TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
D ±1% Reference Over Full Operating
D
D
D
D
D
D
D
D
D
PWP PACKAGE
(TOP VIEW)
Temperature Range
Synchronous Rectifier Driver for >90%
Efficiency
Fixed Output Voltage Options of 1.5 V,
1.8 V, 2.5 V, and 3.3 V
User-Selectable Hysteretic-Type Control
Low Supply Current . . . 3 mA Typ
11.4-V to 13-V Input Voltage Range, VCC
Power Good Output
Programmable Soft-Start
Overvoltage/Overcurrent Protection
Active Deadtime Control
1
2
3
4
5
6
7
8
9
10
11
12
13
14
IOUT
AGND2
OCP
VHYST
VREFB
VSENSE
ANAGND
SLOWST
BIAS
LODRV
LOHIB
DRVGND
LOWDR
DRV
description
28
27
26
25
24
23
22
21
20
19
18
17
16
15
PWRGD
NC
NC
NC
NC
NC
INHIBIT
IOUTLO
LOSENSE
HISENSE
BOOTLO
HIGHDR
BOOT
VCC
NC − No internal connection
The TPS5615 family of synchronous-buck regulator controllers provides an accurate supply voltage to DSPs.
The output voltage is internally set by a resistive divider with an accuracy of 1% over the full operating
temperature range. A hysteretic controller with user-selectable hysteresis is used to dramatically reduce
overshoot and undershoot caused by load transients. Propagation delay from the comparator inputs to the
output drivers is less than 250 ns. Overcurrent shutdown and crossover protection for the output drivers
combine to eliminate destructive faults in the output FETs. PWRGD monitors the output voltage and pulls the
open-collector output low when the output drops below 93% of the nominal output voltage. An overvoltage circuit
disables the output drivers if the output voltage rises 15% above the nominal value. The inhibit pin can be used
to control power sequencing. Inhibit and undervoltage lockout assures that the 12-V supply voltage and system
supply voltage (5 V or 3.3 V) are within proper operating limits before the controller starts. The output driver
circuits include 2-A drivers with internal 8-V gate-voltage regulators that can easily provide sufficient power for
today’s high-powered DSPs. The high-side driver can be configured either as a ground-referenced driver or as
a floating bootstrap driver. The TPS5615 family is available in a 28-pin TSSOP PowerPad™ package. It operates
over a junction temperature range of 0°C to 125°C.
AVAILABLE OPTIONS
PACKAGE
TJ
OUTPUT VOLTAGE
TSSOP†
(PWP)
1.5 V
TPS5615PWP
1.8 V
TPS5618PWP
2.5 V
TPS5625PWP
3.3 V
TPS5633PWP
0°C to 125°C
†
The PWP package is availble taped and reeled. Add R suffix to
device type (e.g., TPS5615PWPR).
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.
PowerPAD is a trademark of Texas Instruments Incorporated.
Copyright © 2000, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
functional block diagram
15
VCC
7
ANAGND
28
20
PWRGD LOSENSE
21
IOUTLO
19
HISENSE
VCC
2V
+
_2X
22
INHIBIT
UVLO
Shutdown
10 V
S
VCC
3
OCP
_
1
IOUT
Q
Fault
Deglitch
+
Rising
Edge
Delay
R
HIGHDR
100mV
HIGHIN
Deglitch
VOVP
1.15 VREF
VPGD
0.93 VREF
VCC
VSENSE
PREREG
Analog
Bias
IVREFB
8
SLOWST
Analog
Bias
9
BIAS
Slowstart
Comparator
+
_
5
14
DRV
DRV REG
Shutdown
16
BOOT
17
HIGHDR
_
Bandgap
Shutdown
CM Filters
+
VREF
18
BOOTLO
+
_
Hysteresis
Comparator
+ _
13
LOWDR
12
DRVGND
Hysteresis
Setting
I VREFB
2
AGND2
2
5
VREFB
4
VHYST
6
VSENSE
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
11
LOHIB
10
LODRV
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
Terminal Functions
TERMINAL
NAME
NO.
I/O
DESCRIPTION
AGND2
2
Analog ground (must be connected).
ANAGND
7
Analog ground
BIAS
9
Analog bias pin. A 1-μF capacitor should be connected from BIAS to ANAGND.
BOOT
16
Bootstrap. A 1-μF capacitor should be connected from BOOT to BOOTLO.
BOOTLO
18
Bootstrap low. Connect to the junction of the high-side and low-side FETs for floating drive configuration.
Connect to PGND for ground-reference drive configuration.
DRV
14
Drive regulator for the FET drivers. A 1-μF capacitor should be connected from DRV to DRVGND.
DRVGND
12
Drive ground. Ground for FET drivers. Connect to FET PWRGND.
HIGHDR
17
High drive. Output drive to high-side power switching FETs.
HISENSE
19
High current sense. For current sensing across high-side FETs, connect to the drain of the high-side FETs;
for optional current sensing scheme, connect to power supply side of current-sense resistor placed in series
with high-side FET drain.
INHIBIT
22
Disables the drive signals to the MOSFET drivers. Also serves as UVLO for system logic supply (3.3 V or
5 V). An external pullup resistor should be connected to system-logic supply.
IOUT
1
Current out. Output voltage on this terminal is proportional to the load current as measured across the
Rds(on) of the high side FET. The voltage on this terminal equals 2 × RDS(ON) × IOUT. In applications where
very accurate current-sensing is required, a sense resistor should be connected between the input supply
and the drain of the high-side FETs.
