PTH08T240FAZT [TI]

10-A, 4.5-V to 14-V INPUT, NON-ISOLATED POWER MODULE FOR 3-GHz DSP SYSTEMS; 10 -A , 4.5 V至14 V输入,非隔离式电源模块,用于3 GHz的DSP系统
PTH08T240FAZT
型号: PTH08T240FAZT
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

10-A, 4.5-V to 14-V INPUT, NON-ISOLATED POWER MODULE FOR 3-GHz DSP SYSTEMS
10 -A , 4.5 V至14 V输入,非隔离式电源模块,用于3 GHz的DSP系统

电源电路 输出元件 输入元件
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PTH08T240F  
www.ti.com ........................................................................................................................................ SLTS277CDECEMBER 2006REVISED DECEMBER 2008  
10-A, 4.5-V to 14-V INPUT, NON-ISOLATED  
POWER MODULE FOR 3-GHz DSP SYSTEMS  
1
FEATURES  
2
Up to 10-A Output Current  
TurboTrans™ Technology  
4.5-V to 14-V Input Voltage  
Designed to meet Ultra-Fast Transient  
Requirements for 3-GHz DSP Systems  
Wide-Output Voltage Adjust (0.69 V to 2.0 V)  
±1.5% Total Output Voltage Variation  
Efficiencies up to 93%  
15 mV Output Voltage Deviation  
(CO = 2000 µF, ΔI = 3 A)  
Output Overcurrent Protection  
(Nonlatching, Auto-Reset)  
APPLICATIONS  
Wireless Infrastructure Base Stations  
Operating Temperature: –40°C to 85°C  
Safety Agency Approvals:  
UL/IEC/CSA-C22.2 60950-1  
Prebias Startup  
On/Off Inhibit  
Differential Output Voltage Remote Sense  
Adjustable Undervoltage Lockout  
Auto-Track™ Sequencing  
SmartSync Technology  
DESCRIPTION  
The PTH08T240F is a high-performance 10-A rated, non-isolated power module designed to meet ultra-fast  
transient requirements for 3-GHz DSP systems like Texas Instrument's TMS320TCI6488. This module is an  
addition to the 2nd generation of the popular PTH series power modules which include a reduced footprint and  
additional features.  
Operating from an input voltage range of 4.5 V to 14 V, the PTH08T240F requires a single resistor to set the  
output voltage to any value over the range, 0.69 V to 2.0 V. The output voltage range makes the PTH08T240F  
particularly suitable for the 3-GHz DSP's core voltage requirements.  
The module incorporates a comprehensive list of features. Output over-current and over-temperature shutdown  
protects against most load faults. A differential remote sense ensures tight load regulation. An adjustable  
under-voltage lockout allows the turn-on voltage threshold to be customized. Auto-Track™sequencing is a  
popular feature that greatly simplifies the simultaneous power-up and power-down of multiple modules in a  
power system.  
The PTH08T240F includes new patented technologies, TurboTrans™ and SmartSync. The TurboTrans feature  
optimizes the transient response of the regulator while simultaneously reducing the quantity of external output  
capacitors required to meet a target voltage deviation specification. TurboTrans allows PTH08T240F to meet the  
tight transient voltage tolerances required by 3-GHz DSPs with minimal output capacitance. SmartSync allows for  
switching frequency synchronization of multiple modules, thus simplifying EMI noise suppression tasks and  
reducing input capacitor RMS current requirements. The module uses double-sided surface mount construction  
to provide a low profile and compact footprint. Package options include both through-hole and surface mount  
configurations that are lead (Pb) - free and RoHS compatible.  
1
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.  
2
Auto-Track, TurboTrans, TMS320 are trademarks of Texas Instruments.  
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.  
Copyright © 2006–2008, Texas Instruments Incorporated  
PTH08T240F  
SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
SmartSync  
Track  
TurboTrans  
RTT  
1%  
10  
1
9
0.05W  
(Required)  
Track SYNC  
TT  
V
I
2
6
+Sense  
+Sense  
V
I
5
7
V
O
PTH08T240F  
V
O
Inhibit  
11  
INH/UVLO  
GND GND  
-Sense  
Adj  
L
O
A
D
V
O
C
O
1000 mF  
+
+
[A]  
3
4
8
R
SET  
R
UVLO  
2
1%  
0.05 W  
(Required)  
(Required)  
C
C
I
1%  
0.05 W  
(Optional)  
I
220 mF  
22 mF  
(Required) (Recommended)  
-Sense  
GND  
GND  
UDG-07125  
A. RSET required to set the output voltage to a value higher than 0.69 V. See Electrical Characteristics table.  
2
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PTH08T240F  
www.ti.com ........................................................................................................................................ SLTS277CDECEMBER 2006REVISED DECEMBER 2008  
ORDERING INFORMATION  
For the most current package and ordering information, see the Package Option Addendum at the end of this datasheet, or see  
the TI website at www.ti.com.  
DATASHEET TABLE OF CONTENTS  
DATASHEET SECTION  
ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS  
ELECTRICAL CHARACTERISTICS TABLE  
TERMINAL FUNCTIONS  
PAGE NUMBER  
3
4
5
TYPICAL CHARACTERISTICS (VI = 5V)  
TYPICAL CHARACTERISTICS (VI = 8V)  
TYPICAL CHARACTERISTICS (VI = 12V)  
ADJUSTING THE OUTPUT VOLTAGE  
INPUT & OUTPUT CAPACITOR RECOMMENDATIONS  
TURBOTRANS™ INFORMATION  
UNDERVOLTAGE LOCKOUT (UVLO)  
SOFT-START POWER-UP  
6
7
8
9
11  
15  
21  
22  
23  
24  
24  
24  
25  
26  
29  
31  
OUTPUT INHIBIT  
OVER-CURRENT PROTECTION  
OVER-TEMPERATURE PROTECTION  
REMOTE SENSE  
SYCHRONIZATION (SMARTSYNC)  
AUTO-TRACK SEQUENCING  
PREBIAS START-UP  
TAPE & REEL AND TRAY DRAWINGS  
ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS  
(Voltages are with respect to GND)  
UNIT  
VTrack Track pin voltage  
–0.3 to VI + 0.3  
–40 to 85  
260  
V
TA  
Operating temperature range Over VI range  
Surface temperature of module body or  
pins for 5 seconds maximum.  
Twave Wave soldering temperature  
Treflow Solder reflow temperature  
suffix AD  
°C  
suffix AS  
suffix AZ  
235(1)  
260(1)  
Surface temperature of module body or  
pins  
Tstg  
Storage temperature  
Mechanical shock  
–55 to 125(2)  
Per Mil-STD-883D, Method 2002.3 1  
msec, 1/2 sine, mounted  
suffix AH & AD  
suffix AS & AZ  
500  
250  
15  
G
Mechanical vibration  
Weight  
Mil-STD-883D, Method 2007.2 20-2000 Hz  
5
grams  
Flammability  
Meets UL94V-O  
(1) During reflow of surface mount package version do not elevate peak temperature of the module, pins or internal components above the  
stated maximum.  
(2) The shipping tray or tape and reel cannot be used to bake parts at temperatures higher than 65°C.  
