PTH08T220W, PTH08T221W
www.ti.com................................................................................................................................................... SLTS252K – NOVEMBER 2005 – REVISED JUNE 2009
16-A, 4.5-V to 14-V INPUT, NON-ISOLATED,
WIDE-OUTPUT, ADJUSTABLE POWER MODULE WITH TurboTrans™
FEATURES
1
•
•
•
•
•
•
2
•
•
•
•
•
•
•
•
Up to 16-A Output Current
4.5-V to 14-V Input Voltage
Wide-Output Voltage Adjust (0.69 V to 5.5 V)
±1.5% Total Output Voltage Variation
Efficiencies up to 96%
Output Overcurrent Protection
(Nonlatching, Auto-Reset)
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
Ceramic Capacitor Version (PTH08T221W)
POLA™ Compatible
•
•
•
•
TurboTrans™ Technology
Designed to meet Ultra-Fast Transient
Requirements up to 300 A/µs
SmartSync Technology
Auto-Track™ Sequencing
APPLICATIONS
•
•
•
Complex Multi-Voltage Systems
Microprocessors
Bus Drivers
DESCRIPTION
The PTH08T220/221W is a high-performance 16-A rated, non-isolated power module. These modules represent
the 2nd generation of the popular PTH series power modules and include a reduced footprint and improved
features. The PTH08T221W is optimized to be used with all ceramic capacitors.
Operating from an input voltage range of 4.5 V to 14 V, the PTH08T220/221W requires a single resistor to set
the output voltage to any value over the range, 0.69 V to 5.5 V. The wide input voltage range makes the
PTH08T220/221W particularly suitable for advanced computing and server applications that utilize a loosely
regulated 8-V to 12-V intermediate distribution bus. Additionally, the wide input voltage range increases design
flexibility by supporting operation with tightly regulated 5-V, 8-V, or 12-V intermediate bus architectures.
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 PTH08T220/221W includes new patent pending 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. Additionally, for a target
output capacitor bank, TurboTrans can be used to significantly improve the regulators transient response by
reducing the peak voltage deviation. 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
2
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.
TurboTrans, POLA, Auto-Track, 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 © 2005–2009, Texas Instruments Incorporated
PTH08T220W, PTH08T221W
SLTS252K – NOVEMBER 2005 – REVISED JUNE 2009................................................................................................................................................... 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.
PTH08T220W
SmartSync
TurboTranst
Track
10
VI
2
1
Track
SYNC
TT
+Sense
VI
VO
PTH08T220W
Inhibit
11 INH/UVLO
−Sense
GND
GND
VOAdj
3
4
8
+
GND
RUVLO
1%
0.05 W
(Opional)
CI
330 µF
(Required)
RTT
1%
0.05 W
(Optional)
9
CI2
22 µF
(Required)
6
+Sense
5
Vo
7
L
O
A
D
+
CO
220 µF
(Required)
RSET [A]
1%
0.05 W
(Required)
−Sense
GND
UDG−05098
A.
RSET required to set the output voltage to a value higher than 0.69 V. See Electrical Characteristics table.
PTH08T221W - Ceramic Capacitor Version
SmartSync
Track
TurboTranst
10
VI
Track
2
1
SYNC
TT
+Sense
VI
VO
PTH08T221W
Inhibit
11
3
RUVLO
1%
0.05 W
(Opional)
CI
300 µF
(Required)
6
5
VO
−Sense
GND
4
VOAdj
8
L
O
A
D
CO
300 µF
(Required)
RSET [A]
1%
0.05 W
(Required)
−Sense
GND
2
+Sense
7
INH/UVLO
GND
RTT
1%
0.05 W
(Optional)
9
GND
A.
RSET required to set the output voltage to a value higher than 0.69 V. See Electrical Characteristics table.
B.
300 µF of ceramic or 330 µF of electrolytic input capacitance is required for proper operation.
