Texas Instruments TPS5210PWPR, TPS5210PWP, TPS5210EVM-126, TPS5210EVM-119, TPS5210EVM-116 Datasheet

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TPS5210
PROGRAMMABLE SYNCHRONOUS-BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
1
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
D
±1% Reference Over Full Operating T emperature Range
D
Synchronous Rectifier Driver for Greater Than 90% Efficiency
D
Programmable Reference V oltage Range of
1.3 V to 3.5 V
D
User–Selectable Hysteretic T ype Control
D
Droop Compensation for Improved Load Transient Regulation
D
Adjustable Overcurrent Protection
D
Programmable Softstart
D
Overvoltage Protection
D
Active Deadtime Control
D
Power Good Output
D
Internal Bootstrap Schottky Diode
D
Low Supply Current...3-mA Typ
description
The TPS5210 is a synchronous-buck regulator controller which provides an accurate, programmable supply voltage to microprocessors. An internal 5-bit DAC is used to program the reference voltage to within a range of 1.3 V to 3.5 V . The output voltage can be set to be equal to the reference voltage or to some multiple of the reference voltage. A hysteretic controller with user-selectable hysteresis and programmable droop compensation 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 FET s. The softstart current source is proportional to the reference voltage, thereby eliminating variation of the softstart timing when changes are made to the output voltage. PWRGD monitors the output voltage and pulls the open-collector output low when the output drops 7% below 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 the 12-V supply voltage and system supply voltage (5 V or 3.3 V) are within proper operating limits before the controller starts. Single-supply (12 V) operation is easily accomplished using a low-current divider for the required 5-V signals. The output driver circuits include 2-A drivers with internal 8-V gate-voltage regulators. The high-side driver can be configured either as a ground-referenced driver or as a floating bootstrap driver. The TPS5210 is available in a 28-pin SOIC package and a 28-pin TSSOP PowerPAD package. It operates over a junction temperature range of 0°C to 125°C.
AVAILABLE OPTIONS
PACKAGES
T
J
SOIC (DW)
TSSOP
(PWP)
0°C to 125°C TPS5210DW TPS5210PWPR
The DW package is available taped and reeled. Add R suffix to device type (e.g., TPS5210DWR).
Copyright 1999, 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.
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.
1 2 3 4 5 6 7 8 9 10 11 12 13 14
28 27 26 25 24 23 22 21 20 19 18 17 16 15
IOUT
DROOP
OCP VHYST VREFB
VSENSE ANAGND SLOWST
BIAS
LODRV
LOHIB
DRVGND
LOWDR
DRV
PWRGD VID0 VID1 VID2 VID3 VID4 INHIBIT IOUTLO LOSENSE HISENSE BOOTLO HIGHDR BOOT V
CC
DW OR PWP PACKAGE
(TOP VIEW)
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
2
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
11111
Decode
VID0 VID1 VID2 VID3 VID4
SQ
R
Deglitch
Deglitch
100 mV
+
V
OVP
1.15 V
ref
V
PGD
0.93 V
ref
Rising
Edge
Delay
+
+
PREREG
DRV REG
+
+
Hysteresis
Setting
+
VID
MUX
and
Decoder
2x
SLOWST
OCP
INHIBIT
Bandgap Shutdown
I
VREFB
5
Shutdown
VSENSE
HIGHIN
HIGHDR
V
CC
Analog Bias
Analog Bias
Slowstart Comp
Hysteresis Comp
CM Filters
VREF
+
Σ
28 20 21 1915 7
V
CC
ANAGND PWRGD LOSENSE IOUTLO HISENSE
2 V
10 V
V
CC
UVLO
NOCPU
Fault
Shutdown
IOUT
BIAS DRV
BOOT HIGHDR
BOOTLO
LOWDR DRVGND
1
9 14
16 17
18
13 12
6
11 1042523
VID0 VID1 VID2 VID3 VID4
24252627
VREFB DROOP VHYST VSENSE LOHIB LODRV
8
3
22
I
VREFB
200 k
200 k
functional block diagram
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
3
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Terminal Functions
TERMINAL
NAME NO.
I/O
DESCRIPTION
ANAGND 7 Analog ground BIAS 9 O Analog BIAS pin. A 1-µF ceramic capacitor should be connected from BIAS to ANAGND. BOOT 16 I Bootstrap. Connect a 1-µF low-ESR capacitor from BOOT to BOOTLO. BOOTLO 18 O Bootstrap low. Connect BOOTLO to the junction of the high-side and low-side FETs for floating drive
configuration. Connect BOOTLO to PGND for ground reference drive configuration.
DROOP 2 I Droop voltage. Voltage input used to set the amount of output-voltage set-point droop as a function of load
current. The amount of droop compensation is set with a resistor divider between IOUT and ANAGND. DRV 14 O Drive regulator for the FET drivers. A 1-µF ceramic capacitor should be connected from DRV to DRVGND. DRVGND 12 Drive ground. Ground for FET drivers. Connect to FET PWRGND. HIGHDR 17 O High drive. Output drive to high-side power switching FETs HISENSE 19 I High current sense. For current sensing across high-side FETs, connect to the drain of the high-side FETs; for
optional resistor sensing scheme, connect to power supply side of current-sense resistor placed in series with
high-side FET drain. INHIBIT 22 I Disables the drive signals to the MOSFET drivers. Can also serve as UVLO for system logic supply (either 3.3 V
or 5 V). IOUT 1 O Current out. Output voltage on this pin is proportional to the load current as measured across the Rds(on) of the
high-side FET s. The voltage on this pin equals 2×R
ds(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
FET s. IOUTLO 21 O Current sense low output. This is the voltage on the LOSENSE pin when the high-side FETs are on. A ceramic
capacitor should be connected from IOUTLO to HISENSE to hold the sensed voltage while the high-side FET s
are off. Capacitance range should be between 0.033 µF and 0.1 µF. LODRV 10 I Low drive enable. Normally tied to 5 V. To activate the low-side FETs as a crowbar, pull LODRV low. LOHIB 11 I Low side inhibit. Connect to the junction of the high and low side FET s to control the anti-cross-conduction and
eliminate shoot-through current. Disabled when configured in crowbar mode. LOSENSE 20 I Low current sense. For current sensing across high-side FETs, connect to the source of the high-side FET s; for
optional resistor sensing scheme, connect to high-side FET drain side of current-sense resistor placed in series
with high-side FET drain. LOWDR 13 O Low drive. Output drive to synchronous rectifier FETs OCP 3 I Over current protection. Current limit trip point is set with a resistor divider between IOUT and ANAGND. PWRGD 28 O Power good. Power Good signal goes high when output voltage is within 7% of voltage set by VID pins.
