Datasheet

TPS40060
TPS40061
www.ti.com SLUS543F –DECEMBER 2002–REVISED JUNE 2013
REVISION HISTORY
Changes from Revision E (June 2006) to Revision F Page
• Changed reference to Figure 13, PowerPad Dimensions, to Figure 14, Design Example, 48 V to 3.3 V at 5 A dc-to-
dc Converter ......................................................................................................................................................................... 7
• Changed both (C
SS
– 0.85 V) voltages to (V
CSS
– 0.85 V) in Programming Soft Start ....................................................... 10
• Changed turn-on (I
L
) to start-up (I
LOAD
) in the third paragraph of Programming Current Limit section. ............................. 11
• Changed first instance of BPN10 to BP10 in respective section title. ................................................................................ 11
• Added high-side before MOSFET in the Calculating the BP10 and BP10V Bypass Capacitor section ............................. 12
• Changed HDRV signal goes high to ...goes low in the Synchronizing to an External Supply section ............................... 13
• Added equation definition for f
SYNC
to Equation 10 ............................................................................................................. 13
• Deleted k from KΩ at the end of equation Equation 11 ...................................................................................................... 13
• Added (dummy) to R
T
in Equation 11 definition ................................................................................................................. 13
• Changed sequence of equation substitutions from: Equation 14 into Equation 13, Equation 16 into Equation 15,
Equation 13 equal to Equation 15, to: Equation 15 into Equation 14, Equation 17 into Equation 16, Equation 14
equal to Equation 16 ........................................................................................................................................................... 14
• Added generic before modulator gain in first paragraph of the Loop Compensation section ............................................ 14
• Deleted with V
IN
being the minimum input voltage required to cause the ramp excursion to cover the entire switching
period. from first paragraph of the Loop Compensation section ........................................................................................ 14
• Deleted previous Equation 19, which was A
MOD
= V
IN
/ V
S
or A
MOD(db)
= 20 × log (V
IN
/ V
S
) ............................................. 14
• Changed figure reference for modulator gain in the Loop Compensation from Figure 6 (Typical Current Limit
Protection Waveforms) to Figure 8 (PWM MODULATOR RELATIONSHIPS) ................................................................... 14
• Added moderator DC gain and new Equation 20 to Loop Compensation section ............................................................. 15
• Changed V
OUT
to V
O
in sentence before and in Equation 23 .............................................................................................. 15
• Changed calculated in to set by in sentence before Equation 24 ...................................................................................... 15
• Changed V
IN
/ V
S
to V
IN(min)
/ V
RAMP
in the Modulator Gain vs Switching Frequency graph ............................................... 15
• Changed the TC
R
minimum value from 0.0035 to 3500 and the maximum from 0.010 to 10000 in the second
paragraph of the High-Side MOSFET Power Dissipation section ...................................................................................... 17
• Changed V
DD
to V
IN
in Equation 41 .................................................................................................................................... 19
• Changed PowerPAD Dimensions to include x and y axis values ....................................................................................... 20
• Added high-side MOSFET to step four title ........................................................................................................................ 22
• Changed reference to substituting Equation 30 to Equation 47 ......................................................................................... 22
• Deleted I
RMS
2
× R
DS(ON)
from synchronous MOSFET conduction equation ........................................................................ 23
• Changed synchronous MOSFET conduction equation equals value from 0.10 to 0.485 ................................................... 23
• Changed body diode conduction equation values: 100 ns to 50 ns and 0.104 W to 0.052 W ........................................... 23
• Changed power dissipation equation values: 0.1 to 0.485, 0.104 to 0.052, 0.311 W to 0.644 W ..................................... 23
• Changed junction temperature equation values: (0.311) to 0.644, 97°C to 111°C ............................................................ 23
• Changed Step 6 reference to Equation 11 to Equation 12 ................................................................................................. 23
• Changed inductor value equation in Step 6: replaced value of 48 with 55 and 11.8 with 11.9 .......................................... 23
• Changed R
KFF
equation values in Step 8:133.7 to 309 kΩ, 133 to 301 kΩ ........................................................................ 23
• Added 80%x before V
IN(min)
in R
KFF
equation in Step 8 ....................................................................................................... 23
• Changed first ESR value in Step 9 from 12.7 to 8.9 mΩ .................................................................................................... 24
• Changed second ESR value in Step 9 from 13.8 to 11.1 mΩ ............................................................................................ 24
• Changed DC modulator gain values in both equations: 10 to 18, 5 to 9; (5.0) to 9, 14 to 19 dB ...................................... 24
• Changed AMOD crossover frequency equation values: 5 to 9, 0.68 to 1.23 ..................................................................... 25
• Changed gain (G) equation values: 0.68 to 1.23, 1.46 to 0.81 .......................................................................................... 25
• Changed poles and zeros equation values: Equation 73, 73.3 to 73.7 kHZ, 4.62 to 4.59 kΩ; Equation 74, 3.29 to
0.81, 1.46 to 10 kHZ, 109 to 196 pF, 100 to 220 pF; Equation 75, 100 to 200 pF, 73.3 to 73.7 kHz, 21.7 to 9.82 kΩ,
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