IOUTLO
21
Current sense low output. This is the voltage on the LOSENSE terminal when the high-side FETs are on.
A ceramic capacitor (between 0.033 μF and 0.1 μF) should be connected from IOUTLO to HISENSE to hold
the sensed voltage.
LODRV
10
Low drive enable. Normally tied to 5 V. To configure the low-side FET as a crowbar, pull LODRV low.
LOHIB
11
Low side inhibit. Connect to the junction of the high- and low-side FETs to control the anti-crossconduction and eliminate shoot-through current. Disabled when configured in crowbar mode.
LOSENSE
20
Low current sense. For current sensing across high-side FETs, connect to the source of the high-side FETs;
for optional current sensing scheme, connect to high-side FET drain side of current-sense resistor placed
in series with high-side FET drain.
13
Low drive. Output drive to synchronous rectifier FETs.
LOWDR
NC
23−27
No connect
OCP
3
Over current protection. Current limit trip point is set with a resistor divider between IOUT and ANAGND.
PWRGD
28
Power good. PWRGD signal goes high when output voltage is within 7% of voltage setpoint. Open-drain
output.
SLOWST
8
Slow Start (soft start). A capacitor form SLOWST to ANAGND sets the slowstart time.
Slowstart current = IVREFB/5
VHYST
4
Hysteresis set input. The hysteresis is set with a resistor divider from VREFB to ANAGND.
Hysteresis = 2 × (VREFB − VHYST)
VCC
15
12-V supply. A 1-μF capacitor should be connected from VCC to DRVGND.
VREFB
5
Buffered reference voltage
VSENSE
6
Voltage sense Input. To be connected from converter output voltage bus to sense and control output voltage.
It is recommended that a RC low-pass filter be connected at this pin to filter noise.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
detailed description
Vref
The reference voltage section consists of a temperature-compensated bandgap reference and a resistive
divider that sets the output voltage option. The output voltage, VREF, is within 1% of the nominal setting over
the full junction temperature range of 0°C to 125°C, and a VCC supply voltage range of 11.4 V to 12.6 V. The
output of the reference network is indirectly brought out through a buffer to the VREFB pin. The voltage on this
pin will be within 2% of VREF. It is not recommended to drive loads with VREFB, other than setting the hysteresis
of the hysteretic comparator, because the current drawn from VREFB sets the charging current for the slowstart
capacitor. Refer to the slowstart section for additional information.
hysteretic comparator
The hysteretic comparator regulates the output voltage of the synchronous-buck converter. The hysteresis is
set by 2 external resistors and is centered on VREF. The 2 external resistors form a resistor divider from VREFB
to ANAGND, with the output voltage connecting to the VHYST pin. The hysteresis of the propagation delay from
the comparator inputs to the driver outputs is 250 ns (maximum). The maximum hysteresis setting is 60 mV.
IO(MAX) = 0.5 μA
VREFB
R1
VHYST
R1 +
R2
2
VH
VREFB–V H
Where
VH = desired hysteresis voltage
TPS56xx
R2
+2
ǒVREFB * VHǓ
Figure 1. Setting the Hysteresis Voltage
low-side driver
The low-side driver is designed to drive low-Rds(on) n-channel MOSFETs. The current rating of the driver is 2
A, source or sink. The bias to the low-side driver is internally connected to the DRV regulator.
high-side driver
The high-side driver is designed to drive low-Rds(on) n-channel MOSFETs. The current rating of the driver is 2
A, source or sink. The high-side driver can be configured either as a ground-referenced driver or as a floating
bootstrap driver. When configured as a floating driver, the bias voltage to the driver is developed from the DRV
regulator. The internal bootstrap diode, connected between the DRV and BOOT pins, is a Schottky for improved
drive efficiency. The maximum voltage that can be applied between BOOT and DRVGND is 30 V. The driver
can be referenced to ground by connecting BOOTLO to DRVGND, and connecting BOOT to either DRV or VCC.
deadtime control
Deadtime control prevents shoot-through current from flowing through the main power FETs during switching
transitions by actively controlling the turn-on times of the MOSFET drivers. The high-side driver is not allowed
to turn on until the gate-drive voltage to the low-side FET is below 2 V; the low-side driver is not allowed to turn
on until the voltage at the junction of the 2 FETs (Vphase) is below 2 V.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
detailed description (continued)
current sensing
Current sensing is achieved by sampling and holding the voltage across the high-side power FET while the
high-side FET is on. The sampling network consists of an internal 60-Ω switch and an external ceramic hold
capacitor. Recommended value of the hold capacitor is between 0.033 μF and 0.1 μF. The actual value should
give a time constant (60 Ω × CH ) greater than the FET on time. Internal logic controls the turn-on and turn-off
of the sample/hold switch such that the switch does not turn on until the Vphase voltage transitions high, and
the switch turns off when the input to the high-side driver goes low. Thus sampling will occur only when the high
side FET is conducting current. The voltage on the IOUT pin equals 2 times the sensed high-side voltage. In
applications where a higher accuracy in current-sensing is required, a sense resistor can be placed in series
with the high-side FET and the voltage across the sense resistor can be sampled by the current sensing circuit.