Copyright © 2006–2008, Texas Instruments Incorporated  
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PTH08T240F  
SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
ELECTRICAL CHARACTERISTICS  
PTH08T240F  
TA = 25°C, VI = 5 V, VO = 1.0 V, CI = 220 µF, CO = 1000 µF, and IO = IO max (unless otherwise stated)  
PARAMETER  
TEST CONDITIONS  
PTH08T240F  
TYP  
UNIT  
MIN  
0
MAX  
IO  
Output current  
Over VO range  
Over IO range  
Over IO range  
25°C, natural convection  
10  
A
V
(1)  
0.69V VO < 1.3V  
1.3V VO 2.0  
4.5  
4.5  
0.69  
14  
VI  
Input voltage range  
14  
VOADJ  
Output voltage adjust range  
Set-point voltage tolerance  
Temperature variation  
Line regulaltion  
2.0  
V
(2)  
±0.5  
±0.3  
±3  
±1  
%VO  
%VO  
mV  
–40°C < TA < 85°C  
Over VI range  
VO  
Load regulation  
Over IO range  
±2  
mV  
(2)  
Total output variation  
Includes set-point, line, load, –40°C TA 85°C  
RSET = 4.78 k, VO = 1.8 V  
±1.5  
%VO  
90%  
88%  
87%  
85%  
RSET = 7.09 k, VO = 1.5 V  
IO = 10 A  
η
Efficiency  
RSET = 12.1 k, VO = 1.2 V  
RSET = 20.8 k, VO = 1.0 V  
20-MHz bandwidth  
(1)  
VO Ripple (peak-to-peak)  
Overcurrent threshold  
10  
mVPP  
A
ILIM  
ttr  
Reset, followed by auto-recovery  
20  
500  
25  
Recovery time  
VO over/undershoot  
Recovery time  
µs  
CO = 1000 µF, Type C  
RTT=open  
2.5 A/µs load step  
0.5 A to 3.5 A step  
VO = 0.9 V  
ΔVtr  
ttrTT  
ΔVtrTT  
IIL  
mV  
µs  
Transient response  
800  
14  
CO = 2000 µF, Type C  
RTT=24.3kΩ  
VO over/undershoot  
mV  
µA  
Track input current (pin 10)  
Pin to GND  
–130(3)  
1
dVtrack/dt Track slew rate capability  
CO CO (max)  
V/ms  
VI increasing, RUVLO = OPEN  
VI decreasing, RUVLO = OPEN  
Hysteresis, RUVLO 52.3 kΩ  
4.3  
4.2  
0.5  
4.45  
Adjustable Under-voltage lockout  
UVLOADJ  
(pin 11)  
3.7  
V
Input high voltage (VIH  
)
Open(4)  
0.8  
V
Inhibit control (pin 11)  
Input low voltage (VIL)  
-0.2  
Input low current (IIL), Pin 11 to GND  
-235  
5
µA  
mA  
kHz  
kHz  
V
Iin  
Input standby current  
Inhibit (pin 11) to GND, Track (pin 10) open  
f s  
Switching frequency  
Over VI and IO ranges, SmartSync (pin 1) to GND  
260  
240  
2
300  
340  
400  
5.5  
0.8  
fSYNC  
VSYNCH  
VSYNCL  
tSYNC  
Synchronization frequency  
SYNC High-Level Input Voltage  
SYNC Low-Level Input Voltage  
SYNC Minimum Pulse Width  
V
200  
nSec  
(5)  
Nonceramic  
220  
CI  
External input capacitance  
µF  
µF  
(5)  
Ceramic  
22  
(6)  
Capacitance Value  
Nonceramic 1000  
10000  
CO  
External output capacitance  
Reliability  
Capacitance × ESR product (CO × ESR)  
Telcordia SR-332, 50% stress, TA= 40°C, ground benign  
1000  
6.1  
10000 µF×mΩ  
106 Hr  
MTBF  
(1) For output voltages less than 1.3 V, the ripple may increase (up to 2×) when operating at input voltages greater than (VO × 11). See the  
SmartSync section and the TurboTrans section of the datasheet for additional information.  
(2) The set-point voltage tolerance is affected by the tolerance and stability of RSET. The stated limit is unconditionally met if RSET has a  
tolerance of 1% with 100 ppm/°C or better temperature stability.  
(3) A low-leakage (<100 nA), open-drain device, such as MOSFET or voltage supervisor IC, is recommended to control pin 10. The  
open-circuit voltage is less than 8 Vdc  
.
(4) This control pin has an internal pull-up. Do not place an external pull-up on this pin. If it is left open-circuit, the module operates when  
input power is applied. A small, low-leakage (<100 nA) MOSFET is recommended for control. For additional information, see the related  
application information section.  
(5) A 220 µF electrolytic input capacitor is required for proper operation. The electrolytic capacitor must be rated for a minimum of 500 mA  
rms of ripple current. An additional 22-µF ceramic input capacitor is recommended to reduce rms ripple current.  
(6) 1000 µF of external low-ESR output capacitance is required for basic operation. See the Capacitor Recommendation section and  
TurboTrans Application Information section for more guidance.  
4
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PTH08T240F  
www.ti.com ........................................................................................................................................ SLTS277CDECEMBER 2006REVISED DECEMBER 2008  
TERMINAL FUNCTIONS  
TERMINAL  
DESCRIPTION  
NAME  
VI  
NO.  
2
The positive input voltage power node to the module, which is referenced to common GND.  
The regulated positive power output with respect to GND.  
VO  
5
This is the common ground connection for the VI and VO power connections. It is also the 0 Vdc reference for the  
control inputs.  
GND  
3, 4  
The Inhibit pin is an open-collector/drain, negative logic input that is referenced to GND. Applying a low level  
ground signal to this input disables the module’s output and turns off the output voltage. When the Inhibit control  
is active, the input current drawn by the regulator is significantly reduced. If the Inhibit pin is left open-circuit, the  
module produces an output whenever a valid input source is applied.  
Inhibit(1) and  
UVLO  
11  
This pin is also used for input undervoltage lockout (UVLO) programming. Connecting a resistor from this pin to  
GND (pin 3) allows the ON threshold of the UVLO to be adjusted higher than the default value. For more  
information, see the Application Information section.  
A 0.05 W 1% resistor must be directly connected between this pin and pin 7 (–Sense) to set the output voltage  
to a value higher than 0.69 V. The temperature stability of the resistor should be 100 ppm/°C (or better). The  
setpoint range for the output voltage is from 0.69 V to 2.0 V. If left open circuit, the output voltage will default to  
its lowest value. For further information, on output voltage adjustment see the related application note.  
Vo Adjust  
8
The specification table gives the preferred resistor values for a number of standard output voltages.  
The sense input allows the regulation circuit to compensate for voltage drop between the module and the load.  
For optimal voltage accuracy, +Sense must be connected to VO, very close to the load.  
+ Sense  
– Sense  
6
7
The sense input allows the regulation circuit to compensate for voltage drop between the module and the load.  
For optimal voltage accuracy –Sense must be connected to GND (pin 4) very close to the module (within 10 cm).  
This is an analog control input that enables the output voltage to follow an external voltage. This pin becomes  
active typically 20 ms after the input voltage has been applied, and allows direct control of the output voltage  
from 0 V up to the nominal set-point voltage. Within this range the module's output voltage follows the voltage at  
the Track pin on a volt-for-volt basis. When the control voltage is raised above this range, the module regulates  
at its set-point voltage. The feature allows the output voltage to rise simultaneously with other modules powered  
from the same input bus. If unused, this input should be connected to VI.  
Track  
10  
NOTE: Due to the undervoltage lockout feature, the output of the module cannot follow its own input voltage  
during power up. For more information, see the related application note.  
This input pin adjusts the transient response of the regulator. To activate the TurboTrans™ feature, a 1%,  
50 mW resistor must be connected between this pin and pin 6 (+Sense) very close to the module. For a given  
value of output capacitance, a reduction in peak output voltage deviation is achieved by utililizing this feature.  
The resistance requirement can be selected from the TurboTrans™ resistor table in the Application Information  
section. External capacitance must never be connected to this pin unless the TurboTrans resistor value is a  
short, 0 .  
TurboTrans™  
9
1
This input pin sychronizes the switching frequency of the module to an external clock frequency. The SmartSync  
feature can be used to sychronize the switching fequency of multiple PTH08T240F modules, aiding EMI noise  
suppression efforts. If unused, this pin should be connected to GND (pin 3). For more information, please review  
the Application Information section.  
SmartSync  
(1) Denotes negative logic: Open = Normal operation, Ground = Function active  
11  
1
10  
9
2
8
7
PTH08T240F  
(Top View)  
6
3
4
5
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SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
TYPICAL CHARACTERISTICS(1)(2)  
CHARACTERISTIC DATA (VI = 5 V)  
EFFICIENCY  
vs  
LOAD CURRENT  
OUTPUT RIPPLE  
vs  
LOAD CURRENT  
POWER DISSIPATION  
vs  
LOAD CURRENT  
12  
2.5  
100  
95  
V
= 5 V  
V
I
= 5 V  
V
= 5 V  
2.0 V  
I
I
10  
8
90  
85  
80  
75  
70  
65  
60  
55  
50  
2.0  
1.5  
1.1 V  
2.0 V  
1.1 V  
6
4
2.0 V  
0.9 V  
1.1 V  
0.9 V  
1.0  
0.5  
0.9 V  
V
(V)  
V
(V)  
V
(V)  
O
O
O
2.0  
1.1  
0.9  
2
0
2.0  
1.1  
0.9  
2.0  
1.1  
0.9  
0
0
2
4
6
8
10  
0
2
4
6
- Output Current - A  
8
10  
0
2
4
6
8
10  
I
I
- Output Current - A  
O
O
I
- Output Current - A  
O
Figure 1.  
Figure 2.  
Figure 3.  
SAFE OPERATING AREA  
90  
80  
Natural  
Convection  
70  
60  
50  
40  
30  
20  
V
= 5 V  
I
All V  
O
0
2
4
6
8
10  
I
- Output Current - A  
O
Figure 4.  
(1) The electrical characteristic data has been developed from actual products tested at 25°C. This data is considered typical for the  
converter. Applies to Figure 1, Figure 2, and Figure 3.  
(2) The temperature derating curves represent the conditions at which internal components are at or below the manufacturer's maximum  
operating temperatures. Derating limits apply to modules soldered directly to a 100 mm x 100 mm double-sided PCB with 2 oz. copper.  
For surface mount packages (AS and AZ suffix), multiple vias must be utilized. Please refer to the mechanical specification for more  
information. Applies to Figure 4.  
