TPS650250-Q1
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SLVSAA7 – MARCH 2010
POWER MANAGEMENT IC FOR LI-ION POWERED SYSTEMS
Check for Samples: TPS650250-Q1
FEATURES
1
•
•
•
•
•
Qualified for Automotive Applications
1.6A, 97% Efficient Step-Down Converter for
System Voltage (VDCDC1)
– 3.3V or 2.8V or Adjustable
0.8A, up to 95% Efficient Step-Down Converter
for Memory Voltage (VDCDC2)
– 1.8V or 2.5V or Adjustable
0.8A, 90% Efficient Step-Down Converter for
Processor Core (VDCDC3)
Adjustable Output Voltage on VDCDC3
•
•
•
•
•
•
•
•
30mA LDO for Vdd_alive
2 × 200mA General Purpose LDOs (LDO1 and
LDO2)
Dynamic Voltage Management for Processor
Core
LDO1 and LDO2 Voltage Externally Adjustable
Separate Enable Pins for Inductive Converters
2.25MHz Switching Frequency
85mA Quiescent Current
Thermal Shutdown Protection
DESCRIPTION
The TPS650250 is an integrated Power Management IC for applications powered by one Li-Ion or Li-Polymer
cell, which require multiple power rails. The TPS650250 provides three highly efficient, step-down converters
targeted at providing the core voltage, peripheral, I/O and memory rails in a processor based system. All three
step-down converters enter a low power mode at light load for maximum efficiency across the widest possible
range of load currents. The converters can be forced into fixed frequency PWM mode by pulling the MODE pin
high.
The TPS650250 also integrates two general purpose 200mA LDO voltage regulators, which are enabled with an
external input pin. Each LDO operates with an input voltage range between 1.5V and 6.5V allowing them to be
supplied from one of the step-down converters or directly from the battery. The output voltage of the LDOs can
be set with an external resistor divider for maximum flexibility. Additionally there is a 30mA LDO typically used to
provide power in a processor based system to a voltage rail that is always on. TPS650250 comes in a small
5mm x 5mm 32-pin QFN package (RHB).
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2010, Texas Instruments Incorporated
TPS650250-Q1
SLVSAA7 – MARCH 2010
www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
Functional Block Diagram
TPS650250
1R
VCC
Vbat
1 mF
VINDCDC1
Vbat
DCDC1 (I/O)
10 mF
STEP-DOWN
CONVERTER
1600 mA
EN_DCDC1
ENABLE
VINDCDC2
Vbat
DCDC2
(memory)
10 mF
STEP-DOWN
CONVERTER
800 mA
EN_DCDC2
ENABLE
VINDCDC3
Vbat
3.3 V / 2.8 V
or adjustable
L1
10 mF
DCDC3 (core)
ENABLE
STEP-DOWN
CONVERTER
800 mA
EN_DCDC3
2.2 mH
VDCDC1
R1
22 mF
DEFDCDC1
PGND1
R2
2.5 V / 1.8 V
or adjustable
L2
2.2 mH
VDCDC2
R3
22 mF
DEFDCDC2
PGND2
R4
L3
2.2 mH
VDCDC3
R5
22 mF
DEFDCDC3
PGND3
R6
MODE
PWM/ PFM
VIN_LDO
VIN
VLDO1
VLDO1
200 mA LDO
EN_LDO
ENABLE
FB_LDO1 R7
2.2 mF
R8
VLDO2
200 mA LDO
VLDO2
FB_LDO2 R9
R10
EN_Vdd_alive
ENABLE
VCC
Vbat
2.2 mF
VLDO3
30 mA LDO
Vdd_alive
1V
2.2 mF
R11
I/O voltage
PWRFAIL_SNS
R12
-
PWRFAIL
R19
+
Vref = 1 V
AGND1
AGND2
ORDERING INFORMATION (1)
(1)
(2)
2
TJ
VOLTAGE AT
DCDC3
OUTPUT CURRENT ON
DCDC1 / DCDC2 / DCDC3
VOLTAGE AT
VDD_ALIVE
PACKAGE
ORDERABLE PART
NUMBER (2)
TOP-SIDE
MARKING
–40°C to 125°C
Adjustable
1.6A / 0.8A / 0.8A
1V
32-Pin QFN
(RHB)
TPS650250QRHBRQ1
TPS650250Q
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.
