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PTH03060Y

PTH05060Y, PTH12060Y

SLTS222A–MARCH 2004–REVISED OCTOBER 2005

Designing for Very Fast Load Transients

The transient response of the dc/dc converter is characterized using a load transient with a di/dt of 1 A/µs. The

typical voltage deviation for this load transient is given in the data sheet specification table using the optional

value of output capacitance. As the di/dt of a transient is increased, the response of a converter's regulation

circuit ultimately depends on its output capacitor decoupling network. This is an inherent limitation with any dc/dc

converter once the speed of the transient exceeds its bandwidth capability. If the target application specifies a

higher di/dt or lower voltage deviation, the requirement is met with additional output capacitor decoupling. In

these cases, special attention must be paid to the type, value, and ESR of the capacitors selected.

If the transient performance requirements exceed that specified in this data sheet, or the total amount of load

capacitance is above 5500 µF, the selection of output capacitors becomes more important.

Capacitor Characteristics

Quantity

Max Ripple

Capacitor Vendor,

Working

Max ESR

Vendor Number

Value

Current at

Physical Size

Input Output

Type/Series (Style)

Voltage

at 100 kHz

(µF)

85°C (Irms)

(mm)

Bus

Bus

(V)

(Ω)

(mA)

Panasonic, Aluminum

25

560

0.065

1205

12,5 × 15

1

1

EEUFC1E561S

FC (Radial)

25

1000

0.060

1100

12,5 × 13,5

1

1

EEVFK1E102Q

FK (SMD)

35

680

0.060

1100

12,5 × 13,5

1

1

EEVFK1V681Q

United Chemi-Con

LXZ, Aluminum (Radial)

16

330

0.0014

5050

10 × 12,5

2

≤2

16PS330MJ12

PS, Poly-Aluminum (Radial)

16

680

0.068

1050

10 × 16

1

1

LXZ16VB681M10X16LL

PXA, Poly-Aluminum (SMD)

16

330

0.014

5050

10 × 12,2

2

≤2

PXA16VC331MJ12

Nichicon Aluminum

25

560

0.060

1060

12,5 × 15

1

1

UPM1E561MHH6

PM (Radial)

16

680

0.038

1430

10 × 16

1

1

UHD1C681MHR

HD (Radial)

35

560

0.048

1360

16 × 15

1

1

UPM1V561MHH6

Sanyo

TPE, pos-cap (SMD)

10

330

0.025

3000

7,3 L × 5,7 W

≤3

10TPE330M

SEPC, Os-con (Radial)

16

270

0.011

5000

8 × 12

≤1

16SP270M

SVP, Os-con (SMD)

16

330

0.016

4700

11 × 12

2

≤2

16SVP330M

SVPC, Os-con (SMD)

4

1200

0.010

4700

8 × 11,9

≤1

4SVPC1200M

AVX, Tantalum

TPS Series III (SMD)

10

470

0.045

>1723

7,3 L× 5,7 W

≤5

TPSE477M019R0045

×4,1H

TPS (SMD)

10

330

0.045

>1723

≤5

TPSE337M019R0045

H

Kemet

T520, Poly-Tantalum ( SMD)

10

470

0.040

1800

≤5

T520X477M006ASE040

H

T530, Tantalum/Organic

4

680

0.010

>5100

≤1

T530X687M004ASE010

(SMD)

H

6.3

470

0.010

5200

≤1

T530X477M006ASE010

H

Vishay-Sprague

594D, Tantalum (SMD)

10

470

0.100

1440

≤5

595D477X0010R2T

94SA, organic (Radial )

16

1000

0.015

>9700

16 × 25

1

≤2

94Sa108X0016HBP

94SVP, Organic (SMD)

16

330

0.017

>4500

10 × 12,7

2

≤2

94SVP477X0016F12

(1) Capacitor Supplier Verification

Please verify availability of capacitors identified in this table. Capacitor suppliers may recommend alternative part numbers because of

limited availability or obsolete products. In some instances, the capacitor product life cycle may be in decline and have short-term

consideration for obsolescence.

RoHS, Lead-free and Material Details

Please consult capacitor suppliers regarding material composition, RoHS status, lead-free status, and manufacturing process

requirements. Component designators or part number deviations can occur when material composition or soldering requirements are

updated.

(2) N/R – Not recommended. The capacitor voltage rating does not meet the minimum operating limits.

(3) A total capacitance of 540 µF is acceptable based on the combined ripple current rating.

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