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TYPICAL CHARACTERISTICS(1)(2)  
CHARACTERISTIC DATA (VI = 8 V)  
EFFICIENCY  
vs  
LOAD CURRENT  
OUTPUT RIPPLE  
vs  
LOAD CURRENT  
POWER DISSIPATION  
vs  
LOAD CURRENT  
10  
8
100  
95  
3.0  
V
= 8 V  
V
= 8 V  
V
I
= 8 V  
I
I
2.0 V  
2.5  
2.0  
90  
85  
80  
75  
70  
65  
60  
55  
50  
2.0 V  
2.0 V  
1.1 V  
6
4
0.9 V  
1.1 V  
1.5  
1.1 V  
1.0  
0.5  
V
(V)  
V
(V)  
V
(V)  
O
O
O
2
0
2.0  
1.1  
0.9  
2.0  
1.1  
0.9  
2.0  
1.1  
0.9  
0.9 V  
0.9 V  
0
0
2
4
6
8
10  
0
2
4
6
8
10  
0
2
4
6
8
10  
I
- Output Current - A  
O
I
- Output Current - A  
I
- Output Current - A  
O
O
Figure 5.  
Figure 6.  
Figure 7.  
SAFE OPERATING AREA  
90  
80  
70  
60  
50  
40  
Natural  
Convection  
V
= 8 V  
I
30  
20  
All V  
O
0
2
4 6  
- Output Current - A  
8
10  
I
O
Figure 8.  
(1) The electrical characteristic data has been developed from actual products tested at 25°C. This data is considered typical for the  
converter. Applies to Figure 5, Figure 6, and Figure 7.  
(2) The temperature derating curves represent the conditions at which internal components are at or below the manufacturer's maximum  
operating temperatures. Derating limits apply to modules soldered directly to a 100 mm x 100 mm double-sided PCB with 2 oz. copper.  
For surface mount packages (AS and AZ suffix), multiple vias must be utilized. Please refer to the mechanical specification for more  
information. Applies to Figure 8.  
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TYPICAL CHARACTERISTICS(1)(2)(3)  
CHARACTERISTIC DATA (VI = 12 V)  
EFFICIENCY  
vs  
OUTPUT CURRENT  
OUTPUT RIPPLE  
vs  
OUTPUT CURRENT  
POWER DISSIPATION  
vs  
OUTPUT CURRENT  
3.0  
100  
95  
16  
14  
12  
10  
8
V
= 12 V  
V
= 12 V  
V
= 12 V  
I
I
I
2.5  
2.0  
2.0 V  
90  
85  
80  
75  
70  
65  
60  
55  
50  
0.9 V  
2.0 V  
2.0 V  
1.1 V  
1.5  
1.0  
1.1 V  
0.9 V  
0.9 V  
(V)  
6
4
V
(V)  
O
V
O
V
(V)  
O
2.0  
1.1  
0.9  
0.5  
0
2.0  
1.1  
0.9  
2.0  
1.1  
0.9  
2
1.1 V  
0
0
2
4
6
8
10  
0
2
4
6
8
10  
0
2
4
6
8
10  
I
- Output Current - A  
I
- Output Current - A  
O
O
I
- Output Current - A  
O
Figure 9.  
Figure 10. See Note 2 below  
SAFE OPERATING AREA  
Figure 11.  
90  
80  
Natural  
Convection  
70  
60  
50  
40  
30  
20  
V
= 12 V  
I
All V  
O
0
2
4
6
8
10  
I
- Output Current - A  
O
Figure 12.  
(1) The electrical characteristic data has been developed from actual products tested at 25°C. This data is considered typical for the  
converter. Applies to , Figure 9, Figure 11 and Figure 10.  
(2) Output ripple may increase up to 2x when operating at input voltages greater than (VO x 11). See the Smart Sync section of the  
datasheet for input voltage and frequency limitations.  
(3) The temperature derating curves represent the conditions at which internal components are at or below the manufacturer's maximum  
operating temperatures. Derating limits apply to modules soldered directly to a 100 mm x 100 mm double-sided PCB with 2 oz. copper.  
For surface mount packages (AS and AZ suffix), multiple vias must be utilized. Please refer to the mechanical specification for more  
information. Applies to Figure 12.  
8
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APPLICATION INFORMATION  
ADJUSTING THE OUTPUT VOLTAGE  
The VOAdjust control (pin 8) sets the output voltage of the PTH08T240F. The adjustment range is 0.69 V to  
2.0 V. The adjustment method requires the addition of a single external resistor, RSET, that must be connected  
directly between the VOAdjust and – Sense pins. Table 1 gives the standard value of the external resistor for a  
number of standard voltages, along with the actual output voltage that this resistance value provides.  
For other output voltages, the value of the required resistor can either be calculated using the following formula,  
or simply selected from the range of values given in Table 2. Figure 13 shows the placement of the required  
resistor.  
0.69  
- 0.69  
R
= 10 kW x  
- 1.43 kW  
SET  
V
O
(1)  
Table 1. Standard Values of RSET for Standard Output Voltages  
VO (Standard) (V)  
RSET (Standard Value) (k)  
VO (Actual) (V)  
1.807  
1.8  
1.5  
1.2  
1.1  
1
4.75  
6.98  
12.1  
15.4  
20.5  
31.6  
1.510  
1.200  
1.100  
1.004  
0.9  
0.899  
6
+Sense  
+Sense  
V
O
5
V
O
PTH08T240F  
7
−Sense  
VoAdj  
8
GND  
GND  
+
4
3
C
O
R
SET  
1%  
0.05 W  
−Sense  
GND  
UDG−06077  
(1) RSET: Use a 0.05-W resistor with a tolerance of 1% and temperature stability of 100 ppm/°C (or better). Connect the  
resistor directly between pins 8 and 7, as close to the regulator as possible, using dedicated PCB traces.  
(2) Never connect capacitors to VOAdjust (pin 8). Any capacitance added to the VOAdjust pin affects the stability of the  
regulator.  
Figure 13. VO Adjust Resistor Placement  
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Table 2. Output Voltage Set-Point Resistor Values (Standard Values)  
VO Required (V)  
RSET (kΩ)  
681  
(1)  
0.70  
(1)  
0.75  
113  
(1)  
0.80  
61.9  
41.2  
31.6  
24.9  
20.5  
17.8  
15.4  
13.3  
12.1  
10.7  
9.88  
9.09  
8.25  
7.68  
6.98  
6.49  
6.04  
5.76  
5.36  
5.11  
4.75  
4.53  
4.22  
4.02  
3.83  
(1)  
0.85  
(1)  
0.90  
(1)  
0.95  
(1)  
1.00  
(1)  
1.05  
(1)  
1.10  
(1)  
1.15  
(1)  
1.20  
1.25(1)  
1.30  
1.35  
1.40  
1.45  
1.50  
1.55  
1.60  
1.65  
1.70  
1.75  
1.80  
1.85  
1.90  
1.95  
2.00  
(1) For output voltages less than 1.3 V, the ripple may increase (up to 2×) when operating at input  
voltages greater than (VO × 11). See the SmartSync section and the TurboTrans section of the  
datasheet for more information.  
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CAPACITOR RECOMMENDATIONS FOR THE PTH08T240F POWER MODULE  
Capacitor Technologies  
Electrolytic Capacitors  
When using electrolytic capacitors, high quality, computer-grade electrolytic capacitors are recommended.  
Aluminum electrolytic capacitors provide adequate decoupling over the frequency range, 2 kHz to 150 kHz,  
and are suitable when ambient temperatures are above -20°C. For operation below -20°C, tantalum,  
ceramic, or OS-CON type capacitors are required.  
Ceramic Capacitors  
Above 150 kHz the performance of aluminum electrolytic capacitors is less effective. Multilayer ceramic  
capacitors have very low ESR and a resonant frequency higher than the bandwidth of the regulator. They  
can be used to reduce the reflected ripple current at the input as well as improve the transient response of  
the output.  
Tantalum, Polymer-Tantalum Capacitors  
Tantalum type capacitors may only used on the output bus, and are recommended for applications where the  
ambient operating temperature is less than 0°C. The AVX TPS series and Kemet capacitor series are  
suggested over many other tantalum types due to their lower ESR, higher rated surge, power dissipation,  
and ripple current capability. Tantalum capacitors that have no stated ESR or surge current rating are not  
recommended for power applications.  
Input Capacitor (Required)  
The PTH08T240F requires a minimum input capacitance of 220 µF electrolytic type. The ripple current rating of  
the electrolytic capacitor must be at least 500 mArms. An additional 22-µF X5R/X7R ceramic is recommended to  
reduce the RMS ripple current.  
Input Capacitor Information  
The size and value of the input capacitor is determined by the converter’s transient performance capability. This  
minimum value assumes that the converter is supplied with a responsive, low inductance input source. This  
source should have ample capacitive decoupling, and be distributed to the converter via PCB power and ground  
planes.  
Ceramic capacitors should be located as close as possible to the module's input pins, within 0.5 inch (1,3 cm).  
Adding ceramic capacitance is necessary to reduce the high-frequency ripple voltage at the module's input. This  
will reduce the magnitude of the ripple current through the electroytic capacitor, as well as the amount of ripple  
current reflected back to the input source. Additional ceramic capacitors can be added to further reduce the RMS  
ripple current requirement for the electrolytic capacitor.  
Increasing the minimum input capacitance to 680 µF is recommended for high-performance applications, or  
wherever the input source performance is degraded.  
The main considerations when selecting input capacitors are the RMS ripple current rating, temperature stability,  
and less than 100 mof equivalent series resistance (ESR).  