See Figures 2 and 3.
overcurrent protection
The overcurrent protection (OCP) circuit monitors the current through the high-side FET. The overcurrent
threshold is adjustable with an external resistor divider between IOUT and ANAGND, with the divider voltage
connected to OCP. If the voltage on OCP (VS ) exceeds 100 mV, then a fault latch is set and the output drivers
are turned off. The latch will remain set until VCC goes below the undervoltage lockout value. A 3-μs deglitch
timer is included for noise immunity. The OCP circuit is also designed to protect the high-side power FET against
a short-to-ground fault on the terminal common to both power FETs (Vphase).
RS
VCC
VP
VCC
CH
VP
CH
HIGHDR
R1
LOSENSE
IOUT
HISENSE
2 * VS
IOUTLO
HIGHDR
LOSENSE
VS
HISENSE
IOUTLO
VS
OCP
R2
R2
R1
OCP
TPS56xx
R1 +
2 * VS
IOUT
TPS56xx
ǒVS–0.05Ǔ
R2
R1 +
0.05
Figure 2. OCP Using FET ON-Resistance
R2
ǒVS–0.05Ǔ
0.05
Figure 3. Precision OCP Using External Resistor
inhibit
INHIBIT is a TTL-compatible digital input used to enable the controller. When INHIBIT is low, the output drivers
are low and the slowstart capacitor is discharged. When INHIBIT goes high, the short across the slowstart
capacitor is released and normal converter operation begins. When the system-logic supply is connected to
INHIBIT, it also controls power sequencing by locking out controller operation until the system-logic supply
exceeds the input threshold voltage of the inhibit circuit. Thus the 12-V supply and the system-logic supply
(either 5 V or 3.3 V) must be above UVLO thresholds before the controller is allowed to start up. The INHIBIT
comparator start threshold is 2.1 V and the hysteresis is 100 mV.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
5
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
detailed description (continued)
VCC
To Power Stage
R1
SHUTDOWN
INHIBIT
R2
TPS56xx
R2 + 2.1 R1
V
–2.1
TRIP
Where
VTRIP=desired VSUPPLY trip voltage
Figure 4. Input Undervoltage Lockout Circuit Using INHIBIT
VCC undervoltage lockout (UVLO)
The undervoltage lockout circuit disables the controller while the VCC supply is below the 10-V start threshold
during power up. While the controller is disabled, the output drivers will be low and the slowstart capacitor will
be shorted. When VCC exceeds the start threshold, the short across the slowstart capacitor is released and
normal converter operation begins. There is a 2-V hysteresis in the undervoltage lockout circuit for noise
immunity.
slowstart
The slowstart circuit controls the rate at which VO powers up. A capacitor is connected between SLOWSST and
ANAGND and is charged by an internal current source. The slowstart charging current is determined by the
following equation:
I
SLOWSTART
+
I(VREFB)
5
where I(VREFB) is the current flowing out of VREFB. It is recommended that no additional loads be connected
to VREFB, other than the resistor divider for setting the hysteresis voltage. The maximum current that can be
sourced by the VREFB circuit is 500 μA. The slowstart time is set by:
t
SLOWSTART
+5
C
SLOWST
R
VREFB
where RVREFB is the total external resistance from VREFB to ANAGND.
power good
The power good circuit monitors for an undervoltage condition on VO. If VO is 7% below VREF, then PWRGD
is pulled low. PWRGD is an open-drain output.
overvoltage protection
The overvoltage protection (OVP) circuit monitors VO for an overvoltage condition. If VO is 15% above VREF,
then a fault latch is set and both output drivers are turned off. The latch will remain set until VCC goes below the
undervoltage lockout value. A 3-μs deglitch timer is included for noise immunity. Refer to the LODRV section
for information on how to protect the load against overvoltages due to a shorted fault across the high-side power
FET.
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
detailed description (continued)
drive regulator
The drive regulator provides drive voltage to the output drivers. The minimum drive voltage is 7 V. The minimum
short circuit current is 100 mA. Connect a 1-μF ceramic capacitor from DRV to DRVGND.
LODRV
The LODRV circuit is designed to protect the load against overvoltages that occur if the high-side FETs become
shorted. External components to sense an overvoltage condition are required to use this feature. When an
overvoltage fault occurs, LODRV is pulled low and the low-side FET will be turned on, overriding all control
signals inside the TPS56xx controller. The crowbar action will short the system-logic supply to ground through
the faulted high-side FETs and the low-side FETs. A fuse, in series with VIN, should be added to disconnect the
short circuit.
absolute maximum ratings over operating free-air temperature (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 14 V
Input voltage range: BOOT to DRVGND (high-side driver ON) . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 30 V
BOOT to HIGHDRV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 15 V
BOOT to BOOTLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 15 V
INHIBIT, LODRV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 7.3 V
PWRGD, OCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 7 V
LOHIB, LOSENSE, IOUTLO, HISENSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 14 V
VSENSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to 5 V
Voltage difference between ANAGND and DRVGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.5 V
Output current, VREFB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 mA
Short circuit duration, DRV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Dissipation Rating Table
Operating junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 125°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
Lead temperature soldering 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . 260°C
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: Unless otherwise specified, all voltages are with respect to ANAGND.