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SLVSAA7 – MARCH 2010
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted)
(1)
Input voltage range on all pins except A/PGND pins with respect to AGND
Voltage range on pins VLDO1, VLDO2, FB_LDO1, FB_LDO2
Current at VINDCDC1, L1, PGND1, VINDCDC2, L2, PGND2, VINDCDC3, L3, PGND3
Peak current at all other pins
Continuous total power dissipation
VALUE
UNIT
–0.3 to 7
V
–0.3 to 3.6
V
2000
mA
500
mA
See Dissipation Ratings
TJ
Operating junction temperature
–40 to 125
°C
Tst
Storage temperature
–65 to 150
°C
(1)
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.
DISSIPATION RATINGS
(1)
PACKAGE (1)
RqJA
TA ≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
RHB
35°C/W
2.85W
28mW/°C
TA = 70°C
TA = 85°C
TA = 105°C
POWER RATING POWER RATING POWER RATING
1.57W
1.14W
0.61W
The thermal resistance junction to ambient of the RHB package is measured on a high K board. The thermal resistance junction to
power pad is 1.5°C/W.
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RECOMMENDED OPERATING CONDITIONS
MIN
VCC
Input voltage range step-down converters, VINDCDC1, VINDCDC2, VINDCDC3
Output voltage range for step-down converter, VDCDC1
VO
(1)
Output voltage range for mem step-down converter, VDCDC2
(1)
NOM
MAX
UNIT
2.5
6.0
V
0.6
VINDCDC1
V
0.6
VINDCDC2
V
Output voltage range for core step-down converter, VDCDC3
0.6
VINDCDC3
V
VI
Input voltage range for LDOs, VINLDO1, VINLDO2
1.5
6.5
V
VO
Output voltage range for LDOs
IO
Output current at L, V1DCDC1
L1
Inductor at L1 (2)
1
1.5
CI
Input capacitor at VINDCDC1
(2)
10
CO
Output capacitor at VDCDC1 (2)
10
IO
Output current at L2, VDCDC2
L2
Inductor at L2 (2)
1.5
CI
Input capacitor at VINDCDC2
CO
Output capacitor at VDCDC2
(2)
IO
Output current at L3, VDCDC3
L3
Inductor at L3 (2)
1.5
CI
Input capacitor at VINDCDC3 (2)
10
CO
Output capacitor at VDCDC3
(2)
10
Input capacitor at VCC
Input capacitor at VINLDO (2)
CO
Output capacitor at VLDO1, VLDO2 (2)
IO
Output current at VLDO1, VLDO2
CO
Output capacitor at Vdd_alive (2)
IO
Output current at Vdd_alive
TJ
Operating junction temperature
RCC
(1)
(2)
(3)
4
10
10
mF
22
mF
2.2
mF
22
mF
2.2
mA
mH
mF
22
mF
1
mF
1
mF
mF
200
mA
30
mA
125
°C
10
Ω
2.2
mF
–40
Resistor from VINDCDC3,VINDCDC2, VINDCDC1 to VCC used for filtering
mA
mH
2.2
(3)
V
mA
mH
800
(2)
CI
2.2
800
(2)
CI
3.3
1600
1
When using an external resistor divider at DEFDCDC2, DEFDCDC1.
See applications section for more information, for VO > 2.85V choose 3.3mH inductor.
Up to 2.5mA can flow into VCC when all 3 converters are running in PWM, this resistor will cause the UVLO threshold to be shifted
accordingly.