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www.ti.com................................................................................................................................................... SLTS252K – NOVEMBER 2005 – REVISED JUNE 2009
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
PAGE NUMBER
ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS
3
ELECTRICAL CHARACTERISTICS TABLE (PTH08T220W)
4
ELECTRICAL CHARACTERISTICS TABLE (PTH08T221W)
6
TERMINAL FUNCTIONS
8
TYPICAL CHARACTERISTICS (VI = 12V)
9
TYPICAL CHARACTERISTICS (VI = 5V)
10
ADJUSTING THE OUTPUT VOLTAGE
11
INPUT & OUTPUT CAPACITOR RECOMMENDATIONS
13
TURBOTRANS™ INFORMATION
17
UNDERVOLTAGE LOCKOUT (UVLO)
22
SOFT-START POWER-UP
23
OUTPUT INHIBIT
24
OVER-CURRENT PROTECTION
25
OVER-TEMPERATURE PROTECTION
25
REMOTE SENSE
25
SYCHRONIZATION (SMARTSYNC)
26
AUTO-TRACK SEQUENCING
27
PREBIAS START-UP
30
TAPE & REEL AND TRAY DRAWINGS
32
ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS
(Voltages are with respect to GND)
UNIT
Vtrack
Track pin voltage
TA
Operating temperature range Over VI range
Twave
Wave soldering temperature
Surface temperature of module body or pins for
5 seconds maximum.
Treflow
Solder reflow temperature
Surface temperature of module body or pins
Tstg
Storage temperature
Storage temperature of module removed from shipping package
Tpkg
Packaging temperature
Shipping Tray or Tape and Reel storage or bake temperature
45
Mechanical shock
Per Mil-STD-883D, Method 2002.3 1 msec, 1/2
sine, mounted
AH and AD suffix
500
AS and AZ suffix
125
Mechanical vibration
–0.3 to VI + 0.3
AH suffix
AD suffix
Mil-STD-883D, Method 2007.2 20-2000 Hz
Weight
Flammability
(1)
V
–40 to 85
260
AS suffix
235 (1)
AZ suffix
260 (1)
°C
–55 to 125
G
20
5
grams
Meets UL94V-O
During reflow of surface mount package version do not elevate peak temperature of the module, pins or internal components above the
stated maximum.
Copyright © 2005–2009, Texas Instruments Incorporated
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ELECTRICAL CHARACTERISTICS
PTH08T220W
TA = 25°C, VI = 5 V, VO = 3.3 V, CI = 330 µF, CI2 = 22 µF, CO = 220 µF, and IO = IO max (unless otherwise stated)
PARAMETER
TEST CONDITIONS
PTH08T220W
MIN
IO
Output current
Over VO range
25°C, natural convection
Input voltage range
VOADJ
Output voltage adjust range
Over IO range
η
1.2 < VO ≤ 3.6
4.5
14
3.6 < VO ≤ 5.5
VO + 2
14
Over IO range
0.69
±0.3
%Vo
±3
mV
Load regulation
Over IO range
±2
Total output variation
Includes set-point, line, load, –40°C ≤ TA ≤ 85°C
IO = 16 A
95%
RSET = 1.21 kΩ, VO = 3.3 V
94%
RSET = 2.38 kΩ, VO = 2.5 V
91%
RSET = 4.78 kΩ, VO = 1.8 V
88%
(1)
RSET = 20.8 kΩ, VO = 1.0 V
(1)
Overcurrent threshold
Reset, followed by auto-recovery
Transient response
2.5 A/µs load step
50 to 100% IOmax
VO = 2.5 V
w/ TurboTrans
CO= 2000 µF, TypeC
RTT = short
IIL
Track input current (pin 10)
Pin to GND
dVtrack/dt
Track slew rate capability
CO ≤ CO (max)
UVLOADJ
VI increasing, RUVLO = OPEN
Adjustable Under-voltage lockout
VI decreasing, RUVLO = OPEN
(pin 11)
Hysteresis, RUVLO ≤ 52.3 kΩ
82%
(1)
A
Recovery time
70
µs