Open-drain output. SLOWST 8 O Slow Start (soft start). A capacitor from SLOWST to ANAGND sets the slowstart time.
Slowstart current = I
VREFB
/5
V
CC
15 12-V supply. A 1-µF ceramic capacitor should be connected from VCC to DRVGND.
VHYST 4 I HYSTERESIS set pin. The hysteresis is set with a resistor divider from V
REFB
to ANAGND.
The hysteresis window = 2 × (V
REFB
– V
HYST
) VID0 27 I Voltage Identification input 0 VID1 26 I Voltage Identification input 1 VID2 25 I Voltage Identification input 2 VID3 24 I Voltage Identification input 3 VID4 23 I Voltage Identification input 4. Digital inputs that set the output voltage of the converter. The code pattern for
setting the output voltage is located in T able 1. Internally pulled up to 5 V with a resistor divider biased from V
CC
.
VREFB 5 O Buffered reference voltage from VID network VSENSE 6 I Voltage sense Input. To be connected to converter output voltage bus to sense and control output voltage. It is
recommended an RC low pass filter be connected at this pin to filter noise.
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
4
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
detailed description
V
REF
The reference/voltage identification (VID) section consists of a temperature-compensated bandgap reference and a 5-bit voltage selection network. The 5 VID terminals are inputs to the VID selection network and are TTL-compatible inputs internally pulled up to 5 V by a resistor divider connected to V
CC
. The VID codes conform
to the Intel
VRM 8.3 DC-DC Converter Specification
for voltage settings between 1.8 V and 3.5 V , and they are
decremented by 50 mV , down to 1.3 V, for the lower VID settings. V oltages higher than V
REF
can be implemented
using an external divider. Refer to T able 1 for the VID code settings. The output voltage of the VID network, V
REF
,
is within ±1% of the nominal setting over the VID range of 1.3 V to
2
.5 V , including a junction temperature range
of 5°C to +125°C, and a V
CC
supply voltage range of 1 1.4 V to 12.6 V . The output of the reference/VID network
is indirectly brought out through a buffer to the V
REFB
pin. The voltage on this pin will be within 2% of V
REF
. It
is not recommended to drive loads with V
REFB
, other than setting the hysteresis of the hysteretic comparator,
because the current drawn from V
REFB
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 V
REF
. The 2 external resistors form a resistor divider from V
REFB
to ANAGND, with the output voltage connecting to the V
HYST
pin. The hysteresis of the comparator will be equal
to twice the voltage
difference
between the V
REFB
and V
HYST
pins. The propagation delay from the comparator
inputs to the driver outputs is 250 ns (maximum). The maximum hysteresis setting is 60 mV.
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 and 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 and 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 DR V regulator. The internal bootstrap diode, connected between the DR V 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 V
CC
.
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 s is below 2 V ; the low-side driver is not allowed to turn on until the voltage at the junction of the high-side and low-side FETs (Vphase) is below 2 V.
current sensing
Current sensing is achieved by sampling and holding the voltage across the high-side power FETs while the high-side FET s are on. The sampling network consists of an internal 60- switch and an external ceramic hold capacitor. Recommended value of the hold capacitor is between 0.033 µF and 0.1 µF. 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 . The sampling will occur only when the high-side FETs are 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 FETs, and the voltage across the sense resistor can be sampled by the current sensing circuit.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
5
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
detailed description (continued)
droop compensation
The droop compensation network reduces the load transient overshoot/undershoot on V
O
, relative to V
REF
. V
O
is programmed to a voltage greater than V
REF
by an external resistor divider from VO to VSENSE to reduce the
undershoot on V
O
during a low-to-high load transient. The overshoot during a high-to-low load transient is
reduced by subtracting the voltage on DROOP from V
REF
. The voltage on IOUT is divided with an external
resistor divider, and connected to DROOP.
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. 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 start threshold is 2.1 V and the hysteresis is 100 mV for the INHIBIT comparator.
V
CC
undervoltage lockout (UVLO)
The undervoltage lockout circuit disables the controller while the V
CC
supply is below the 10-V start threshold during power up. When the controller is disabled, the output drivers will be low and the slowstart capacitor is discharged. When V
CC
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 V
O
powers up. A capacitor is connected between SLOWST and ANAGND and is charged by an internal current source. The current source is proportional to the reference voltage, so that the charging rate of C
slowst
is proportional to the reference voltage. By making the charging
current proportional to V
REF
, the power-up time for VO will be independent of V
REF
. Thus, C
SLOWST
can remain
the same value for all VID settings. The slowstart charging current is determined by the following equation:
I
slowstart
= I(V
REFB
) / 5 (amps)
Where I(V
REFB
) is the current flowing out of V
REFB
.
It is recommended that no additional loads be connected to V
REFB
, other than the resistor divider for setting the
hysteresis voltage. The maximum current that can be sourced by the V
REFB
circuit is 500 µA. The equation for
setting the slowstart time is:
t
SLOWST
= 5 × C
SLOWST
× R
VREFB
(seconds)
Where R
VREFB
is the total external resistance from V
REFB
to ANAGND.
power good
The power-good circuit monitors for an undervoltage condition on V
O
. If VO is 7% below V
REF
, then the PWRGD
pin is pulled low. PWRGD is an open-drain output.
overvoltage protection
The overvoltage protection (OVP) circuit monitors V
O
for an overvoltage condition. If VO is 15% above V
REF
,
then a fault latch is set and both output drivers are turned off. The latch will remain set until V
CC
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 microprocessor against overvoltages due to a shorted fault across the high-side power FET.
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
6
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
detailed description (continued)
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 the OCP pin. If the voltage on OCP exceeds 100 mV , then a fault latch is set and the output drivers are turned off. The latch will remain set until V
CC
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.
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 microprocessor against overvoltages that can occur if the high-side power FETs become shorted. External components to sense an overvoltage condition are required to use this feature. When an overvoltage fault occurs, the low-side FET s are used as a crowbar . LODR V is pulled low and the low-side FET will be turned on, overriding all control signals inside the TPS5210 controller. The crowbar action will short the input supply to ground through the faulted high-side FETs and the low-side FETs. A fuse in series with V
in
should be added to disconnect the short-circuit.