Regular tantalum capacitors are not recommended for the input bus. These capacitors require a recommended  
minimum voltage rating of 2 × (maximum dc voltage + ac ripple). This is standard practice to ensure reliability.  
No tantalum capacitors were found with a sufficient voltage rating to meet this requirement.  
When the operating temperature is below 0°C, the ESR of aluminum electrolytic capacitors increases. For these  
applications, OS-CON, poly-aluminum, and polymer-tantalum types should be considered.  
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Output Capacitor (Required)  
The PTH08T240F requires a minimum output capacitance of 1000 µF of aluminum, polymer-aluminum, tantulum,  
or polymer-tantalum type.  
The required capacitance above the minimum is determined by actual transient deviation requirements. See the  
TurboTrans Technology application section within this document for specific capacitance selection.  
Output Capacitor Information  
When selecting output capacitors, the main considerations are capacitor type, temperature stability, and ESR.  
Consider the capacitance X ESR product (see the following section).  
Ceramic output capacitors added for high-frequency bypassing should be located as close as possible to the  
load to be effective. Ceramic capacitor values below 10 µF should not be included when calculating the total  
output capacitance value.  
When the operating temperature is below 0°C, the ESR of aluminum electrolytic capacitors increases. For these  
applications, OS-CON, poly-aluminum, and polymer-tantalum types should be considered.  
TurboTrans Output Capacitance  
TurboTrans allows the designer to optimize the output capacitance according to the system transient design  
requirement. High quality, ultra-low ESR capacitors are required to maximize TurboTrans effectiveness. The  
capacitor's capacitance (µF) × ESR (m) product determines its capacitor type; Type B, or C. Capacitor types  
are defined as follows:  
Type B = (1000 < capacitance × ESR 5000) (e.g. polymer-tantalum)  
Type C = (5000 < capacitance × ESR 10,000) (e.g. OS-CON)  
When using more than one type of output capacitor, select the capacitor type that makes up the majority of your  
total output capacitance. When calculating the C×ESR product, use the maximum ESR value from the capacitor  
manufacturer's datasheet.  
Working Examples:  
A capacitor with a capacitance of 330 µF and an ESR of 5 m, has a C × ESR product of 1650 µF x m(330 µF  
× 5 m). This is a Type B capacitor. A capacitor with a capacitance of 1000 µF and an ESR of 8 m, has a  
C × ESR product of 8000 µF x m(1000 µF × 8 m). This is a Type C capacitor.  
See the TurboTrans Technology application section within this document for specific capacitance selection.  
Table 3 includes a preferred list of capacitors by type and vendor. See the Output Bus / TurboTrans column.  
Designing for Fast Load Transients  
The transient response of the dc/dc converter has been characterized using a load transient with a di/dt of  
2.5 A/µs. The typical voltage deviation for this load transient is given in the Electrical Characteristics table using  
the minimum required 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 can only be met with  
additional low ESR ceramic capacitor decoupling. Generally, with load steps greater than 100 A/µs, adding  
multiple 10 µF ceramic capacitors plus 10 × 1 µF, and numerous high frequency ceramics (0.1 µF) is all that is  
required to soften the transient higher frequency edges. The PCB location of these capacitors in relation to the  
load is critical. DSP, FPGA and ASIC vendors identify types, location and amount of capacitance required for  
optimum performance. Low impedance buses, unbroken PCB copper planes, and components located as close  
as possible to the high frequency devices are essential for optimizing transient performance.  
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Table 3. Input/Output Capacitors(1)  
Capacitor Characteristics  
Quantity  
Output Bus  
Max  
Max  
Ripple  
Capacitor Vendor,  
Type Series (Style)  
Working  
Voltage  
(V)  
ESR  
at 100  
kHz  
Value  
(µF)  
Current  
at 85°C  
(Irms)  
(mA)  
Physical  
Size (mm)  
Input  
Bus  
Vendor Part No.  
TurboTrans  
Cap Type(2)  
(m)  
Panasonic  
FC (Radial)  
25  
25  
25  
25  
270  
560  
470  
470  
90  
65  
65  
80  
755  
1205  
1200  
850  
10 × 12,5  
12,5 × 15  
12,5 × 16,5  
10 ×10,2  
1(3)  
1(3)  
1(3)  
1(3)  
N/R(4)  
N/R(4)  
N/R(4)  
N/R(4)  
EEUFC1E271  
FC (Radial)  
EEUFC1E561S  
EEVFC1E471LQ  
EEVFK1E471P  
FC(SMD)  
FK(SMD)  
United Chemi-Con  
PTB(SMD) Poly-Tantalum  
LXZ, Aluminum (Radial)  
PS, Poly-Alum(Radial)  
PXA, Poly-Alum(SMD)  
PS, Poly-Alum(Radial)  
PXA, Poly-Alum(Radial)  
Nichicon, Aluminum  
HD (Radial)  
6.3  
25  
16  
16  
10  
10  
330  
330  
330  
330  
270  
330  
25  
90  
14  
14  
14  
14  
2600  
760  
7,3x4,3x2.8  
10 × 12,5  
10 × 12,5  
10 × 12,2  
8 × 11,5  
N/R(5)  
1(3)  
1(3)  
1(3)  
1(3)  
1(3)  
C 3(2)  
N/R(4)  
B 3(2)  
B 3(2)  
B 4(2)  
B 3(2)  
4PTB337MD6TER  
LXZ25VB331M10X12LL  
16PS330MJ12  
5060  
5050  
4420  
4420  
PXA16VC331MJ12TP  
10PS270MH11  
8 × 12  
PXA10VC331MH12  
25  
25  
35  
2.0  
220  
330  
560  
390  
72  
95  
48  
5
760  
750  
8 × 11,5  
10 × 15  
1(3)  
1(3)  
1(3)  
N/R(4)  
N/R(4)  
N/R(4)  
B 3(2)  
UHD1E221MPR  
PM (Radial)  
UPM1E331MPH6  
PM (Radial)  
1360  
4000  
16 × 15  
UPM1V561MHH6  
EEFSE0J391R (VO1.6V)(6)  
Panasonic, Poly-Aluminum  
Sanyo  
7,3×4,3×4,2  
N/R(5)  
TPE, Poscap (SMD)  
TPE Poscap(SMD)  
TPD Poscap (SMD)  
SEP, OS-CON (Radial)  
SP OS-CON ( Radial)  
SEPC, OS-CON (Radial)  
SVP, OS-CON (SMD)  
10  
2.5  
2.5  
16  
16  
16  
16  
330  
470  
1000  
330  
270  
270  
330  
25  
7
3000  
4400  
6100  
4700  
4400  
5000  
4700  
7,3 × 4,3  
7,3 × 4,3  
7,3 × 4,3  
10 ×13  
1(3)  
N/R(5)  
N/R(5)  
1(3)  
1(3)  
1(3)  
C 3(2)  
B 2(2)  
B 1(2)  
B 3(2)  
B 4(2)  
B 4(2)  
B 3(2)(7)  
10TPE330MF (VI 8V)  
2R5TPE470M7  
2R5TPD1000M5  
16SEP330M  
5
16  
18  
11  
16  
10 × 11,5  
8 × 13  
16SP270M  
16SEPC270M  
16SVP330M  
10 × 12,6  
1(3)  
(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.  
RoHS, Lead-free and Material Details  
See the 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) Required capacitors with TurboTrans. See the TurboTrans Application information for Capacitor Selection  
Capacitor Types:  
a. Type B = (1,000 < capacitance × ESR 5,000)  
b. Type C = (5,000 < capacitance × ESR 10,000)  
(3) In addition to the required input electrolytic capacitance, 22 µF of ceramic capacitance is recommended to reduce the high-frequency  
reflected ripple current.  
(4) Aluminum Electrolytic capacitor not recommended for the TurboTrans due to higher capacitance × ESR products. Aluminum and higher  
ESR capacitors can be used in conjunction with lower ESR capacitance.  
(5) N/R – Not recommended. The voltage rating does not meet the minimum operating limits.  
(6) The voltage rating of this capacitor only allows it to be used for output voltage that is equal to or less than 80% of the working voltage.  
(7) Total bulk nonceramic capacitors on the output bus with ESR of 15mto 30mrequires an additional 200 µF of ceramic  
capacitance.  
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Table 3. Input/Output Capacitors (continued)  
Capacitor Characteristics  
Quantity  
Output Bus  
Max  
Max  
Ripple  
Capacitor Vendor,  
Type Series (Style)  
Working  
Voltage  
(V)  
ESR  
at 100  
kHz  
Value  
(µF)  
Current  
at 85°C  
(Irms)  
(mA)  
Physical  
Size (mm)  
Input  
Bus  
Vendor Part No.  