DISSIPATION RATING TABLE
PACKAGE
TA ≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
PWP
1150 mW
11.5 mW/°C
630 mW
460 mW
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
7
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
recommended operating conditions
Supply voltage, VCC
MIN
MAX
UNIT
11.4
13
BOOT to DRVGND
0
28
BOOT to BOOTLO
0
13
INHIBIT, LODRV, PWRGD, OCP
0
6
LOHIB, LOSENSE, IOUTLO, HISENSE
0
13
VSENSE
0
4.5
Voltage difference between ANAGND and DRVGND
0
±0.2
V
Output current, VREFB†
0
0.4
mA
Input voltage
†
V
V
Not recommended to load VREFB other than to set hysteresis since IVREFB sets slowstart time.
electrical characteristics over recommended operating virtual junction temperature range,
VCC = 12 V, IDRV = 0 A (unless otherwise noted)
reference
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
TPS5615
1.485
1.515
TPS5618
1.782
1.818
2.475
2.525
VREF
Reference
voltage
VREFB
Output voltage
IREFB = 50 μA
VREFB
Output regulation
10 μA ≤ IO ≤ 500 μA
TPS5625
4 V to 12
6V
VCC = 11
11.4
12.6
TPS5633
3.267
VREF−2%
UNIT
V
3.333
VREF
VREF+2%
2
V
mV
power good
PARAMETER
TEST CONDITIONS
Undervoltage trip threshold
MIN
90
Low-level output voltage, PWRGD
IO = 5 mA
High-level input current, PWRGD
VPWRGD = 6 V
TYP
93
0.5
Hysteresis
MAX
UNIT
95 %VREF
0.75
V
1
μA
10
mV
overvoltage protection
PARAMETER
TEST CONDITIONS
Overvoltage trip threshold
Hysteresis
MIN
TYP
112
115
See Note 2
MAX
UNIT
120 %VREF
10
mV
NOTE 2: Ensured by design, not tested.
slowstart
PARAMETER
TEST CONDITIONS
Charge current
VSLOWST = 0.5 V,
Discharge current
VSOFTST = 1 V
IVREFB = 65 μA
MIN
TYP
MAX
UNIT
10.4
13
15.6
μA
3
Comparator input offset voltage
Comparator input bias current
See Note 2
Hysteresis
10
−7.5
NOTE 2: Ensured by design, not tested.
8
mA
10
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
mV
100
nA
7.5
mV
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
electrical characteristics over recommended operating virtual junction temperature range,
VCC = 12 V, IDRV = 0 A (unless otherwise noted) (continued)
inhibit
PARAMETER
TEST CONDITIONS
Startup threshold
MIN
TYP
MAX
UNIT
1.9
2.1
2.35
V
Hysteresis
0.08
0.1
0.12
V
Stop threshold
1.85
V
input undervoltage lockout
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
9.25
10
10.75
V
Hysteresis
1.9
2
2.2
V
Stop threshold
7.5
Startup threshold
V
hysteretic comparator
PARAMETER
TEST CONDITIONS
Input offset voltage
MIN
TYP
−2.5
Input bias current
See Note 2
Hysteresis accuracy
VREFB − VHYST = 15 mV, (hysteresis window = 30 mV)
Maximum hysteresis setting
VREFB − VHYST = 30 mV
−3.5
MAX
UNIT
2.5
mV
500
nA
3.5
mV
60
mV
NOTE 2: Ensured by design, not tested.
overcurrent protection
PARAMETER
TEST CONDITIONS
OCP trip threshold
Input bias current
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
MIN
TYP
MAX
90
100
110
UNIT
mV
100
nA
9
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
electrical characteristics over recommended operating virtual junction temperature range,
VCC = 12 V, IDRV = 0 A (unless otherwise noted) (continued)
high-side VDS sensing
PARAMETER
TEST CONDITIONS
MIN
Gain
TYP
MAX
2
UNIT
V/V
Initial accuracy
VHISENSE = 12 V,
VLOSENSE = 11.9 V
Differential input to Vds sensing amp = 100 mV
IOUTLO sink current
5 V ≤ VIOUTLO ≤ 13 V
IOUT source current
VIOUT = 0.5 V,
VIOUTLO = 11.5 V
VHISENSE = 12 V,
500
μA
IOUT sink current
VIOUT = 0.05 V,
VIOUTLO = 12 V
VHISENSE = 12 V,
50
μA
Output voltage swing
VHISENSE = 4.5 V
VHISENSE = 11 V
RIOUT = 10 kΩ
VHISENSE = 3 V
LOSENSE high-level input voltage
VHISENSE = 4.5 V,
See Note 2
LOSENSE low-level input voltage
VHISENSE = 4.5 V,
See Note 2
Sample/hold resistance
CMRR
194
206
mV
250
nA
0
2
0
1.5
0
0.75
2.85
V
V
2.4
11.4 V ≤ VHISENSE ≤ 12.6 V,
LOSENSE connected to HISENSE,
VHISENSE − VIOUTLO = 0.15 V
50
60
80
4.5 V ≤ VHISENSE ≤ 5.5 V,
LOSENSE connected to HISENSE,
VHISENSE − VIOUTLO = 0.15 V
62
85
123
3 V ≤ VHISENSE ≤ 3.6 V,
LOSENSE connected to HISENSE,
VHISENSE − VIOUTLO = 0.15 V
67
95
144
VHISENSE = 12.6 V to 3 V,
VHISENSE − VOUTLO = 100 mV
69
75
MIN
TYP
V
Ω
dB
NOTE 2: Ensured by design, not tested.
deadtime
PARAMETER
LOHIB
LODR
LOHIB
LODR
High level input voltage
High-level
Low level input voltage
Low-level
TEST CONDITIONS
See Note 2
2.4
See Note 2
3
MAX
UNIT
V
See Note 2
1.4
See Note 2
1.7
V
NOTE 2: Ensured by design, not tested.