Table 1. Voltage Identification Codes
VID TERMINALS
(0 = GND, 1 = floating or pull-up to 5 V)
V
REF
VID4 VID3 VID2 VID1 VID0 (Vdc)
0 1 1 1 1 1.30 0 1 1 1 0 1.35 0 1 1 0 1 1.40 0 1 1 0 0 1.45 0 1 0 1 1 1.50 0 1 0 1 0 1.55 0 1 0 0 1 1.60 0 1 0 0 0 1.65 0 0 1 1 1 1.70 0 0 1 1 0 1.75 0 0 1 0 1 1.80 0 0 1 0 0 1.85 0 0 0 1 1 1.90 0 0 0 1 0 1.95 0 0 0 0 1 2.00 0 0 0 0 0 2.05 1 1 1 1 1 No CPU 1 1 1 1 0 2.10 1 1 1 0 1 2.20 1 1 1 0 0 2.30 1 1 0 1 1 2.40 1 1 0 1 0 2.50 1 1 0 0 1 2.60
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
7
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Table 1. Voltage Identification Codes (Continued)
VID TERMINALS
(0 = GND, 1 = floating or pull-up to 5 V)
V
REF
VID4 VID3 VID2 VID1 VID0 (Vdc)
1 1 0 0 0 2.70 1 0 1 1 1 2.80 1 0 1 1 0 2.90 1 0 1 0 1 3.00 1 0 1 0 0 3.10 1 0 0 1 1 3.20 1 0 0 1 0 3.30 1 0 0 0 1 3.40 1 0 0 0 0 3.50
absolute maximum ratings over operating virtual junction temperature (unless otherwise noted)
Supply voltage range, V
CC
(see Note1) –0.3 V to 14 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range: BOOT to DRVGND (High-side Driver ON) –0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . .
BOOT to HIGHDRV –0.3 V to 15 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BOOT to BOOTLO –0.3 V to 15 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INHIBIT, VIDx, LODRV –0.3 V to 7.3 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PWRGD, OCP, DROOP –0.3 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LOHIB, LOSENSE, IOUTLO, HISENSE –0.3 V to 14 V. . . . . . . . . . . . . . . . . . . . . . . . . .
VSENSE –0.3 V to 5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage difference between ANAGND and DRVGND ±0.5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output current, V
REFB
0.5 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short circuit duration, DRV Continuous. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous total power dissipation See Dissipation Rating Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating virtual junction temperature range, T
J
0°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
–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
DW 1200 mW 12 mW/°C 660 mW 480 mW
PWP 1150 mW 11.5 mW/°C 630 mW 460 mW
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
8
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
recommended operating conditions
MIN MAX UNIT
Supply voltage, V
CC
11.4 13 V
Input voltage, BOOT to DRVGND 0 28 V
Input voltage, BOOT to BOOTLO 0 13 V Input voltage, INHIBIT, VIDx, LODRV, PWRGD, OCP, DROOP 0 6 V Input voltage, LOHIB, LOSENSE, IOUTLO, HISENSE 0 13 V Input voltage, VSENSE 0 4.5 V Voltage dif ference between ANAGND and DRVGND 0 ±0.2 V Output current, V
REFB
0 0.4 mA
Not recommended to load V
REFB
other than to set hystersis since I
VREFB
sets slowstart time.
electrical characteristics over recommended operating virtual junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted)
reference/voltage identification
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VCC = 11.4 to 12.6 V, 1.3 V V
REF
2.5 V –0.01 0.01 V/V
VCC = 11.4 to 12.6 V, V
REF
= 2.6 V –0.0104 0.0104 V/V
VCC = 11.4 to 12.6 V, V
REF
= 2.7 V –0.0108 0.0108 V/V
VCC = 11.4 to 12.6 V, V
REF
= 2.8 V –0.0112 0.0112 V/V
VCC = 11.4 to 12.6 V, V
REF
= 2.9 V –0.0116 0.0116 V/V
Reference voltage accuracy, (Includes
offset of droop compensation net-
VCC = 11.4 to 12.6 V, V
REF
= 3 V –0.0120 0.0120 V/V
work)
VCC = 11.4 to 12.6 V, V
REF
= 3.1 V –0.0124 0.0124 V/V
VCC = 11.4 to 12.6 V, V
REF
= 3.2 V –0.0128 0.0128 V/V
V
VCC = 11.4 to 12.6 V, V
REF
= 3.3 V –0.0132 0.0132 V/V
V
REF
VCC = 11.4 to 12.6 V, V
REF
= 3.4 V –0.0136 0.0136 V/V
VCC = 11.4 to 12.6 V, V
REF
= 3.5 V –0.0140 0.0140 V/V
V
REF
= 1.3 V, Hysteresis window = 30 mV –0.011 0.011
V
REF
=1.3 V , Hysteresis,
TJ = 60°C window = 30 mV (see Note 3)
–0.008 0.008
Cumulative reference accurac
y
(see Note 2)
V
REF
= 1.9 Vv, Hysteresis,
TJ = 60°C window = 30 mV (see Note 3)
–0.0090 0.0090
V/V
V
REF
= 3.5 V, Hysteresis,
TJ = 60°C window = 30 mV (see Note 3)
–0.0115 0.0115
VIDx High-level input voltage 2.25 V VIDx Low-level input voltage 1 V
Output voltage I
VREFB
= 50 µA V
REF
–2% V
REFVREF
+2% V
V
REFB
Output regulation 10 µA IO 500 µA 2 mV Input resistance VIDx = 0 V 36 73 95 k
VID
x
Input pull-up voltage divider 4.8 4.9 5 V
NOTES: 2. Cumulative reference accuracy is the combined accuracy of the reference voltage and the input offset voltage of the hysteretic
comparator. Cumulative accuracy equals the average of the high-level and low-level thresholds of the hysteretic comparator.
3. This parameter is ensured by design and is not production tested.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
9
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
electrical characteristics over recommended operating virtual junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted) (continued)
power good
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Undervoltage trip threshold 90 93 95 %V
REF
V
OL
Low-level output voltage IO = 5 mA 0.5 0.75 V
I
OH
High-level input current V
PWRGD
= 6 V 1 µA
V
hys
Hysteresis voltage 1.3 2.9 4.5 %V
REF
slowstart
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Charge current
V
SLOWST
= 0.5 V,
I
VREFB
= 65 µA
V
VREFB
= 1.3 V,
10.4 13 15.6 µA
Discharge current V
SLOWST
= 1 V 3 mA Comparator input offset voltage 10 mV Comparator input bias current See Note 3 10 100 nA Comparator hysteresis –7.5 7.5 mV
NOTE 3: This parameter is ensured by design and is not production tested.
hysteretic comparator
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Input offset voltage V
DROOP
= 0 V (see Note 3) –2.5 2.5 mV Input bias current See Note 3 500 nA Hysteresis accuracy V
REFB
– V
HYST
= 15 mV
(Hysteresis window = 30 mV)
–3.5 3.5 mV
Maximum hysteresis setting V
REFB
– V
HYST
= 30 mV 60 mV
NOTE 3: This parameter is ensured by design and is not production tested.