TurboTrans  
Cap Type(2)  
(m)  
Kemet, Poly-Tantalum  
T520 (SMD)  
10  
6.3  
4
330  
330  
25  
15  
5
2600  
3800  
7300  
7300  
7,3×4,3×4,1  
7,3×4,3×4,1  
7,3×4,3×4,1  
7,3 × 4,3  
1(8)  
C 3(9)  
B 3(9)  
B 2(9)  
B 1(9)  
T520X337M010ASE025 (VI 8V)  
T530X337M006ASE015  
T530 (SMD)  
N/R(10)  
N/R(10)  
N/R(10)  
T530 (SMD)  
680  
T530X687M004ASE005  
T530 (SMD)  
2.5  
1000  
5
T530X108M2R5ASE005  
Vishay-Sprague  
597D, Tantalum (SMD)  
94SP, OS-CON (Radial)  
94SVP OS-CON(SMD)  
Kemet, Ceramic X5R (SMD)  
Murata, Ceramic X5R  
(SMD)  
16  
16  
16  
16  
25  
16  
16  
16  
220  
270  
330  
10  
40  
18  
17  
2
2300  
4400  
4500  
7,2×5,7×4,1  
10 × 10,5  
10 × 12,7  
3225  
1(8)  
1(8)  
1(8)  
2(8)  
1(8)  
2(8)  
2(8)  
1(8)  
C 5(11)(9)  
B 4(9)  
B 3(9)  
N/R  
597D227X16E2T  
94SP277X0016FBP  
94SVP337X016F12  
C1210C106M4PAC  
GRM32ER61E226K  
GRM32DR61C106K  
C3225X5R1C106MT0  
C3225X5R1C226MT  
22  
2
3225  
N/R  
10  
N/R  
TDK, Ceramic X5R  
(SMD)  
10  
2
3225  
N/R  
22  
N/R  
(8) In addition to the required input electrolytic capacitance, 22 µF of ceramic capacitance is recommended to reduce the high-frequency  
reflected ripple current.  
(9) Required capacitors with TurboTrans. See the TurboTrans Application information for Capacitor Selection  
Capacitor Types:  
a. Type B = (1,000 < capacitance × ESR 5,000)  
b. Type C = (5,000 < capacitance × ESR 10,000)  
(10) N/R – Not recommended. The voltage rating does not meet the minimum operating limits.  
(11) Total bulk nonceramic capacitors on the output bus with ESR of 15mto 30mrequires an additional 200 µF of ceramic  
capacitance.  
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TurboTrans™ Technology  
TurboTrans technology is a feature introduced in the T2 generation of the PTH/PTV family of power modules.  
TurboTrans optimizes the transient response of the regulator with added external capacitance using a single  
external resistor. Benefits of this technology include reduced output capacitance, minimized output voltage  
deviation following a load transient, and enhanced stability when using ultra-low ESR output capacitors. The  
amount of output capacitance required to meet a target output voltage deviation is reduced with TurboTrans  
activated. Likewise, for a given amount of output capacitance, the amplitude of the voltage deviation following a  
load transient is reduced. Applications requiring tight transient voltage tolerances and minimized capacitor  
footprint area benefits greatly from this technology.  
TurboTrans™ Selection  
Utilizing TurboTrans requires connecting a resistor, RTT, between the +Sense pin (pin 6) and the TurboTrans pin  
(pin 9). The value of the resistor directly corresponds to the amount of output capacitance required. All T2  
products require a minimum value of output capacitance. For the PTH08T240F, the minimum required  
capacitance is 1000 µF. Capacitors with a capacitance × ESR product above 1000 µF×mand below 10,000  
µF×mare required. (Multiply the capacitance (in µF) by the ESR (in m) to determine the capacitance × ESR  
product.) See the Capacitor Selection section of the datasheet for a variety of capacitors that meet this criteria.  
Figure 14 thru Figure 21 show the amount of output capacitance required to meet a desired transient voltage  
deviation for Type B (e.g. polymer-tantalum) and Type C (e.g. OS-CON) capacitors. To calculate the proper  
value of RTT, first determine your required transient voltage deviation limits and magnitude of your transient load  
step. Next, determine what type of output capacitors are used. (If more than one type of output capacitor is used,  
select the capacitor type that makes up the majority of your total output capacitance.) Knowing this information,  
use the chart (Figure 14 thru Figure 21) that corresponds to the capacitor type selected. To use the chart, begin  
by dividing the maximum voltage deviation limit (in mV) by the magnitude of your load step (in Amps). This gives  
a mV/A value. Find this value on the Y-axis of the appropriate chart. Read across the graph to the 'TurboTrans'  
plot. From this point, read down to the X-axis which lists the minimum required capacitance, CO, to meet that  
transient voltage deviation. The required RTT resistor value can then be calculated using the equation or selected  
from the TurboTrans table. The TurboTrans tables include both the required output capacitance and the  
corresponding RTT values to meet several values of transient voltage deviation for 25% (2.5 A), 50% (5 A), and  
75% (7.5 A) output load steps.  
The chart can also be used to determine the achievable transient voltage deviation for a given amount of output  
capacitance. By selecting the amount of output capacitance along the X-axis, reading up to the desired  
'TurboTrans'' curve, and then over to the Y-axis, gives the transient voltage deviation limit for that value of output  
capacitance. The required RTT resistor value can be calculated using the equation or selected from the  
TurboTrans table.  
As an example, let's look at a 5-V application requiring a 15-mV deviation during a 3-A load transient. A majority  
of 680-µF, 10-mΩ ouput capacitors will be used. (680 (in µF) × 10 (in mΩ) = 6,800; therefore this is Type C  
capacitance). Use the 5-V, Type C capacitor chart, Figure 19. Dividing 15 mV by 3 A gives 5 mV/A transient  
voltage deviation per amp of transient load step. Select 5 mV/A on the Y-axis and read across to the  
'TurboTrans'' plot. Following this point down to the X-axis gives a minimum required output capacitance of  
approximately 1800 µF. The required RTT resistor value for 1800 µF can then be calculated or selected from  
Table 4. The required RTT resistor is approximately 32.0 k.  
Applications operating from an input bus greater than 8 V may encounter reduced transient performance when  
the output voltage is less than VI/11. Additional output capacitance may be required in order to achieve the  
expected transient performance. See Figure 17 and Figure 21 when operating at an increased VI to VO ratio.  
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PTH08T240F Type B Capacitors  
8-V Input  
5-V Input  
10  
9
10  
9
8
7
8
7
6
5
6
5
4
3
4
3
2
2
1
1
C - Capacitance - mF  
C - Capacitance - mF  
Figure 14. Capacitor Type B,  
1000 < C(µF)×ESR(m) 5000  
(e.g. Polymer-Tantalum)  
Figure 15. Capacitor Type B,  
1000 < C(µF)×ESR(m) 5000  
(e.g. Polymer-Tantalum)  
Table 4. Type B TurboTrans CO Values and Required RTT Selection Table  
Transient Voltage Deviation (mV)  
8-V Input  
5-V Input  
25% load step  
(2.5 A)  
50% load step  
(5 A)  
75% load step  
(7.5 A)  
CO  
Minimum  
RTT  
Required  
CO  
Minimum  
RTT  
Required  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
20  
18  
16  
14  
12  
10  
8
40  
36  
32  
28  
24  
20  
16  
12  
60  
54  
48  
42  
36  
30  
24  
18  
1000  
1040  
1200  
1440  
1760  
2230  
3000  
4350  
open  
866  
1060  
1200  
1400  
1660  
2020  
2550  
3400  
4900  
576  
147  
147  
71.5  
40.2  
23.2  
12.7  
5.36  
0.205  
64.9  
34.0  
18.2  
8.06  
1.54  
6
RTT Resistor Selection  
The TurboTrans resistor value, RTT can be determined from the TurboTrans programming, see Equation 2.  
é
ù
)
û
40´ 1- C 5000  
(
O
ë
R
=
kW  
( )  
TT  
é
ë
ù
C
(
1000 -1  
)
û
O
(2)  
Where CO is the total output capacitance in µF. CO values greater than or equal to 5000 µF require RTT to be a  
short, 0 . (RTT results in a negative value when CO > 5000 µF).  
To ensure stability, the value of RTT must be calculated using the minimum required output capacitance  
determined from the capacitor transient response charts above.  
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PTH08T240F Type B Capacitors (12-V)  
12-V INPUT; VO (VI ÷ 11)  
12-V INPUT; VO < (VI ÷ 11)  
10  
9
10  
9
8
7
8
7
6
5
6
5
4
3
4
3
2
2
1
1
C - Capacitance - mF  
C - Capacitance - mF  
Figure 16. (VO VI ÷ 11)  
Figure 17. VO < (VI ÷ 11)  
Capacitor Type B  
Capacitor Type B  
Table 5. Type B TurboTrans CO Values and Required RTT Selection Table  
Transient Voltage Deviation (mV)  
VO VI/11  
VO < VI/11  
25% load step  
(2.5 A)  
50% load step  
(5 A)  
75% load step  
(7.5 A)  
CO  
Minimum  
RTT  
Required  
CO  
Minimum  
RTT  
Required  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
25  
20  
18  
15  
12  
10  
8
50  
40  
36  
30  
24  
20  
16  
10  
75  
60  
54  
45  
36  
30  
24  
15  
1000  
1000  
1050  
1300  
1760  
2250  
3000  
7900  
open  
open  
634  
1000  
1600  
open  
46.4  
23.7  
8.06  
0.255  
-
2000  
97.6  
34.0  
17.4  
8.06  
short  
3000  
4900  
exceeds max  
exceeds max  
exceeds max  
-
5
-
RTT Resistor Selection  
The TurboTrans resistor value, RTT can be determined from the TurboTrans programming, see Equation 3.  