LODRV
PARAMETER
TEST CONDITIONS
High-level input voltage
LODRV
MIN
TYP
MAX
1.85
UNIT
V
Low-level input voltage
0.95
V
MAX
UNIT
drive regulator
PARAMETER
TEST CONDITIONS
Output voltage
11.4 V ≤ VCC ≤ 12.6 V,
Output regulation
1 mA ≤ IDRV ≤ 500 mA
IDRV = 50 mA
Short-circuit current
10
MIN
• DALLAS, TEXAS 75265
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100
100
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TYP
7
V
mV
mA
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
electrical characteristics over recommended operating virtual junction temperature range,
VCC = 12 V, IDRV = 0 A (unless otherwise noted) (continued)
bias regulator
PARAMETER
TEST CONDITIONS
11.4 V ≤ VCC ≤ 12.6 V,
Output voltage
See Note 3
MIN
TYP
MAX
6
UNIT
V
NOTE 3: The bias regulator is designed to provide a quiet bias supply for the TPS56xx controller. External loads should not be driven by the bias
regulator.
output drivers
PARAMETER (see Note 4)
TEST CONDITIONS
High-side sink
High-side source
Peak output current
Low-side sink
Low-side source
High-side sink
High-side source
Output resistance
Low-side sink
Low-side source
MIN
Duty cycle < 2%, tpw < 100 μs, TJ = 125°C,
VBOOT − VBOOTLO = 6.5
6 5 V,
V
VHIGHDR = 1.5 V (SRC) or 5 V (sink), See Note 2
2
Duty cycle < 2%, tpw < 100 μs, TJ = 125°C,
VDRV = 6
6.5
5V
V, VLOWDR = 1.5
1 5 V (SRC) or 5 V
(sink), See Note 2
2
TYP
MAX
UNIT
2
A
2
3
TJ = 125
125°C,
C, VBOOT − VBOOTLO = 6.5 V,
VHIGHDR = 1.5 V (SRC) or 5 V (sink)
45
5.7
TJ = 125
125°C,
C, VDRV = 6.5 V,
VLOWDR = 1.5 V (SRC) or 5 V (sink)
Ω
45
NOTES: 2. Ensured by design, not tested.
4. The pull up/down circuits of the drivers are bipolar and MOSFET transistors in parallel. The peak output current rating is the
combined current from the bipolar and MOSFET transistors. The output resistance is the RDS(ON) of the MOSFET transistor when
the voltage on the driver output is less than the saturation voltage of the bipolar transistor.
supply current
PARAMETER
TEST CONDITIONS
VCC supply voltage range
VCC quiescent current
MIN
TYP
MAX
11.4
12
13
10
VINHIBIT = 5 V,
VBOOTLO = 0 V,
VCC > 10.75 V at startup,
See Note 2
3
VINHIBIT = 5 V,
VBOOTLO = 0 V,
CLOWDR = 50 pF,
VCC > 10.75 V at startup,
CHIGHDR = 50 pF,
fswx = 200 kHz
5
VINHIBIT = 5 V,
VBOOT = 13 V,
CHIGHDR = 50 pF,
VCC > 10.75 V at startup,
VBOOTLO = 0 V,
fswx = 200 kHz
V
mA
VINHIBIT = 0 V or VCC < 9.25 V at startup,
VBOOT = 13 V, VBOOTLO = 0 V
High-side drive regulator quiescent current
UNIT
80
2
μA
mA
NOTE 2: Ensured by design, not tested.
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
switching characteristics over recommended operating virtual junction temperature range,
VCC = 12 V, IDRV = 0 V (unless otherwise noted)
PARAMETER
P
Propagation
ti d
delay
l
TEST CONDITIONS
MAX
UNIT
150
250
ns
OCP comparator
See Note 2
1
OVP comparator
See Note 2
1
PWRGD comparator
See Note 2
1
SLOWST comparator
Overdrive = 10 mV (see Note 2)
HIGHDR output
CL = 9 nF,
VBOOTLO = 0 V,
VBOOT = 6.5 V,
TJ = 125°C
LOWDR output
CL = 9 nF,
TJ = 125°C
VDRV = 6.5 V,
HIGHDR output
CL = 9 nF,
VBOOTLO = 0 V,
VBOOT = 6.5 V,
TJ = 125°C
LOWDR output
CL = 9 nF,
TJ = 125°C
VDRV = 6.5 V,
OCP
See Note 2
2
5
OVP
See Note 2
2
5
Fall time
Response time
TYP
Overdrive = 10 mV (see Note 2)
Rise time
Deglitch time (includes
comparator propagation
delay)
MIN
VSENSE to HIGHDR or
LOWDR (excluding deadtime)
High-side VDS sensing
560
μs
900
60
ns
60
60
ns
60
VHISENSE = 12 V,
VIOUTLO pulsed from 12 V to 11.9 V,
100 ns rise/fall times, See Note 2
2
VHISENSE = 4.5 V,
VIOUTLO pulsed from 4.5 V to 4.4 V,
100 ns rise/fall times, See Note 2
3
VHISENSE = 3 V,
VIOUTLO pulsed from 3 V to 2.9 V,
100 ns rise/fall times, See Note 2
3
Short-circuit protection risingedge delay
SCP
LOSENSE = 0 V,
Turn-on/turn-off delay
VDS sensing sample/hold
switch
Crossover delay time
(see Note 2)
ns
μss
μs
300
500
ns
3 V ≤ VHISENSE ≤ 11 V,
VLOSENSE = VHISENSE
(see Note 2)
30
100
ns
LOWDR to HIGHDRV, and
LOHIB to LOWDR
See Note 2
30
100
ns
Prefilter pole frequency
Hysteretic comparator
See Note 2
Propagation delay
LODRV
See Note 2
NOTE 2: Ensured by design, not tested.