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
10
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
electrical characteristics over recommended operating virtual junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted) (continued)
high-side VDS sensing
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Gain 2 V/V Initial accuracy
V
HISENSE
= 12 V, V
LOSENSE
= 11.9 V,
Differential input to Vds sensing amp = 100 mV
194 206 mV
IOUTLO Sink current 5 V V
IOUTLO
13 V 250 nA
IOUT Source current
V
IOUT
= 0.5 V, V
HISENSE
= 12 V,
V
IOUTLO
= 11.5 V
500 µA
IOUT Sink current
V
IOUT
= 0.05 V , V
HISENSE
= 12 V ,
V
IOUTLO
= 12 V
50 µA
V
HISENSE
= 11 V, R
IOUT
= 10 k 0 2 V
Output voltage swing
V
HISENSE
= 4.5 V, R
IOUT
= 10 k 0 1.5 V
V
HISENSE
= 3 V, R
IOUT
= 10 k 0 0.75 V
High-level input voltage
2.85 V
LOSENSE
Low-level input voltage
V
HISENSE
=
4.5 V (see Note 3)
2.4 V
11.4 V V
HISENSE
12.6 V, LOSENSE connected to HISENSE, V
HISENSE
– V
IOUTLO
= 0.15 V
50 60 80
Sample/hold resistance
4.5 V V
HISENSE
5.5 V, LOSENSE connected to HISENSE, V
HISENSE
– V
IOUTLO
= 0.15 V
62 85 123
3 V V
HISENSE
3.6 V, LOSENSE connected to HISENSE, V
HISENSE
– V
IOUTLO
= 0.15 V
67 95 144
CMRR
V
HISENSE
= 12.6 V to 3 V,
V
HISENSE
– V
OUTLO
= 100 mV
69 75 dB
NOTE 3. This parameter is ensured by design and is not production tested.
inhibit
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Start threshold 1.9 2.1 2.35 V Hysteresis 0.08 0.1 0.12 V Stop threshold 1.85 V
overvoltage protection
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Overvoltage trip threshold 112 115 120 %V
REF
Hysteresis See Note 3 10 mV
NOTE 3: This parameter is ensured by design and is not production tested.
overcurrent protection
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
OCP trip threshold 90 100 110 mV Input bias current 100 nA
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
11
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
electrical characteristics over recommended operating virtual junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted) (continued)
deadtime
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
High-level input voltage 2.4
LOHIB
Low-level input voltage 1.4
V
High-level input voltage See Note 3 3
LOWDR
Low-level input voltage See Note 3 1.7
V
NOTE 3: This parameter is ensured by design and is not production tested.
LODRV
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
High-level input voltage 1.85
LODRV
Low-level input voltage 0.95
V
droop compensation
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Initial accuracy V
DROOP
= 50 mV 46 54 mV
drive regulator
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Output voltage 11.4 V VCC 12.6 V, I
DRV
= 50 mA 7 9 V
Output regulation 1 mA I
DRV
50 mA 100 mV
Short-circuit current 100 mA
bias regulator
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Output voltage 11.4 V VCC 12.6 V, See Note 4 6 V
NOTE 4: The bias regulator is designed to provide a quiet bias supply for the TPS5210 controller. External loads should not be driven by the bias
regulator.
input undervoltage lockout
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Start threshold 9.25 10 10.75 V Hysteresis 1.9 2 2.2 V Stop threshold 7.5 V
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
12
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
electrical characteristics over recommended operating virtual junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted) (continued)
output drivers
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
High-side sink
Duty cycle < 2%, TJ = 125°C,
tpw < 100 µs, V
BOOT
– V
BOOTLO
= 6.5 V,
2
Peak output
High-side source
V
HIGHDR
= 1.5 V (source) or 6 V (sink),
See Note 3
2
curren
t
(see Note 5)
Low-side sink
Duty Cycle < 2%, TJ = 125°C,
tpw < 100 µs, V
DRV
= 6.5 V,
2
A
Low-side source
V
LOWDR
= 1.5 V (source) or 5 V (sink),
See Note 3
2
High-side sink
T
= 125°C, V
– V
= 6.5 V,
3
Output
High-side source
J
,
BOOT BOOTLO
,
V
HIGHDR
= 6 V (source) or 0.5 V (sink)
45
resistance (
see Note 5
)
Low-side sink
TJ = 125°C, V
DRV
= 6.5 V,
5.7
(see Note 5)
Low-side source
J DRV
V
LOWDR
= 6 V (source) or 0.5 V (sink)
45
NOTES: 3. This parameter is ensured by design and is not production tested.