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SLVSAA7 – MARCH 2010
ELECTRICAL CHARACTERISTICS
VINDCDC1 = VINDCDC2 = VINDCDC3 = VCC = VINLDO = 3.6V, TJ = –40°C to 125°C, typical values are at TA = 25°C
(unless otherwise noted)
CONTROL SIGNALS: EN_DCDC1, EN_DCDC2, EN_DCDC3, EN_LDO, MODE, EN_VDD_ALIVE
PARAMETER
VIH
High level input
voltage
VIL
Low level input
voltage
IH
Input bias current
TEST CONDITIONS
MIN
TYP
MAX
UNIT
1.45
VCC
V
0
0.4
V
0.01
0.1
mA
135
170
75
100
SUPPLY PINS: VCC, VINDCDC1, VINDCDC2, VINDCDC3
PFM All 3 DCDC converters enabled, zero load
and no switching, LDOs enabled
I(qPFM)
Operating quiescent
current
PFM All 3 DCDC converters enabled, zero load
and no switching, LDO1, LDO2 = OFF, Vdd_alive
= ON
PFM DCDC1 and DCDC2 converters enabled,
zero load and no switching, LDO1, LDO2 = OFF,
Vdd_alive = ON
VCC = 3.6V
PFM DCDC1 converter enabled, zero load and no
switching, LDO1, LDO2 = OFF, Vdd_alive = ON
All 3 DCDC converters enabled & running in PWM,
LDOs off
IVCC(PWM)
Current into VCC;
PWM
PWM DCDC1 converter enabled and running in
PWM, LDOs off
Iq
Quiescent current
All converters disabled, LDO1, LDO2 = OFF,
Vdd_alive = ON
55
80
40
60
2
PWM DCDC1 and DCDC2 converters enabled and
VCC = 3.6V
running in PWM, LDOs off
All converters disabled, LDO1, LDO2 = OFF,
Vdd_alive = OFF
mA
1.5
2.5
0.85
2
16
VCC = 3.6V
26
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mA
mA
5
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SLVSAA7 – MARCH 2010
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ELECTRICAL CHARACTERISTICS
VINDCDC1 = VINDCDC2 = VINDCDC3 = VCC = VINLDO = 3.6V, TJ = –40°C to 125°C, typical values are at TA = 25°C
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VDCDC1 STEP-DOWN CONVERTER
VI
Input voltage range,VINDCDC1
IO
Maximum output current
VO = 3.3V
ISD
Shutdown supply current in VINDCDC1
EN_DCDC1 = GND
0.1
1
mA
RDS(on)
P-channel MOSFET on-resistance
VINDCDC1 = VGS = 3.6V
125
261
mΩ
ILP
P-channel leakage current
VINDCDC1 = 6V
RDS(on)
N-channel MOSFET on-resistance
VINDCDC1 = VGS = 3.6V
ILN
N-channel leakage current
VDS = 6V
ILIMF
Forward current limit (P- and N-channel) 2.5V < VINMAIN < 6V
fS
Oscillator frequency
VDCDC1
Fixed output voltage
MODE=0 (PWM/PFM)
2.8V
Fixed output voltage
MODE=1 (PWM)
2.8V
2.5
3.3V
3.3V
6
1600
130
2
mA
260
mΩ
mA
7
10
1.7
1.97
2.22
A
1.95
2.25
2.55
MHz
VINDCDC1 = 3.3V to 6V;
0 mA ≤ IO ≤ 1.0A
–2%
2%
–2%
2%
VINDCDC1 = 3.7V to 6V;
0 mA ≤ IO ≤ 1.0A
–1%
1%
–1%
1%
Adjustable output voltage with resistor
divider at DEFDCDC1 MODE = 0
(PWM/PFM)
VINDCDC1 = VDCDC1 +0.4V (min 2.5V)
to 6V; 0mA ≤ IO ≤ 1.6A
–2%
2%
Adjustable output voltage with resistor
divider at DEFDCDC1; MODE = 1
(PWM)
VINDCDC1 = VDCDC1 +0.4V (min 2.5V)
to 6V; 0mA ≤ IO ≤ 1.6A
–1%
1%
Line regulation
VINDCDC1 = VDCDC1 + 0.3V (min. 2.5 V)
to 6V; IO = 10mA
Load regulation
tSS
Soft start ramp time
R(L1)