é
ù
)
û
40´ 1- C 5000  
(
O
ë
R
=
kW  
( )  
TT  
é
ë
ù
C
(
1000 -1  
)
û
O
(3)  
Where CO is the total output capacitance in µF. CO values greater than or equal to 5000 µF require RTT to be a  
short, 0 . (RTT results in a negative value when CO > 5000 µF).  
To ensure stability, the value of RTT must be calculated using the minimum required output capacitance  
determined from the capacitor transient response charts above.  
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PTH08T240F Type C Capacitors  
8-V Input  
5-V Input  
10  
9
10  
9
8
7
8
7
6
5
6
5
4
3
4
3
2
2
1
1
C - Capacitance - mF  
C - Capacitance - mF  
Figure 18. Capacitor Type C,  
5000 < C(µF)×ESR(m) 10,000  
(e.g. OS-CON)  
Figure 19. Capacitor Type C,  
5000 < C(µF)×ESR(m) 10,000  
(e.g. OS-CON)  
Table 6. Type C TurboTrans CO Values and Required RTT Selection Table  
Transient Voltage Deviation (mV)  
8-V Input  
5-V Input  
25% load step  
(2.5 A)  
50% load step  
(5 A)  
75% load step  
(7.5 A)  
CO  
Minimum  
RTT  
Required  
CO  
Minimum  
RTT  
Required  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
20  
18  
16  
14  
12  
10  
8
40  
36  
32  
28  
24  
20  
16  
12  
60  
54  
48  
42  
36  
30  
24  
18  
1000  
1000  
1100  
1300  
1600  
2050  
2750  
4050  
open  
open  
340  
1040  
1180  
1350  
1600  
1930  
2420  
3200  
4560  
787  
169  
82.5  
45.3  
26.7  
14.7  
6.49  
1.0  
97.6  
45.3  
22.6  
10.5  
2.49  
6
RTT Resistor Selection  
The TurboTrans resistor value, RTT can be determined from the TurboTrans programming, see Equation 4 .  
é
ù
)
û
40´ 1- C 5000  
(
O
ë
R
=
kW  
( )  
TT  
é
ë
ù
C
(
1000 -1  
)
û
O
(4)  
Where CO is the total output capacitance in µF. CO values greater than or equal to 5000 µF require RTT to be a  
short, 0 . (RTT results in a negative value when CO > 5000 µF).  
To ensure stability, the value of RTT must be calculated using the minimum required output capacitance  
determined from the capacitor transient response charts above.  
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PTH08T240F Type C Capacitors (12-V)  
12-V INPUT; VO (VI ÷ 11)  
12-V INPUT; VO < (VI ÷ 11)  
10  
9
10  
9
8
7
8
7
6
5
6
5
4
3
4
3
2
2
1
1
C - Capacitance - mF  
C - Capacitance - mF  
Figure 20. VO (VI ÷ 11)  
Figure 21. VO < (VI ÷ 11)  
Capacitor Type C  
Capacitor Type C  
Table 7. Type C TurboTrans CO Values and Required RTT Selection Table  
Transient Voltage Deviation (mV)  
VO VI/11  
VO < VI/11  
25% load step  
(2.5 A)  
50% load step  
(5 A)  
75% load step  
(7.5 A)  
CO  
Minimum  
RTT  
Required  
CO  
Minimum  
RTT  
Required  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
Required Output  
Capacitance (µF)  
TurboTrans  
Resistor (k)  
25  
20  
18  
15  
12  
10  
8
50  
40  
36  
30  
24  
20  
16  
10  
75  
60  
54  
45  
36  
30  
24  
15  
1000  
1000  
1000  
1200  
1600  
2050  
2750  
5400  
open  
open  
open  
150  
1000  
1450  
open  
63.4  
29.4  
9.76  
0.887  
-
1850  
2800  
45.3  
22.6  
10.2  
short  
4600  
exceeds max  
exceeds max  
exceeds max  
-
5
-
RTT Resistor Selection  
The TurboTrans resistor value, RTT can be determined from the TurboTrans programming, see Equation 5.  
é
ù
)
û
40´ 1- C 5000  
(
O
ë
R
=
kW  
( )  
TT  
é
ë
ù
C
(
1000 -1  
)
û
O
(5)  
Where CO is the total output capacitance in µF. CO values greater than or equal to 5000 µF require RTT to be a  
short, 0 . (RTT results in a negative value when CO > 5000 µF).  
To ensure stability, the value of RTT must be calculated using the minimum required output capacitance  
determined from the capacitor transient response charts above.  
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Application Diagram and Waveforms  
TurboTrans  
RTT  
24.3 kW  
10  
9
Track  
TT  
6
5
7
+Sense  
1
SmartSync  
+Sense  
V
V
V
I
I
O
2
PTH08T240F  
V
O
11  
INH/UVLO  
-Sense  
V Adj  
GND  
L
O
A
D
O
+
+
3
4
8
C
O
2000 mF  
Type B  
R
SET  
1%  
0.05 W  
C
I
220 mF  
22 mF  
-Sense  
GND  
GND  
UDG-07126  
Figure 22. Typical TMS320TCI6488 Application  
Without TurboTrans  
50 mV/div  
With TurboTrans  
50 mV/div  
2.5 A/ms  
50% Load Step  
Figure 23. Typical TurboTrans Waveforms (5-V Input)  
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UNDERVOLTAGE LOCKOUT (UVLO)  
The PTH08T240F power modules incorporate an input undervoltage lockout (UVLO). The UVLO feature  
prevents the operation of the module until there is sufficient input voltage to produce a valid output voltage. This  
enables the module to provide a clean, monotonic powerup for the load circuit, and also limits the magnitude of  
current drawn from the regulator’s input source during the power-up sequence.  
The UVLO characteristic is defined by the ON threshold (VTHD) voltage. Below the ON threshold, the Inhibit  
control is overridden, and the module does not produce an output. The hysteresis voltage, which is the difference  
between the ON and OFF threshold voltages, is set at 500 mV. The hysteresis prevents start-up oscillations,  
which can occur if the input voltage droops slightly when the module begins drawing current from the input  
source.  
The UVLO feature of the PTH08T240F module allows for limited adjustment of the ON threshold voltage. The  
adjustment is made via the Inhbit/UVLO Prog control pin (pin 11) using a single resistor (see Figure 24). When  
pin 11 is left open circuit, the ON threshold voltage is internally set to its default value, which is 4.3 V. The ON  
threshold might need to be raised if the module is powered from a tightly regulated 12-V bus. Adjusting the  
threshold prevents the module from operating if the input bus fails to completely rise to its specified regulation  
voltage.  
Equation 6 determines the value of RUVLO required to adjust VTHD to a new value. The default value is 4.3 V, and  
it may only be adjusted to a higher value.  
9690 * ǒ137   VIǓ  
( )  
kW  
R
+
UVLO  
ǒ137   V * 585  
IǓ  
(6)  
Table 8 shows a chart of standard resistor values for RUVLO for different options of the on-threshold (VTHD  
)
voltage.  
Table 8. Standard RUVLO values for Various VTHD values  
VTHD (V)  
5.0  
5.5  
6.0  
6.5  
7.0  
7.5  
8.0  
8.5  
RUVLO (kΩ)  
88.7  
52.3  
37.4  
28.7  
23.2  
19.6  
16.9  
14.7  
V
I
2
V
I
PTH08T240F  
11  
Inhibit/  
UVLO Prog  
+
GND  
4
RUVLO  
C
I
3
GND  
UDG-07127  
Figure 24. Undervoltage Lockout Adjustment Resistor Placement  
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Soft-Start Power Up  
The Auto-Track feature allows the power-up of multiple PTH/PTV modules to be directly controlled from the  
Track pin. However in a stand-alone configuration, or when the Auto-Track feature is not being used, the Track  
pin should be directly connected to the input voltage, VI (see Figure 25).  
When the Track pin is connected to the input voltage the Auto-Track function is permanently disengaged. This  
allows the module to power up entirely under the control of its internal soft-start circuitry. When power up is  
under soft-start control, the output voltage rises to the set-point at a quicker and more linear rate.  
From the moment a valid input voltage is applied, the soft-start control introduces a short time delay (typically  
between 5 ms and 15 ms) before allowing the output voltage to rise.  
10  
V
I
Track  
(2 V/div)  
V
I
2
V
I
PTH08T240F  
V
O
(1 V/div)  
+
GND  
C
I
3
4
GND  
I
I
UDG-07128  
(2 A/div)  
T − Time − 4 ms/div  
Figure 25. Defeating the Auto-Track Function  
Figure 26. Power-Up Waveform  
The output then progressively rises to the module’s setpoint voltage. Figure 26 shows the soft-start power-up  
characteristic of the PTH08T240F operating from a 5-V input bus and configured for a 1.1-V output. The  
waveforms were measured with a 10-A constant current load and the Auto-Track feature disabled. The initial rise  
in input current when the input voltage first starts to rise is the charge current drawn by the input capacitors.  
Power-up is complete within 30 ms.  