5. The pull-up/pull-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 R
ds(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 MIN TYP MAX UNIT
V
CC
Supply voltage range
11.4 12 13 V
V
INHIBIT
= 5 V,
VCC > 10.75 V at startup,
VID code 11111, V
BOOTLO
= 0 V
3 10
V
CC
Quiescent current
V
INHIBIT
= 5 V, VCC > 10.75 V at startup, C
HIGHDR
= 50 pF,
f
SWX
= 200 kHz,
VID code 11111, V
BOOTLO
= 0 V,
C
LOWDR
= 50 pF,
See Note 3
5
mA
High-side
V
INHIBIT
= 0 V or VID code = 11111 or VCC < 9.25 V at startup, V
BOOT
= 13 V, V
BOOTLO
= 0 V
80 µA
driver
quiescent current
V
INHIBIT
= 5 V, V
BOOT
= 13 V,
C
HIGHDR
= 50 pF,
VID code 11111, VCC > 10.75 V at startup, V
BOOTLO
= 0 V,
f
SWX
= 200 kHz (see Note 3)
2 mA
NOTE 3: This parameter is ensured by design and is not production tested.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
13
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
switching characteristics over recommended operating virtual-junction temperature range, V
CC
= 12 V, I
DRV
= 0 A (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VSENSE to HIGHDR or LOWDR (excluding dead­time)
1.3 V V
VREF
3.5 V, 10 mV overdrive
(see Note 3)
150 250 ns
p
OCP comparator 1
Pro agation delay
OVP comparator
See Note 3
1
µs PWRGD comparator 1 SLOWST comparator Overdrive = 10 mV (see Note 3) 560 900 ns
HIGHDR output
CL = 9 nF, V
BOOT
= 6.5 V,
V
BOOTLO
= 0 V, TJ = 125°C
60
Rise time
LOWDR output
CL = 9 nF, V
DRV
= 6.5 V,
TJ = 125°C
60
ns
HIGHDR output
CL = 9 nF, V
BOOT
= 6.5 V,
V
BOOTLO
= 0 V, TJ = 125°C
60
Fall time
LOWDR output
CL = 9 nF, V
DRV
= 6.5 V,
TJ = 125°C
60
ns
Deglitch time (Includes
p
p
p
OCP
2 5 comparator propagation delay)
OVP
See Note 3
2 5
µ
s
V
HISENSE
= 12 V,
V
IOUTLO
pulsed from 12 V to 11.9 V,
100 ns rise/fall times (see Note 3)
2
Response time High-side VDS sensing
V
HISENSE
= 4.5 V,
V
IOUTLO
pulsed from 4.5 V to 4.4 V ,
100 ns rise/fall times (see Note 3)
3
µs
V
HISENSE
= 3 V,
V
IOUTLO
pulsed from 3 V to 2.9 V ,
100 ns rise/fall times (see Note 3)
3
Short-circuit protection rising-edge delay
SCP LOSENSE = 0 V (see Note 3) 300 500 ns
Turn-on/turn-off delay
VDS sensing sample/hold switch
3 V V
HISENSE
11 V,
V
LOSENSE
= V
HISENSE
(see Note 3)
30 100 ns
Crossover delay time
LOWDR to HIGHDRV, and LOHIB to LOWDR
See Note 3 30 100 ns
Prefilter pole frequency Hysteretic comparator See Note 3 5 MHz Propagation delay LODRV See Note 3 400 ns
NOTE 3: This parameter is ensured by design and is not production tested.
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
14
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 1
SLOWSTART TIME
vs
SLOWSTART CAPACITANCE
0.0001 0.0010
Slowstart Capacitance – µF
100
0
10
1
0.1
Slowstart Time – ms
V
(VREFB)
= 2 V
I
(VREFB)
= 100 µA
TJ = 25°C
0.0100 0.1000 1
Figure 2
SLOWSTART TIME
vs
SUPPLY CURRENT (VREFB)
110
I
CC
– Supply Current (VREFB) – µA
1000
1
10
Slowstart Time – ms
V
(VREFB)
= 2 V CS = 0.1 µF TJ = 25°C
100 1000
100
Figure 3
DRIVER
OUTPUT RISE TIME
vs
LOAD CAPACITANCE
0.1 1 CL – Load Capacitance – nF
100
1
10
– Rise Time – ns
TJ = 25°C
10 100
t
r
High Side
Low Side
Figure 4
CL – Load Capacitance – nF
0.1 1
1000
1
10
10 100
100
– Fall Time – nst
f
DRIVER
OUTPUT FALL TIME
vs
LOAD CAPACITANCE
TJ = 25°C
High Side
Low Side
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
15
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 5
TJ – Junction Temperature – °C
OVP THRESHOLD
vs
JUNCTION TEMPERATURE
117
114
112
25 75
116
115
113
50 100 125
118
0
OVP Threshold – %
Figure 6
TJ – Junction Temperature – °C
OCP THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
99
95
25 75
103
101
97
50 100 125
105
0
OCP Threshold V oltage – mV
Figure 7
TJ – Junction Temperature – °C
INHIBIT START THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
2
1.9 25 75
2.05
1.95
50 100 125
2.1
0
Inhibit Start Threshold Voltage – V
Figure 8
TJ – Junction Temperature – °C
INHIBIT HYSTERESIS VOLTAGE
vs
JUNCTION TEMPERATURE
100
50
25 75
125
75
50 100 125
150
0
Inhibit Hysteresis Voltage – mV
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
16
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 9
TJ – Junction Temperature – °C
UVLO START THRESHOLD VOLTAGE
vs
JUNCTION TEMPERATURE
10
9
25 75
9.5
50 100 125
10.5
0
UVLO Start Threshold Voltage – V
VI = 12 V
Figure 10
TJ – Junction Temperature – °C
UVLO HYSTERESIS
vs
JUNCTION TEMPERATURE
1.9
1.5 25 75
2.3
2.1
1.7
50 100 125
2.5
0
UVLO Hysteresis – V
VI = 12 V
Figure 11
TJ – Junction Temperature – °C
QUIESCENT CURRENT
vs
JUNCTION TEMPERATURE
4
0
25 75
2
50 100 125
6
0
Quiescent Current – mA
VI = 12 V
Figure 12
TJ – Junction Temperature – °C
POWERGOOD THRESHOLD
vs
JUNCTION TEMPERATURE
92
90
25 75
94
93
91
50 100 125
95
0
Powergood Threshold – %
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
17
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 13
TJ – Junction Temperature – °C
SLOW START CHARGE CURRENT
vs
JUNCTION TEMPERATURE
12
10
25 75
14
13
11
50 100 125
15
0
Slow Start Charge Current – Aµ
V
(VREFB)
= 1.3 V
R
(VREFB)
= 20 k
Figure 14
TJ – Junction Temperature – °C
DRIVER
REGULATOR VOLTAGE
vs
JUNCTION TEMPERATURE
8
7.5 25 75
8.25
7.75
50 100 125
8.5
0
Regulator Voltage – V
Figure 15
TJ – Junction Temperature – °C
DRIVER
HIGH-SIDE OUTPUT RESISTANCE
vs
JUNCTION TEMPERATURE
2
0
25 75
4
3
1
50 100 125
5
0
– High-Side Output Resistance – R
O
Figure 16
TJ – Junction Temperature – °C
DRIVER
LOW-SIDE OUTPUT RESISTANCE
vs
JUNCTION TEMPERATURE
4
0
25 75
2
50 100 125
6
0
– Low-Side Output Resistance – R
O
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
18
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
TJ – Junction Temperature – °C
SENSING SAMPLE/HOLD RESISTANCE
vs
JUNCTION TEMPERATURE
50
0
25 75
75
25
50 100 125
100
0
– Sensing Sample/Hold Resistance – R
O
V
(HISENSE)
= 12 V
Figure 17
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
19
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
The following figure is a typical application schematic. The circuit can be divided into the power-stage section and the control-circuit section. The power stage must be tailored to the input/output requirements of the application. The control circuit is basically the same for all applications with some minor tweaking of specific values. Table 2 shows the values of the power stage components for various output-current options.