12
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5
MHz
400
ns
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
TYPICAL CHARACTERISTICS
SLOWSTART TIMING
vs
CAPACITANCE
1000
10
VREFB = 2 V
I(VREFB) = 100μA
C(SLOWST) = 0.1 μF
TJ = 25°C
VREFB = 2 V
C(SLOWST) = 0.1μF
TJ = 25°C
SLOWSTART Timing − ms
SLOWSTART Time − ms
100
SLOWSTART TIMING
vs
VREFB CURRENT
1
0.1
0
0.0001
0.001
0.01
0.1
100
10
1
1
1
Capacitance − μF
Figure 5
t f − Output Driver Fall Time − ns
t r − Output Driver Rise Time − ns
High Side Driver
10
Low Side Driver
1
1
1000
OUTPUT DRIVER FALL TIME
vs
LOAD CAPACITANCE
1000
0.1
100
Figure 6
OUTPUT DRIVER RISE TIME
vs
LOAD CAPACITANCE
100
10
I(VREFB) − VREFB Current − μA
10
100
100
High Side Driver
10
Low Side Driver
1
0.1
CL − Load Capacitance − nF
1
10
100
CL − Load Capacitance − nF
Figure 7
Figure 8
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
TYPICAL CHARACTERISTICS
OCP THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
OVP THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
105
118
OCP Threshold Voltage − mV
OVP Threshold Voltage − %
117
116
115
114
103
101
99
97
113
95
112
0
25
50
75
100
0
125
25
100
125
Figure 10
Figure 9
INHIBIT HYSTERESIS VOLTAGE
vs
JUNCTION TEMPERATURE
INHIBIT START THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
150
INHIBIT Hysteresis Voltage − mV
2.1
INHIBIT Start Threshold Voltage − V
75
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
2.05
2
1.95
125
100
75
50
1.90
0
25
50
75
100
125
0
25
50
Figure 12
Figure 11
POST OFFICE BOX 655303
75
100
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
14
50
• DALLAS, TEXAS 75265
125
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
TYPICAL CHARACTERISTICS
UVLO HYSTERESIS VOLTAGE (VCC)
vs
JUNCTION TEMPERATURE
UVLO START THRESHOLD VOLTAGE VCC
vs
JUNCTION TEMPERATURE
2.5
UVLO Hysteresis Voltage ( VCC ) − V
UVLO Start Threshold Voltage ( VCC ) − V
10.5
10
9.5
2.3
2.1
1.9
1.7
1.5
9
0
25
50
75
100
0
125
25
75
100
125
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
Figure 14
Figure 13
PWRGD THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
QUIESCENT CURRENT VCC
vs
JUNCTION TEMPERATURE
95
PWRGD Threshold Voltage − % Vo
6
Quiescent Current ( VCC ) − mA
50
4
2
94
93
92
91
90
0
0
25
50
75
100
125
0
25
50
75
100
125
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
Figure 16
Figure 15
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
TYPICAL CHARACTERISTICS
VDS SAMPLE/HOLD RESISTANCE
vs
JUNCTION TEMPERATURE
SLOWSTART CHARGE CURRENT
vs
JUNCTION TEMPERATURE
100
VDS Sample/Hold Resistance − Ω
Slowstart Charge Current − μ A
15
14
13
12
11
75
50
25
0
10
0
25
50
75
100
0
125
25
50
Figure 18
Figure 17
DRIVE REGULATOR LOAD REGULATION
vs
JUNCTION TEMPERATURE
DRIVE REGULATOR OUTPUT VOLTAGE
vs
JUNCTION TEMPERATURE
175
Drive Regulator Load Regulation − mV
8.5
Vo − Drive Regulator Output Voltage − V
125
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
8.25
8
7.75
150
125
100
7.5
0
25
50
75
100
125
0
25
50
Figure 20
Figure 19
POST OFFICE BOX 655303
75
100
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
16
100
75
• DALLAS, TEXAS 75265
125
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
TYPICAL CHARACTERISTICS
HIGH−SIDE DRIVER OUTPUT RESISTANCE
vs
JUNCTION TEMPERATURE
DRIVE REGULATOR LINE REGULATION
vs
JUNCTION TEMPERATURE
5
High−Side Driver Output Resistance − Ω
150
125
4
3
2
1
0
100
0
25
50
75
100
0
125
25
50
75
100
125
TJ − Junction Temperature − °C
TJ − Junction Temperature − °C
Figure 22
Figure 21
LOW−SIDE DRIVER OUTPUT RESISTANCE
vs
JUNCTION TEMPERATURE
6
Low−Side Driver Output Resistance −Ω
Drive Regulator Line Regulation − mV
175
5
4
3
2
1
0
0
25
50
75
100
125
TJ − Junction Temperature − °C
Figure 23
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17
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
APPLICATION INFORMATION
Synchronous rectifier buck regulator circuits are used where high efficiency and low dropout voltages are required.
The TPS56xx controller is useful in applications with very high transient loads and wide dc load ranges, such as
multiple-DSP applications.