VO over/undershoot
150
mV
Recovery time
130
µs
VO over/undershoot
30
4.3
3.7
Inhibit (pin 11) to GND, Track (pin 10) open
fs
Switching frequency
Over VI and IO ranges, SmartSync (pin 1) to GND
fSYNC
Synchronization (SYNC)
frequency
VSYNCH
SYNC High-Level Input Voltage
VSYNCL
SYNC Low-Level Input Voltage
tSYNC
SYNC Minimum Pulse Width
CI
External input capacitance
(5)
4
(3)
µA
1
V/ms
4.45
4.2
V
0.5
Open (4)
-0.2
Input low current (IIL ), Pin 11 to GND
Input standby current
mV
–130
Input low voltage (VIL)
Iin
(4)
mVPP
32
Input high voltage (VIH)
Inhibit control (pin 11)
%Vo
84%
15
w/o TurboTrans
CO= 220 µF, TypeC
(2)
87%
RSET = 12.1 kΩ, VO = 1.2 V
20-MHz bandwidth
mV
±1.5
RSET = 171 Ω, VI = 8 V, VO = 5.0 V
VO Ripple (peak-to-peak)
ΔVtrTT
(3)
V
%Vo
Over VI range
ΔVtr
(2)
(2)
–40°C < TA < 85°C
ttr
(1)
±1
V
Line regulaltion
RSET = 7.09 kΩ, VO = 1.5 V
ttrTT
5.5
±0.5
A
(1)
14
Temperature variation
Efficiency
ILIM
16
4.5
Set-point voltage tolerance
VO
UNIT
MAX
0
0.69 ≤ VO ≤ 1.2
VI
TYP
0.8
V
-235
µA
5
mA
300
kHz
240
400
kHz
2
5.5
V
0.8
200
Nonceramic
330
(5)
Ceramic
22
(5)
V
nSec
µF
For output voltages ≤ 1.2 V, at nominal operating frequency, the output ripple may increase (typically 2×) when operating at input
voltages greater than (VO × 11). When using the SmartSync feature to adjust the switching frequency, see the SmartSync
Considerations section of the datasheet for further guidance.
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.
A low-leakage ( 1100 µF.)
To ensure stability, a minimum amount of output capacitance is required for a given RTT resistor value. The value
of RTT must be calculated using the minimum required output capacitance determined from Figure 15 and
Figure 16.
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PTH08T220W Type C Capacitors
12-V INPUT
5-V INPUT
20
20
With TurboTrans
Without TurboTrans
10
9
8
7
Transient − mV/A
6
5
4
3
10
9
8
7
6
5
4
3
VI = 5 V
VI = 12 V
3000
4000
5000
6000
7000
8000
9000
10000
C − Capacitance − µF
2000
300
200
2000
300
3000
4000
5000
6000
7000
8000
9000
10000
2
400
500
600
700
800
900
1000
200
2
400
500
600
700
800
900
1000
Transient − mV/A
With TurboTrans
Without TurboTrans
C − Capacitance − µF
Figure 17. Capacitor Type C,
5000 < C(µF)×ESR(mΩ) ≤ 10,000(e.g. OS-CON)
Figure 18. Capacitor Type C,
5000 < C(µF)×ESR(mΩ) ≤ 10,000(e.g. OS-CON)
Table 6. Type C TurboTrans CO Values and Required RTT Selection Table
Transient Voltage Deviation (mV)
12 Volt Input
5 Volt Input
25% Load
Step
(4 A)
50% Load
Step
(8 A)
75% Load
Step
(12 A)
CO
Minimum Required
Output
Capacitance (µF)
RTT
Required
TurboTrans
Resistor (kΩ)
CO
Minimum Required
Output
Capacitance (µF)
RTT
Required
TurboTrans
Resistor (kΩ)
65
125
190
220
open
220
open
50
100
150
270
274
330
121
40
80
120
330
121
550
34.8
30
60
90
470
48.7
630
26.1
25
50
75
600
28.7
800
16.2
20
40
60
800
16.2
1150
7.15
15
30
45
1300
5.11
1700
1.50
10
20
30
7500
short
10000
short
RTT Resistor Selection
For VO ≤ 3.45V the TurboTrans resistor value, RTT can be determined from the TurboTrans programming
Equation 4. For VO > 3.45 V please contact TI for CO and RTT values.