10
LODRV
11
LOHIB
12
DRVGND
13
LOWDR
14
DRV
16
BOOT
17
HIGHDR
18
BOOTLO
19
HISENSE
15
VCC
23
VID4
24
VID3
25
VID2
26
VID1
27
VID0
22
INHIBIT
28
PWRGD
1
IOUT
9
BIAS
3
OCP
4
VHYST
6
VSENSE
5
VREFB
7
ANAGND
8
SLOWST
2
DROOP
20
LOSENSE
21
IOUTLO
TPS5210
U1
C6
0.033 uF
1 uF
C3
R4
2.55 k 1%
ENABLE
C8
2200 pF
1%
R1
3.40 k
1 uF
C1
R101
GND
Control Section
Power Stage
12V
Q101
L101
C103C102
+
C101
Q102
+
C105
C106
Vo
L102
R102
C104
RTN
R10
1.00 k
R9
4.32 k
1.00 k
R8
R7
3.92 k
20.0 k
R6
100
R5
10.0 kR3
C7
1000 pF
C5
0.1 uF
C4
1 uF
R2
150
1 uF
C2
12V
HIGHDRV
HISENSE
LOSENSE
BOOTLO
DRVGND
LOHIB
LODRV
VSENSE
RTN
Figure 18. Standard Application Schematic
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
20
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
Table 2. Power Stage Components
Ref
12-V–Input Power Stage Components
Des
Function
4–A Out 8–A Out 12–A Out 20–A Out 40–A Out
C101
Input Bulk Capacitor
Sanyo, 16SV100M, 100–uF, 16–V, 20%
Sanyo, 16SA470M, 2 x 470–uF , 16–V, 20%
Sanyo, 16SA470M, 2 x 470–uF , 16–V, 20%
Sanyo, 16SA470M, 3 x 470–uF , 16–V, 20%
Sanyo, 16SA470M, 4 x 470–uF , 16–V, 20%
C102
Input Mid–Freq Capacitor
muRata, GRM42–6Y5V105Z025A
1.0–uF, 25–V, +80%–20%, Y5V
muRata, GRM42–6Y5V225Z016A
2.2–uF, 16–V, +80%–20%, Y5V
muRata, GRM42–6Y5V225Z016A
2.2–uF, 16–V, +80%–20%, Y5V
muRata, GRM42–6Y5V105Z025A 3 x 1.0–uF , 25–V, +80%–20%, Y5V
muRata, GRM42–6Y5V105Z025A 4 x 1.0–uF , 25–V, +80%–20%, Y5V
C103
Input Hi–Freq Bypass Capacitor
muRata, GRM39X7R104K016A
0.1–uF, 16–V, X7R
muRata, GRM39X7R104K016A,
0.1–uF, 16–V, X7R
muRata, GRM39X7R104K016A, 2 x 0.1–uF , 16–V, X7R
muRata, GRM39X7R104K016A, 3 x 0.1–uF , 16–V, X7R
muRata, GRM39X7R104K016A, 4 x 0.1–uF , 16–V, X7R
C104
Snubber Capacitor
muRata, GRM39X7R102K050A, 1000–pF, 50–V, X7R
muRata, GRM39X7R102K050A, 1000–pF, 50–V, X7R
muRata, GRM39X7R102K050A, 2 x 1000–pF , 50–V, X7R
muRata, GRM39X7R102K050A, 3 x 1000–pF , 50–V, X7R
muRata, GRM39X7R102K050A, 4 x 1000–pF , 50–V, X7R
C105
Output Bulk Capacitor
Sanyo, 6TPB150M, 3 x 150–uF , 6.3–V, 20%
Sanyo, 4SP820M, 820–uF, 4–V, 20%
Sanyo, 4SP820M, 2 x 820–uF , 4–V, 20%
Sanyo, 4SP820M, 3 x 820–uF , 4–V, 20%
Sanyo, 4SP820M, 4 x 820–uF , 4–V, 20%
C106
Output Hi–Freq Bypass Capacitor
muRata, GRM39X7R104K016A,
0.1–uF, 16–V, X7R
muRata, GRM39X7R104K016A,
0.1–uF, 16–V, X7R
muRata, GRM39X7R104K016A, 2 x 0.1–uF , 16–V, X7R
muRata, GRM39X7R104K016A, 3 x 0.1–uF , 16–V, X7R
muRata, GRM39X7R104K016A, 4 x 0.1–uF , 16–V, X7R
L101
Input Filter Inductor
CoilCraft, DO1608C–332,
3.3–uH, 2.0–A
Coiltronics, UP2B–2R2,
2.2–uH, 7.2–A
Coiltronics, UP2B–2R2,
2.2–uH, 7.2–A
Coiltronics, UP3B–1R0, 1–uH, 12.5–A
Coiltronics, UP3B–1R0, 1–uH, 12.5–A
L102
Output Filter Inductor
CoilCraft, DO3316P–332,
3.3–uH, 6.1–A
Coiltronics, UP3B–2R2,
2.2–uH, 9.2–A
Coiltronics, UP4B–1R5,
1.5–uH, 13.4–A
MicroMetals, T68–8/90 Core w/7T #16, 1.0–uH, 25–A
Pulse Engineering, P1605,
1.0–uH, 50–A
R101
Lo–Side Gate Resistor
3.3–Ohm, 1/16–W, 5%
3.3–Ohm, 1/16–W, 5%
2 x 3.3–Ohm, 1/16–W, 5%
3 x 3.3–Ohm, 1/16–W, 5%
4 x 3.3–Ohm, 1/16–W, 5%
R102
Snubber Resistor
2.7–Ohm, 1/10–W, 5%
2.7–Ohm, 1/10–W, 5%
2 x 2.7–Ohm, 1/10–W, 5%
3 x 2.7–Ohm, 1/10–W, 5%
4 x 2.7–Ohm, 1/10–W, 5%
Q101
Power Switch
Siliconix, Si4410, NMOS, 13–mOhm
Siliconix, Si4410, NMOS, 13–mOhm
Siliconix, 2 x Si4410, NMOS, 13–mOhm
Siliconix, 2 x Si4410, NMOS, 13–mOhm
IR, 2 x IRF7811, NMOS, 11–mOhm
Q102
Synchron­ous Switch
Siliconix, Si4410, NMOS, 13–mOhm
Siliconix, Si4410, NMOS, 13–mOhm
Siliconix, 2 x Si4410, NMOS, 13–mOhm
Siliconix, 3 x Si4410, NMOS, 13–mOhm
IR, 4 x IRF7811, NMOS, 11–mOhm
Nominal Frequency†220 KHz 330 KHz 240 KHz 140 KHz 168 KHz Hysteresis Window 20 mV 20 mV 20 mV 20 mV 10 mV
Nominal frequency measured with Vo set to 2 V.