The circuit below will meet a wide variety of applications with maximum continuous-rated output currents of up to 8 A.
Design tradeoffs, such as cost, size, or efficiency may need to be addressed for specific applications. Care should
be taken in the proper layout (see last section of this data sheet for specific layout guidelines), especially in the
higher-current configurations, to ensure that noise and ripple are kept to a minimum. Basic layout considerations are
discussed in the 1996 Power Supply Circuits Databook (Literature no. SLVD002). Design guidelines and equations
are discussed in Synchronous Buck Converter Design Using TPS56xx Controllers in SLVP10x EVMs User’s Guide
(Literature no. SLVU007).
18
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
J1−6
J1−5
Vin
RETURN
J1−9
J1−10
J1−7
PG
+12 V
J1−8
R6
1.3 kΩ
C1
22 μF
10 V
C14
0.01 μF
C12 0.1 μF
R12
20.0 kΩ 1%
U1
TPS5625
R9
100 Ω 1%
C15 1000 pF
R13
C16 0.1 μF
C17 1 μF
Analog GND
J1−3
J1−1
R11
750 Ω
SD
R7
11.0 kΩ 1%
PwrGND
APPLICATION INFORMATION
C11
1 μF
R8
100 Ω
1%
R1
1.0 kΩ
1
IOUT
PWRGD
28
2
3
AGND2
OCP
NC
NC
27
26
4
VHYST
NC
25
5
VREFB
NC
24
6
7
VSENSE
ANAGND
NC
INHIBIT
23
22
8
SLOWST
9
BIAS
IOUTLO
21
LOSENSE
20
10
LODRV
HISENSE
19
11
LOHIB
BOOTLO
18
12
DRVGND
HIGHDR
17
13
14
LOWDR
DRV
BOOT
VCC
16
15
R2
10 kΩ
C3 0.1 μF
C2
0.1 μF
C4
1 μF
R17
1 MΩ
C7 1 μF
R4
10 Ω
C18
0.1 μF
R3
10 Ω
Q2
Si4410
L1
2.2 μH
Q1
Si4410
C5 2.2 μF
R16
4.7 Ω
Power GND
C6 680 μF 6.3 V
C8 0.01 μF
R5
2.7 Ω
L2
2.6 μH
See Note A
L1 = 10T #22 on T30−18 Core
L2 = 12T #20 on T44−8Core
C9 820 μF 4V
C10 10 μF
Not Used:
R10, R13, R14
C13
J1−15
J1−16
J1−18
J1−17
2.5 V
8A
J1−2
J1−4
VsenseH
VsenseL/
AnaGND
J1−11
J1−12
J1−14
PwrGND J1−13
R15
4.7 Ω
NOTE A: Theses two traces should be physically close to each other for good noise immunity.
Figure 24. Typical Design Schematic
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SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
Table 1. Test Results for 2.5-V, 8-A Converter
TEST
CONDITIONS
Output voltage
VIN = 5.25 V,
IO = 8 A
Load regulation
VIN = 5.25 V,
Line regulation
Ripple
Efficiency
QTY
UNITS
2.50
V
IO = 0.8 to 8 A
0.4
%
IO =6 A,
VCC = 4.5 V to 6 V
0.2
%
VIN = 5.25 V,
IO = 8 A
50
mVpp
VIN = 5.25 V,
IO = 8 A
89
%
Table 2. 2.5-V, 8-A Converter Bill of Materials
REF DES
QTY
DESCRIPTION
MFG
1
10SS22M
Capacitor, Os-Con, 22 μF, 10 V, 20%
Sanyo
C2
4
GRM39X7R104K016A
Capacitor, Ceramic, 0.1 μF, 16 V, 10%, X7R
muRata
GRM39X7R104K016A
Capacitor, Ceramic, 0.1 μF, 16 V, 10%, X7R
muRata
C3
C4
4
GRM42-6Y5V105Z016A
Capacitor, Ceramic, 1 μF, 16 V, +80%−20%
muRata
C5
1
GRM42-6Y5V225Z016A
Capacitor, Os-Con, 2.2 μF, 16 V, Y5U
muRata
C6
1
6SP680M
Capacitor, Os-Con, 680 μF, 6.3 V, 20%
Sanyo
GRM42-6Y5V105Z016A
Capacitor, Ceramic, 1 μF, 16 V, +80%−20%
muRata
C8
2
GRM39X7R103K025A
Capacitor, Ceramic, 0.01 μF, 25 V, 10%, X7R
muRata
C9
1
4SP820M
Capacitor, Os-Con, 820 μF, 4 V, 20%
Sanyo
C10
1
GRM235Y5V106Z016A
Capacitor, Ceramic, 10 μF, 16 V, Y5V
muRata
C11
GRM42-6Y5V105Z016A
Capacitor, Ceramic, 1 μF, 16 V, +80%−20%
muRata
C12
GRM39X7R104K016A
Capacitor, Ceramic, 0.1 μF, 16 V, 10%, X7R
muRata
C14
GRM39X7R103K025A
Capacitor, Ceramic, 0.01 μF, 25 V, 10%, X7R
muRata
GRM39X7R102K050A
Capacitor, Ceramic, 1000 pF, 50 V, 10%, X7R
muRata
C16
GRM39X7R104K016A
Capacitor, Ceramic, 0.1 μF, 16 V, 10%, X7R
muRata
C17
GRM42-6Y5V105Z016A
Capacitor, Ceramic, 1 μF, 16 V, +80%−20%
muRata
GRM39X7R104K016A
Capacitor, Ceramic, 0.1 μF, 16 V, 10%, X7R
muRata
S1122-18-ND
Header, RA, 18-pin, 0.23 Posts × 0.20 Tails
Sullins
C7
C15
1
C18
J1
1
L1
1
L2
1
Q1
2
Q2
Inductor, Filter, 2.2 μH, 8.5 A (10T #22 on T30-18 Core)
Inductor, Filter, 2.6 μH, 8.5 A (12T #20 on T44-8 Core)
Si4410DY
FET, N-ch, 30-V, 10-A, 13-mΩ
Siliconix
Siliconix
Si4410DY
FET, N-ch, 30-V, 10-A, 13-mΩ
R1
3
Std
Resistor, Chip, 1.0 kΩ, 1/16W, 5%
R2
1
Std
Resistor, Chip, 10 kΩ, 1/16W, 5%
R3
2
Std
Resistor, Chip, 10 Ω, 1/10W, 5%
Std
Resistor, Chip, 10 Ω, 1/10W, 5%
Std
Resistor, Chip, 2.7 Ω, 1/4W, 5%
Std
Resistor, Chip, 1.3 kΩ, 1/16W, 5%
R4
R5
1
R6
R7
1
Std
Resistor, Chip, 11.0 kΩ, 1/16W, 1%
R8
2
Std
Resistor, Chip, 100 Ω, 1/16W, 1%
Std
Resistor, Chip, 100 Ω, 1/16W, 1%
R9
Std