R TT + 40
ƪ1 * ǒC Oń1980Ǔƫ
ǒ
Ǔ
ǒ5 C OǓ)880
1980
(kW)
*1
(4)
Where CO is the total output capacitance in µF. CO values greater than or equal to 1980 µF require RTT to be a
short, 0Ω. (Equation 4 results in a negative value for RTT when CO > 1980 µF).
To ensure stability, a minimum amount of output capacitance is required for a given RTT resistor value. The value
of RTT must be calculated using the minimum required output capacitance determined from Figure 17 and
Figure 18.
20
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TurboTrans
10
1
VI
AutoTrack
TurboTrans
+Sense
Smart
Sync
2
PTH08T220W
VI
11 Inhibit/
Prog UVLO
3
CI2
22 mF
(Required)
4
6
+Sense
5
VO
VO
−Sense
GND
CI
330 mF
(Required)
RTT
0 kW
9
7
VOAdj
8
L
O
A
D
CO
1220 mF
Type B
RSET
1%
0.05 W
−Sense
GND
GND
Figure 19. Typical TurboTrans™ Application
Without TurboTrans
100 mV/div
With TurboTrans
100 mV/div
2.5 A/ms
50% Load Step
Figure 20. TurboTrans Waveform
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ADJUSTING THE UNDERVOLTAGE LOCKOUT (UVLO)
The PTH08T220/221W 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 PTH08T220/221W 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 21).
When pin 11 is left open circuit, the ON threshold voltage is internally set to its default value, which is 4.3 volts.
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 5 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.
R UVLO +
9690 * ǒ137
ǒ137
VIǓ
VIǓ * 585
(kW)
(5)
Table 7 lists the standard resistor values for RUVLO for different values of the on-threshold (VTHD) voltage.
Table 7. Standard RUVLO values for Various VTHD values
VTHD
5.0 V
RUVLO
5.5 V
6.0 V
6.5 V
7.0 V
7.5 V
8.0 V
8.5 V
9.0 V
9.5 V
10.0 V
10.5 V
11.0 V
88.7 kΩ 52.3 kΩ 37.4 kΩ 28.7 kΩ 23.2 kΩ 19.6 kΩ 16.9 kΩ 14.7 kΩ 13.0 kΩ 11.8 kΩ 10.5 kΩ 9.76 kΩ 8.87 kΩ
PTH08T220W/221W
VI
2
11
VI
Inhibit/UVLO Prog
GND
3
CI
4
RUVLO
GND
Figure 21. Undervoltage Lockout Adjustment Resistor Placement
22
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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 22).
10
Track
VI
2
VI
PTH08T220W/221W
GND
3,4
CI
GND
Figure 22. Defeating the Auto-Track Function
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
2 ms–10 ms) before allowing the output voltage to rise.
VI (5 V/div)
VO (2 V/div)
II (2 A/div)
t − Time − 4 ms/div
Figure 23. Power-Up Waveform
The output then progressively rises to the module’s setpoint voltage. Figure 23 shows the soft-start power-up
characteristic of the PTH08T220/221W operating from a 12-V input bus and configured for a 3.3-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 15 ms.
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On/Off Inhibit
For applications requiring output voltage on/off control, the PTH08T220/221W 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 24 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.
PTH08T220W/221W
2
VI
VI
11
Inhibit/
UVLO
GND
3,4
CI
1 = Inhibit
Q1
BSS 138
GND
Figure 24. On/Off Inhibit Control Circuit
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 25 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.
VO (2 V/div)
II (2 A/div)
VINH (2 V/div)
t − Time − 4 ms/div
Figure 25. Power-Up Response from Inhibit Control
24
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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 0.3V. 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 (pin5) 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 of 240 kHz to 400 kHz. 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
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