The values listed above are recommendations based on actual test circuits. Many variations of the above are possible based upon the desires and/or requirements of the user. Performance of the circuit is equally, if not more, dependent upon the layout than on the specific components, as long as the device parameters are not exceeded. Fast-response, low-noise circuits require critical attention to the layout details. Even though the operating frequencies of typical power supplies are relatively low compared to today’s microprocessor circuits, the power levels and edge rates can cause severe problems both in the supply and the load. The power stage, having the highest current levels and greatest dv/dt rates, should be given the greatest attention.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
21
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
frequency calculation
A detailed derivation of frequency calculation is shown in the application report, “
Designing Fast Response
Synchronous Buck Regulators Using the TPS5210
”, TI Literature number SL VA044. When less accurate results
are acceptable, the simplified equation shown below can be used:
f
s
ǒ
VO ƪVI*
V
O
ƫ
ESR
Ǔ
ǒ
VI L
Hysteresis Window
Ǔ
Control Section
Below are the equations needed to select the various components within the control section. Details and the derivations of the equations used in this section are available in the application report “
Designing Fast Response
Synchronous Buck Regulators Using the TPS5210
”, TI Literature number SLVA044.
output voltage selection
Of course the most important function of the power supply is to regulate the output voltage to a specific value. V alues between 1.3 V and 3.5 V can be easily set by shorting the correct VID inputs to ground. Values above the maximum reference voltage (3.5 V) can be set by setting the reference voltage to any convenient voltage within its range and selecting values for R2 and R3 to give the correct output. Select R3:
R3 << than V
REF/IBIAS(VSENSE)
; a recommended value is 10 k
Then, calculate R2 using:
V
O
+
V
REF
ǒ
1
)
R2 R3
Ǔ
R2
+
R3
ǒ
VO*
V
REF
Ǔ
V
REF
or
R2 and R3 can also be used to make small adjusts to the output voltage within the reference-voltage range and/or to adjust for load-current active droop compensation. If there is no need to adjust the output voltage, R3 can be eliminated. R2, R3 (if used), and C7 are used as a noise filter; calculate using:
C7
+
150 ns
ǒ
R2øR3
Ǔ
slowstart timing
Slowstart reduces the startup stresses on the power-stage components and reduces the input current surge. Slowstart timing is a function of the reference-voltage current (determined by R6) and is independent of the reference voltage. The first step in setting slowstart timing will be to determine R6:
R6 should be between 7 k and 300 k, a recommended value is 20 kΩ.
Set the slowstart timing using the formula:
C5
+
t
SS
ǒ
5 R
VREFB
Ǔ
t
SS
(
5 R6
)
Where C5 = Slowstart capacitance in µF
t
SS
= Slowstart timing in µs
R
VREFB
= Resistance from VREFB to GND in ohms ( R6)
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
22
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
hysteresis voltage
A hysteretic controller regulates by self-oscillation, thus requiring a small ripple voltage on the output which the input comparator uses for sensing. Once selected, the TPS5210 hysteresis is proportional to the reference voltage; programming Vref to a new value automatically adjusts the hysteresis to be the same percentage of Vref. The actual output ripple voltage is the combination of the hysteresis voltage, overshoot caused by internal delays, and the output capacitor characteristics. Figure 20 shows the hysteresis window voltage (V
HI
to VLO)
and the output voltage ripple (V
MAX
to V
MIN
). Since the output current from VREFB should be less than 500 µA, the total divider resistance (R5 + R6) should be greater than 7 K. The hysteresis voltage should be no greater than 60 mV so R6 will dominate the divider.
R5
R6
VHSYT
VREFB
Hysteresis Window = 2 × V
R5
Figure 19. Hysteresis Divider Circuit
V
O
V
MAX
V
MIN
V
REF
V
HI
V
LO
t
Figure 20. Output Ripple
The upper divider resistor, R5, is calculated using:
()
()
()
6
1002
6
2
5
0
0
R
V
R
WindowHysteresisVREFB
WindowHysteresis
R
HYST
×
×
×
×
=
Where Hysteresis Window = the desired peak-to-peak hysteresis voltage.
VREFB = selected reference voltage. V
HYST
(%) = [(Hysteresis Window)/VREFB] * 100 < V
O(Ripple)(P–P)
(%)
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
23
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
current limit
Current limit can be implemented using the on-resistance of the upper FETs as the sensing elements. Select R8:
()
×
<<
nA
V
I
V
R
OCPBias
OCP
10 k
100100
1.0
8
)(
(A recommended value is 1 k)
The IOUT signal is used to drive the current limit and droop-circuit dividers. The voltage at IOUT at the output current trip point will be:
()
I
NumFETs
TF
R
V
TripO
ONDS
TripIOUT
)(
)(
)(
2
×
××
=
Where NumFETS = Number of upper FETS in Parallel.
TF = R
DS(ON)
temperature correction factor.
I
O(Trip)
= Desired output current trip level (A).
Calculate R7 using:
R7
+
ǒ
V
IOUT(Trip)
0.1 V
*
1Ǔ
R8
Note that since R
DS(ON)
of MOSFET s can vary from lot to lot and with temperature, tight current-limit control (less
than 1.5 x I
O
) using this method is not practical. If tight control is required, an external current-sense resistor in series with the drain of the upper FET can be used with HISENSE and LOSENSE connected across the resistor.
droop compensation
Droop compensation is used to reduce the output voltage range during load transients by increasing the output voltage setpoint toward the upper tolerance limit during light loads and decreasing the voltage setpoint toward the lower tolerance limit during heavy loads. This allows the output voltage to swing a greater amount and still remain within the tolerance window. The maximum droop voltage is set with R9 and R10. Select R10:
()
×
<<
nA
V
I
V
R
MaxDROOPBias
MinDROOP
1 k
100100
01.0
10
),(
)(
(Again, a value of 1 k is recommended)
The voltage at IOUT during normal operation (0 to 100% load) will vary from 0 V up to:
()
I
NumFETs
TF
R
V
MaxO
ONDS
MaxIOUT
)(
)(
)(
2
×
××
=
Where I
O(Max)
= Maximum output load current (A).