Resistor, Chip, 750 Ω, 1/16W, 5%
R12
1
Std
Resistor, Chip, 20.0 kΩ, 1/16W, 1%
R15
2
Std
Resistor, Chip, 4.7 Ω, 1/16W, 5%
Std
Resistor, Chip, 4.7 Ω, 1/16W, 5%
R11
R16
20
PART NUMBER
C1
R17
1
Std
Resistor, Chip, 1 MΩ, 1/16W, 5%
U1
1
TPS5625PWP
IC, PWM Ripple Controller, FIxed 2.5 V
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TI
TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
APPLICATION INFORMATION
EFFICIENCY
vs
OUTPUT CURRENT
100
Efficiency − %
95
90
85
80
0
1
2
3
4
5
6
7
8
Output Current − A
Figure 25
Top: Vo 10 mV/div
Bottom: VDS Q2 5 V/div
2 μs/div
Figure 26. Output Voltage Ripple at 8 A
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
APPLICATION INFORMATION
20 μs/div
IO
2.5 A/div
VO
20 mV/div
Figure 27. Rising Load Transient Response
IO
2.5 A/div
20 μs/div
VO
20 mV/div
Figure 28. Falling Load Transient Response
22
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TPS5615, TPS5618, TPS5625, TPS5633
SYNCHRONOUS-BUCK HYSTERETIC REGULATOR CONTROLLER
SLVS177B − SEPTEMBER 1998 − REVISED JULY 2000
APPLICATION INFORMATION
layout guidelines
Good power supply results will only occur when care is given to proper design and layout. Layout will affect noise
pickup and generation and can cause a good design to perform with less than expected results. With a range
of currents from milliamps to tens or even hundreds of amps, good power supply layout is much more difficult
than most general PCB design. The general design should proceed from the switching node to the output, then
back to the driver section and, finally, place the low-level components. Below are several specific points to
consider before layout of a TPS56xx design begins.
1. All sensitive analog components should be referenced to ANAGND. These include components connected
to SLOWST, IOUT, OCP, VSENSE, VREFB, VHYST, BIAS, and LOHIB.
2. Analog ground and drive ground should be isolated as much as possible. Ideally, analog ground will connect
to the ground side of the bulk storage capacitors, on VO, and drive ground will connect to the main ground
plane close to the source of the low-side FET.
3. Connections from the drivers to the gate of the power FETs should be as short and wide as possible to
reduce stray inductance. This becomes more critical if external gate resistors are not being used.
4. The bypass capacitor for the DRV regulator should be placed close to the TPS56xx and be connected to
DRVGND.
5. The bypass capacitor for VCC should be placed close to the TPS56xx and be connected to DRVGND.
6. When configuring the high-side driver as a floating driver, the connection from BOOTLO to the power FETs
should be as short and as wide as possible. The other pins that also connect to the power FETs, LOHIB
and LOSENSE, should have a separate connection to the FETs, since BOOTLO will have large peak
currents flowing through it.
7. When configuring the high-side driver as a floating driver, the bootstrap capacitor (connected from BOOT
to BOOTLO) should be placed close to the TPS56xx.
8. When configuring the high-side driver as a ground referenced driver, BOOTLO should be connected to
DRVGND.
9. The bulk storage capacitors across VI should be placed close to the power FETs. High-frequency bypass
capacitors should be placed in parallel with the bulk capacitors and connected close to the drain of the
high-side FET and close to the source of the low-side FET.
10. High-frequency bypass capacitors should be placed across the bulk storage capacitors on VO.
11. HISENSE and LOSENSE should be connected very close to the drain and source, respectively, of the
high-side FET. HISENSE and LOSENSE should be routed very close to each other to minimize
differential-mode noise coupling to these traces.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
23
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
TPS5618PWP
ACTIVE
HTSSOP
PWP
28
50
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
TPS5618
TPS5633PWP
ACTIVE
HTSSOP
PWP
28
50
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
TPS5633
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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