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On/Off Inhibit  
For applications requiring output voltage on/off control, the PTH08T240F incorporates an Inhibit control pin. The  
inhibit feature can be used wherever there is a requirement for the output voltage from the regulator to be turned  
off.  
The power modules function normally when the Inhibit pin is left open-circuit, providing a regulated output  
whenever a valid source voltage is connected to VI with respect to GND.  
Figure 27 shows the typical application of the inhibit function. Note the discrete transistor (Q1). The Inhibit input  
has its own internal pull-up. An external pull-up resistor should never be used with the inhibit pin. The input is not  
compatible with TTL logic devices. An open-collector (or open-drain) discrete transistor is recommended for  
control.  
Turning Q1 on applies a low voltage to the Inhibit control pin and disables the output of the module. If Q1 is then  
turned off, the module executes a soft-start power-up sequence. A regulated output voltage is produced within 15  
ms. Figure 28 shows the typical rise in both the output voltage and input current, following the turn-off of Q1. The  
turn off of Q1 corresponds to the rise in the waveform, VINH. The waveforms were measured with a 10-A constant  
current load.  
V
I
2
V
I
I
I
PTH08T240F  
GND  
(2 A/div)  
11  
V
O
(1 V/div)  
+
C
I
3
4
1=Inhibit  
GND  
Q1  
BSS 138  
V
INH  
UDG-07130  
(1 V/div)  
T − Time − 4 ms/div  
Figure 27. On/Off Inhibit Control Circuit  
Figure 28. Power-Up Response from Inhibit Control  
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Overcurrent Protection  
For protection against load faults, all modules incorporate output overcurrent protection. Applying a load that  
exceeds the regulator's overcurrent threshold causes the regulated output to shut down. Following shutdown, the  
module periodically attempts to recover by initiating a soft-start power-up. This is described as a hiccup mode of  
operation, whereby the module continues in a cycle of successive shutdown and power up until the load fault is  
removed. During this period, the average current flowing into the fault is significantly reduced. Once the fault is  
removed, the module automatically recovers and returns to normal operation.  
Overtemperature Protection (OTP)  
A thermal shutdown mechanism protects the module’s internal circuitry against excessively high temperatures. A  
rise in the internal temperature may be the result of a drop in airflow, or a high ambient temperature. If the  
internal temperature exceeds the OTP threshold, the module’s Inhibit control is internally pulled low. This turns  
the output off. The output voltage drops as the external output capacitors are discharged by the load circuit. The  
recovery is automatic, and begins with a soft-start power up. It occurs when the sensed temperature decreases  
by about 10°C below the trip point.  
The overtemperature protection is a last resort mechanism to prevent thermal stress to the regulator.  
Operation at or close to the thermal shutdown temperature is not recommended and reduces the long-term  
reliability of the module. Always operate the regulator within the specified safe operating area (SOA) limits for  
the worst-case conditions of ambient temperature and airflow.  
Differential Output Voltage Remote Sense  
Differential remote sense improves the load regulation performance of the module by allowing it to compensate  
for any IR voltage drop between its output and the load in either the positive or return path. An IR drop is caused  
by the output current flowing through the small amount of pin and trace resistance. With the sense pins  
connected, the difference between the voltage measured directly between the VO and GND pins, and that  
measured at the Sense pins, is the amount of IR drop being compensated by the regulator. This should be  
limited to a maximum of 0.3 V. Connecting the +Sense (pin 6) to the positive load terminal improves the load  
regulation at the connection point. For optimal behavior the –Sense (pin 7) must be connected to GND (pin 4)  
close to the module (within 10 cm).  
If the remote sense feature is not used at the load, connect the +Sense pin to VO (pin 5) and connect the –Sense  
pin to the module GND (pin 4).  
The remote sense feature is not designed to compensate for the forward drop of nonlinear or frequency  
dependent components that may be placed in series with the converter output. Examples include OR-ing  
diodes, filter inductors, ferrite beads, and fuses. When these components are enclosed by the remote sense  
connection they are effectively placed inside the regulation control loop, which can adversely affect the  
stability of the regulator.  
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Smart Sync  
Smart Sync is a feature that allows multiple power modules to be synchronized to a common frequency. Driving  
the Smart Sync pins with an external oscillator set to the desired frequency, synchronizes all connected modules  
to the selected frequency. The synchronization frequency can be higher or lower than the nominal switching  
frequency of the modules within the range between 240 kHz and 400 kHz (see Electrical Specifications table for  
frequency limits). Synchronizing modules powered from the same bus, eliminates beat frequencies reflected back  
to the input supply, and also reduces EMI filtering requirements. Eliminating the low beat frequencies (usually <  
10 kHz) allows the EMI filter to be designed to attenuate only the synchronization frequency. Power modules can  
also be synchronized out of phase to minimize source current loading and minimize input capacitance  
requirements. If unused, connect the Smart Sync pin to GND (pin 3). Figure 29 shows a standard circuit with two  
modules syncronized 180° out-of-phase using a D flip-flop.  
0°  
Track  
Sync  
TurboTrans  
+Sense  
V = 5 V  
I
V
V 1  
I
O
PTH08T220W  
V
O
a
SN74LVC2G74  
Inhibit/  
UVLO  
+
-Sense  
+
V
CC  
C 1  
GND  
V Adj  
O
O
C 1  
I
220 mF  
CLK  
CLK  
D
PRE  
Q
330 mF  
f
= 2 x f  
MOD  
CLK  
GND  
R
SET1  
180°  
GND  
Q
Track  
Sync  
TurboTrans  
+Sense  
V
V 2  
I
O
PTH08T240F  
V
O
Inhibit/  
UVLO  
+
-Sense  
V Adj  
C 2  
I
220 mF  
GND  
+
O
C 2  
O
1000 mF  
R
GND  
SET2  
UDG-07132  
Figure 29. Smart Sync Schematic  
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To achieve the output voltage ripple specified in the electrical characteristics table, the maximum input voltage  
for a given output voltage is limited. The input voltage to output voltage ratio limit is 11 to 1 for the PTH08T240F.  
However, when using SmartSync, the maximum allowable input voltage varies as a function of output voltage  
and switching frequency. Operationally, the maximum input voltage is inversely proportional to switching  
frequency. Synchronizing to a higher frequency causes greater restrictions on the input voltage range. For a  
given switching frequency, Figure 30 shows how the recommended maximum input voltage varies with output  
voltage.  
For example, a module operating at 375 kHz and an output voltage of 0.9 V, the maximum input voltage is 8 V.  
Exceeding the maximum input voltage may cause in an increase in output ripple voltage and increased output  
voltage variation.  
As shown in Figure 30, input voltages below 6 V can operate down to the minimum output voltage over the entire  
synchronization frequency range. See the Electrical Characteristics table for the synchronization frequency range  
and pulse limits.  
RECOMMENDED INPUT VOLTAGE  
vs  
OUTPUT VOLTAGE  
15  
14  
240  
13  
12  
11  
400  
10  
f
(kHz)  
SW  
375  
350  
325  
300  
9
8
275  
250  
240  
250  
275  
300  
325  
350  
375  
400  
7
6
5
0.7  
0.9  
1.1  
V
1.3  
1.5  
1.7  
1.9  
2.1  
- Output Voltage - V  
O
Figure 30.  
Auto-Track™ Function  
The Auto-Track function is unique to the PTH/PTV family, and is available with all POLA products. Auto-Track  
was designed to simplify the amount of circuitry required to make the output voltage from each module power up  
and power down in sequence. The sequencing of two or more supply voltages during power up is a common  
requirement for complex mixed-signal applications that use dual-voltage VLSI devices such as the TMS320™  
DSP family, microprocessors, and ASICs.  
How Auto-Track™ Works  
(1)  
Auto-Track works by forcing the module output voltage to follow a voltage presented at the Track control pin  
.
This control range is limited to between 0 V and the module set-point voltage. Once the track-pin voltage is  
raised above the set-point voltage, the module output remains at its set-point (2). As an example, if the Track pin  
of a 1.5-V regulator is at 1 V, the regulated output is 1 V. If the voltage at the Track pin rises to 3 V, the regulated  
output does not go higher than 1.5 V.  
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When under Auto-Track control, the regulated output from the module follows the voltage at its Track pin on a  
volt-for-volt basis. By connecting the Track pin of a number of these modules together, the output voltages follow  
a common signal during power up and power down. The control signal can be an externally generated master  
ramp waveform, or the output voltage from another power supply circuit (3). For convenience, the Track input  
incorporates an internal RC-charge circuit. This operates off the module input voltage to produce a suitable rising  
waveform at power up.  
Typical Sequencing Application  
The basic implementation of Auto-Track allows for simultaneous voltage sequencing of a number of Auto-Track  
compliant modules. Connecting the Track inputs of two or more modules forces their track input to follow the  
same collective RC-ramp waveform, and allows their power-up sequence to be coordinated from a common  
Track control signal. This can be an open-collector (or open-drain) device, such as a power-up reset voltage  
supervisor IC. See U3 in Figure 31.  
