequency F

SWMAX

over Temperature

500.00

510.00

520.00

530.00

540.00

550.00

-55 -35 - 15 5 25 45 65 85 105 125

TJ- temperature , °C

FSWMAX , kHz

Cycle-by-Cycle Current Limit Threshold

over Temperature

0.45

0.47

0.49

0.51

0.53

0.55

-55 -35 -15 5 25 45 65 85 105 125

TJ-tempera ture, °C

CS_LIM

, V

UCC28230 Refer ence Voltage at VDD=12V

over Te mperature and Load Curr ent

4.9 75

4.9 85

4.9 95

5.0 05

5.0 15

-55 -3 5 - 15 5 2 5 45 65 8 5 105 125

TJ- te mper ature, °C

REF

, V

Iload=10uA

Iload=1mA Iload=10mA

UCC28231 Refer ence Voltage at VDD=12V

over Te mperature and Load Curr ent

3.2 75

3.2 85

3.2 95

3.3 05

-55 -35 - 15 5 2 5 45 65 85 105 1 25

- te mper ature, °C

REF

, V

Iload=10uA

Iload=1mA Iload=10mA

UCC28230 Refer ence Voltage at I

LOAD

=1mA

over Te mper ature and Supply Voltage V

4.990

4.994

4.998

5.002

5.006

-55 - 35 -15 5 25 45 65 85 105 125

TJ- te mper ature, °C

REF

, V

Vdd=7V

Vdd=12V Vdd=17V

UCC28231 Refer ence Voltage at I

LOAD

=1mA

over Te mperature and Supply Voltage V

3.2 90

3.2 94

3.2 98

3.3 02

3.3 06

-55 -35 -1 5 5 25 45 65 8 5 105 1 25

TJ- te mper ature, °C

REF

, V

Vdd=7V

Vdd=12V Vdd=17V

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

TYPICAL CHARACTERISTICS (continued)

Figure 17. Figure 18.

Figure 19. Figure 20.

Figure 21. Figure 22.

Product Folder Link(s): UCC28230 UCC28231

Current Sense Propogation Delay T

over Temperature

90.00

95.00

100.00

105.00

110.00

115.00

-55 -35 - 15 5 25 45 65 85 105 125

TJ- te mperatu re, °C

, ns

Output Source Resistance R

SRC

and Sink Resistance

SINK

over Temperature

10.0

15.0

20.0

25.0

30.0

-55 -35 -15 5 25 45 65 85 105 125

TJ- te mperatur e, °C

SCR

, R

SINK

, O

Source Resistance

Sink Resist ance

UCC28230 UCC28231

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TYPICAL CHARACTERISTICS (continued)

Figure 23. Figure 24.

Figure 25. O1_D and O2_D Duty Cycle Matching at V

= Figure 26. O1_D and O2_D Duty cycle Matching at V

0.14 V and V

OST

= 1 V 0.0 V and V

OST

= 1 V

Product Folder Link(s): UCC28230 UCC28231

UCC28230 UCC28231

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................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008

TYPICAL CHARACTERISTICS (continued)

Figure 27. Output Waveforms During First Half Switching Cycle at V

= 0.14 V and V

OST

= 1 V

Figure 28. Output Waveforms During Second Half Switching Cycle at V

= 0.14 V and V

OST

= 1 V

Product Folder Link(s): UCC28230 UCC28231

UCC28230 UCC28231

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TYPICAL CHARACTERISTICS (continued)

Figure 29. Output Waveforms During First Half Switching Cycle at V

= 0 V and V

OST

= 1 V

Figure 30. Output Waveforms During Second Half Switching Cycle at V

= 0 V and V

OST

= 1 V

Product Folder Link(s): UCC28230 UCC28231

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