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
24
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
droop compensation (continued)
Then, calculate R9:
R9
+
ǒ
V
IOUT(Max)
V
DROOP
*
1Ǔ
R10
Where V
DROOP
= Desired droop voltage
At full load, the output voltage will be:
V
O
+
V
REF
ǒ1
)
R2 R3
Ǔ
*
V
DROOP
using the TPS5210 when both 12 V and 5 V are available
When both 12 V and 5 V are available, several components can be removed from the basic schematic shown above. R1, R4, and C9 are no longer required if 5 V is brought in directly to INHIBIT and LODRV. However, if undervoltage lockout for the 5-V input is desired, R1 and R4 can be used to set the startup setpoint. The INHIBIT pin trip level is 2.1 V. Select R4:
()
×
<<
k
nA
V
I
V
R
MaxINH
INH
210
100100
1.2
4
)(
Then, set the 5-V UVLO trip level with R1:
()
4
2
2
5
1
R
V
V
V
R
Trip
×
=
R1
R4
INHIBIT
LODRV
Figure 21. 5-V Input with UVLO
using the TPS5210 when only 5 V is available
The TPS5210 controller requires 12 V for internal control of the device. If an external source for 12 V is not available, a small on-board source must be included in the design. Total 12-V current is very small, typically about 20 mA, so even a small charge pump can be used to generate the supply voltage. The power stage is not voltage dependent, but component values must be selected for 5-V inputs and the frequency of operation is dependent upon the power stage input voltage.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
25
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
R4
11.0 k
R1
10.0 k
ENABLE
1%
12-V Boost Circuit
10
LODRV
11
LOHIB
12
DRVGND
13
LOWDR
14
DRV
16
BOOT
17
HIGHDR
18
BOOTLO
19
HISENSE
15
VCC
23
VID4
24
VID3
25
VID2
26
VID1
27
VID0
22
INHIBIT
28
PWRGD
1
IOUT
9
BIAS
3
OCP
4
VHYST
6
VSENSE
5
VREFB
7
ANAGND
8
SLOWST
2
DROOP
20
LOSENSE
21
IOUTLO
TPS5210
U1
C6
0.033 uF
0.1 uF
C1
1 uF
C3
1%
C8
2200 pF
12 V
GND
5V
Control Section
Power Stage
R101
Q101
L101
C103C102
+
C101
Q102
Vo
RTN
+
C105
C106
L102
R102
C104
R10
1.00 k
R9
4.32 k
1.00 k
R8
R7
3.92 k
20.0 k
R6
100
R5
10.0 kR3
C7
1000 pF
C5
0.1 uF
C4
1 uF
R2
150
1 uF
C2
5V
HIGHDRV
HISENSE
LOSENSE
BOOTLO
DRVGND
LOHIB
LODRV
VSENSE
RTN
Figure 22. Typical 5-V-Only Application Circuit
application examples
Various application and layout examples using the TPS5210 are available from Texas Instruments. This information can be downloaded from
http://www.ti.com/sc/docs/products/msp/pwrsply/default.htm
or received
from your TI representative.
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
26
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
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 TPS5210 design begins.
1. All sensitive analog components should be referenced to ANAGND. These include components connected to SLOWST, DROOP, 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 V
O
, 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 TPS5210 and be connected to DRVGND.
5. The bypass capacitor for V
CC
should be placed close to the TPS5210 and be connected to DRVGND.
6. When configuring the high-side driver as a floating driver , the connection from BOOTLO to the power FET s 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 TPS5210.
8. When configuring the high-side driver as a ground-referenced driver, BOOTLO should be connected to DRVGND.
9. The bulk storage capacitors across V
I
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 to the source of the low-side FET.
10. High-frequency bypass capacitors should be placed across the bulk storage capacitors on V
O
.
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. Ceramic decoupling capacitors should be placed close to where HISENSE connects to Vin, to reduce high-frequency noise coupling on HISENSE.
TPS5210
PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
27
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
MECHANICAL DATA
DW (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE
16 PIN SHOWN
4040000/C 07/96
Seating Plane
0.400 (10,15)
0.419 (10,65)
0.104 (2,65) MAX
1
0.012 (0,30)
0.004 (0,10)
A
8
16
0.020 (0,51)
0.014 (0,35)
0.293 (7,45)
0.299 (7,59)
9
0.010 (0,25)
0.050 (1,27)
0.016 (0,40)
(15,24)
(15,49)
PINS **
0.010 (0,25) NOM
A MAX
DIM
A MIN
Gage Plane
20
0.500
(12,70)
(12,95)
0.510
(10,16)
(10,41)
0.400
0.410
16
0.600
24
0.610
(17,78)
28
0.700
(18,03)
0.710
0.004 (0,10)
M
0.010 (0,25)
0.050 (1,27)
0°–8°
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice. C. Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15). D. Falls within JEDEC MS-013
TPS5210 PROGRAMMABLE SYNCHRONOUS BUCK REGULATOR CONTROLLER
SLVS171A – SEPTEMBER 1998 – REVISED MAY 1999
28
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
MECHANICAL DATA
PWP (R-PDSO-G**) PowerPAD PLASTIC SMALL-OUTLINE PACKAGE
4073225/E 03/97
0,50
0,75
0,25
0,15 NOM
Thermal Pad (See Note D)
Gage Plane
2824
7,70
7,90
20
6,40
6,60
9,60
9,80
6,60 6,20
11
0,19
4,50 4,30
10
0,15
20
A
1
0,30
1,20 MAX
1614
5,10
4,90
PINS **
4,90
5,10
DIM
A MIN
A MAX
0,05
Seating Plane
0,65
0,10
M
0,10
0°–8°
20-PIN SHOWN
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice. C. Body dimensions do not include mold flash or protrusions. D. The package thermal performance may be enhanced by bonding the thermal pad to an external thermal plane. This pad is electrically
and thermally connected to the backside of the die and possibly selected leads.
E. Falls within JEDEC MO-153
PowerPAD is a trademark of Texas Instruments Incorporated.
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