To coordinate a power-up sequence, the Track control must first be pulled to ground potential. This should be  
done at or before input power is applied to the modules. The ground signal should be maintained for at least  
20 ms after input power has been applied. This brief period gives the modules time to complete their internal  
soft-start initialization (4), enabling them to produce an output voltage. A low-cost supply voltage supervisor IC,  
that includes a built-in time delay, is an ideal component for automatically controlling the Track inputs at power  
up.  
Figure 31 shows how the TL7712A supply voltage supervisor IC (U3) can be used to coordinate the sequenced  
power up of PTH08T240F modules. The output of the TL7712A supervisor becomes active above an input  
voltage of 3.6 V, enabling it to assert a ground signal to the common track control well before the input voltage  
has reached the module's undervoltage lockout threshold. The ground signal is maintained until approximately 28  
ms after the input voltage has risen above U3's voltage threshold, which is 4.3 V. The 28-ms time period is  
controlled by the capacitor CT. The value of 2.2 µF provides sufficient time delay for the modules to complete  
their internal soft-start initialization. The output voltage of each module remains at zero until the track control  
voltage is allowed to rise. When U3 removes the ground signal, the track control voltage automatically rises. This  
causes the output voltage of each module to rise simultaneously with the other modules, until each reaches its  
respective set-point voltage.  
Figure 32 shows the output voltage waveforms after input voltage is applied to the circuit. The waveforms, VO1  
and VO2, represent the output voltages from the two power modules, U1 (3.3 V) and U2 (1.8 V), respectively.  
VTRK, VO1, and VO2 are shown rising together to produce the desired simultaneous power-up characteristic.  
The same circuit also provides a power-down sequence. When the input voltage falls below U3's voltage  
threshold, the ground signal is re-applied to the common track control. This pulls the track inputs to 0 V, forcing  
the output of each module to follow, as shown in Figure 33. Power down is normally complete before the input  
voltage has fallen below the modules' undervoltage lockout. This is an important constraint. Once the modules  
recognize that an input voltage is no longer present, their outputs can no longer follow the voltage applied at their  
track input. During a power-down sequence, the fall in the output voltage from the modules is limited by the  
Auto-Track slew rate capability.  
Notes on Use of Auto-Track™  
1. The Track pin voltage must be allowed to rise above the module set-point voltage before the module  
regulates at its adjusted set-point voltage.  
2. The Auto-Track function tracks almost any voltage ramp during power up, and is compatible with ramp  
speeds of up to 1 V/ms.  
3. The absolute maximum voltage that may be applied to the Track pin is the input voltage VI.  
4. The module cannot follow a voltage at its track control input until it has completed its soft-start initialization.  
This takes about 20 ms from the time that a valid voltage has been applied to its input. During this period, it  
is recommended that the Track pin be held at ground potential.  
5. The Auto-Track function is disabled by connecting the Track pin to the input voltage (VI). When Auto-Track is  
disabled, the output voltage rises according to its soft-start rate after input power has been applied.  
6. The Auto-Track pin should never be used to regulate the module's output voltage for long-term, steady-state  
operation.  
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PTH08T240F  
SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
R
1
V
TT  
I
12 V  
AutoTrack  
TurboTrans  
+Sense  
V
I
V
O
SmartSync  
V 1  
O
3.3 V  
U1  
PTH08T240W  
8
V
CC  
+
+
7
2
SENSE  
C
1
I
-Sense  
C 1  
O
RESET  
5
6
RESIN  
Inhibit/UVLO  
V Adj  
GND  
O
U3  
TL7712A  
R
R
1
RESET  
SET  
10 kW  
1
3
REF  
CT  
RESET  
GND  
1.62 kW  
GND  
4
C
C
T
REF  
R
2
TT  
0.1 mF  
2.2 mF  
AutoTrack  
TurboTrans  
+Sense  
V
O
V 2  
O
1.8 V  
U2  
PTH08T240F  
V
I
+
-Sense  
C 2  
O
+
Inhibit/UVLO  
V Adj  
GND  
O
C
I
2
R
2
SET  
4.75 kW  
GND  
UDG-07133  
Figure 31. Sequenced Power Up and Power Down Using Auto-Track  
V
(1 V/div)  
TRK  
V
(1 V/div)  
TRK  
V
1 (1 V/div)  
V
1 (1 V/div)  
2 (1 V/div)  
O
O
V
V
2 (1 V/div)  
O
O
t − Time − 20 ms/div  
t − Time − 400 ms/div  
Figure 32. Simultaneous Power Up  
With Auto-Track Control  
Figure 33. Simultaneous Power Down  
With Auto-Track Control  
28  
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Product Folder Link(s): PTH08T240F  
PTH08T240F  
www.ti.com ........................................................................................................................................ SLTS277CDECEMBER 2006REVISED DECEMBER 2008  
Prebias Startup Capability  
A prebias startup condition occurs as a result of an external voltage being present at the output of a power  
module prior to its output becoming active. This often occurs in complex digital systems when current from  
another power source is backfed through a dual-supply logic component, such as an FPGA or ASIC. Another  
path might be via clamp diodes as part of a dual-supply power-up sequencing arrangement. A prebias can cause  
problems with power modules that incorporate synchronous rectifiers. This is because under most operating  
conditions, these types of modules can sink as well as source output current.  
The PTH family of power modules incorporate synchronous rectifiers, but does not sink current during startup(1),  
or whenever the Inhibit pin is held low. However, to ensure satisfactory operation of this function, certain  
conditions must be maintained(2). Figure 34 shows an application demonstrating the prebias startup capability.  
The startup waveforms are shown in Figure 35. Note that the output current (IO) is negligible until the output  
voltage rises above the voltage backfed through the intrinsic diodes.  
The prebias start-up feature is not compatible with Auto-Track. When the module is under Auto-Track control, it  
sinks current if the output voltage is below that of a back-feeding source. To ensure a pre-bias hold-off one of  
two approaches must be followed when input power is applied to the module. The Auto-Track function must  
either be disabled(3), or the module’s output held off (for at least 50 ms) using the Inhibit pin. Either approach  
ensures that the Track pin voltage is above the set-point voltage at start up.  
1. Startup includes the short delay (approximately 10 ms) prior to the output voltage rising, followed by the rise  
of the output voltage under the module’s internal soft-start control. Startup is complete when the output  
voltage has risen to either the set-point voltage or the voltage at the Track pin, whichever is lowest.  
2. To ensure that the regulator does not sink current when power is first applied (even with a ground signal  
applied to the Inhibit control pin), the input voltage must always be greater than the output voltage throughout  
the power-up and power-down sequence.  
3. The Auto-Track function can be disabled at power up by immediately applying a voltage to the module’s  
Track pin that is greater than its set-point voltage. This can be easily accomplished by connecting the Track  
pin to VI.  
3.3 V  
Track  
+Sense  
V
VI = 5 V  
Vo = 2.5 V  
Io  
V
PTH08T240W  
I
O
Inhibit GND Vadj  
-Sense  
VCCIO  
VCORE  
+
CO  
+
+
R
CI  
SET  
2.37 kW  
ASIC  
Figure 34. PreBias Startup Application Circuit  
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PTH08T240F  
SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
VIN (1 V/div)  
VO (1 V/div)  
IO (2 A/div)  
t - Time - 4 ms/div  
Figure 35. Prebias Startup Waveforms  
30  
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Product Folder Link(s): PTH08T240F  
PTH08T240F  
www.ti.com ........................................................................................................................................ SLTS277CDECEMBER 2006REVISED DECEMBER 2008  
TAPE AND REEL  
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PTH08T240F  
SLTS277CDECEMBER 2006REVISED DECEMBER 2008........................................................................................................................................ www.ti.com  
TRAY  
32  
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Copyright © 2006–2008, Texas Instruments Incorporated  
Product Folder Link(s): PTH08T240F  
PACKAGE OPTION ADDENDUM  
www.ti.com  
8-Dec-2008  
PACKAGING INFORMATION  
Orderable Device  
PTH08T240FAD  
PTH08T240FAS  
PTH08T240FAST  
PTH08T240FAZ  
PTH08T240FAZT  
Status (1)  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
Package Package  
Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)  
Qty  
Type  
Drawing  
DIP MOD  
ULE  
EBS  
11  
11  
11  
11  
11  
49  
Pb-Free  
(RoHS)  
Call TI  
Call TI  
Call TI  
Call TI  
Call TI  
N / A for Pkg Type  
DIP MOD  
ULE  
EBT  
EBT  
BBT  
BBT  
49  
TBD  
Level-1-235C-UNLIM/  
Level-3-260C-168HRS  
DIP MOD  
ULE  
250  
49  
TBD  
Level-1-235C-UNLIM/  
Level-3-260C-168HRS  
DIP MOD  
ULE  
Pb-Free  
(RoHS)  
Level-3-260C-168 HR  
DIP MOD  
ULE  
250  
Pb-Free  
(RoHS)  
Level-3-260C-168 HR  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in  
a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2)  
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check  
http://www.ti.com/productcontent for the latest availability information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements  
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered  
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and  
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS  
compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame  
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)  
(3)  
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder  
temperature.  
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provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the  
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incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited  
information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI  
to Customer on an annual basis.  
Addendum-Page 1  
IMPORTANT NOTICE  
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,  
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