Internal resistance from L1 to GND
6
V
mA
0
%/V
IO = 10mA to 1.6A
0.25
%/A
VDCDC1 ramping from 5% to 95% of
target value
750
ms
1
MΩ
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SLVSAA7 – MARCH 2010
ELECTRICAL CHARACTERISTICS
VINDCDC1 = VINDCDC2 = VINDCDC3 = VCC = VINLDO = 3.6V, TJ = –40°C to 125°C, typical values are at TA = 25°C
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VDCDC2 STEP-DOWN CONVERTER
VI
Input voltage range, VINDCDC2
IO
Maximum output current
VO = 2.5V
2.5
6
ISD
Shutdown supply current in VINDCDC2
EN_DCDC2 = GND
0.1
1
mA
RDS(on)
P-channel MOSFET on-resistance
VINDCDC2 = VGS = 3.6V
140
300
mΩ
ILP
P-channel leakage current
VINDCDC2 = 6.0V
RDS(on)
N-channel MOSFET on-resistance
VINDCDC2 = VGS = 3.6V
ILN
N-channel leakage current
VDS = 6V
ILIMF
Forward current limit (P- and N-channel) 2.5V < VINDCDC2 < 6V
fS
Oscillator frequency
800
150
2
mA
297
mΩ
mA
7
10
1
1.16
1.29
A
1.95
2.25
2.55
MHz
Fixed output voltage
MODE = 0 (PWM/PFM)
1.8V
VINDCDC2 = 2.5V to 6V; 0 mA ≤ IO ≤ 1.6A
–2%
2%
2.5V
VINDCDC2 = 3V to 6V; 0 mA ≤ IO ≤ 1.6A
–2%
2%
Fixed output voltage
MODE = 1 (PWM)
1.8V
VINDCDC2 = 2.5V to 6V; 0 mA ≤ IO ≤ 1.6A
–2%
2%
2.5V
VINDCDC2 = 3V to 6V; 0 mA ≤ IO ≤ 1.6A
–1%
1%
Adjustable output voltage with resistor
divider at DEFDCDC2 MODE = 0
(PWM)
VINDCDC2 = VDCDC2 + 0.5V (min 2.5V)
to 6V; 0mA ≤ IO ≤ 1.6A
–2%
2%
Adjustable output voltage with resistor
divider at DEFDCDC2; MODE = 1
(PWM)
VINDCDC2 = VDCDC2 + 0.5V (min 2.5V)
to 6V; 0mA ≤ IO ≤ 1.6A
–1%
1%
Line regulation
VINDCDC2 = VDCDC2 + 0.3 V (min. 2.5
V) to 6V; IO = 10mA
Load regulation
tSS
Soft start ramp time
R(L2)
Internal resistance from L2 to GND
VDCDC2
V
mA
0.0
%/V
IO = 10mA to 1.6A
0.25
%/A
VDCDC2 ramping from 5% to 95% of
target value
750
ms
1
MΩ
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ELECTRICAL CHARACTERISTICS
VINDCDC1 = VINDCDC2 = VINDCDC3 = VCC = VINLDO = 3.6V, TJ = –40°C to 125°C, typical values are at TA = 25°C
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VDCDC3 STEP-DOWN CONVERTER
VI
Input voltage range, VINDCDC3
IO
Maximum output current
VO = 1.6V
2.5
6.0
ISD
Shutdown supply current in
VINDCDC3
EN_DCDC3 = GND
0.1
1
mA
RDS(on)
P-channel MOSFET on-resistance
VINDCDC3 = VGS = 3.6V
310
698
mΩ
ILP
P-channel leakage current
VINDCDC3 = 6V
0.1
2
mA
RDS(on)
N-channel MOSFET on-resistance
VINDCDC3 = VGS = 3.6V
220
503
mΩ
ILN
N-channel leakage current
VDS = 6.0V
7
10
mA
ILIMF
Forward current limit (P- and
N-channel)
2.5V < VINDCDC3 < 6V
1.00
1.20
1.40
A
fS
Oscillator frequency
1.95
2.25
2.55
MHz
800
Adjustable output voltage with
resistor divider at DEFDCDC2
MODE = 0 (PWM)
VINDCDC3 = VDCDC3 + 0.5V (min 2.5V) to 6V;
0mA ≤ IO ≤ 0.8A
–2%
2%
Adjustable output voltage with
resistor divider at DEFDCDC2;
MODE = 1 (PWM)
VINDCDC3 = VDCDC3 + 0.5V (min 2.5V) to 6V;
0mA ≤ IO ≤ 0.8A
–1%
1%
Line regulation
VINDCDC3 = VDCDC3 + 0.3V (min. 2.5 V) to
6V; IO = 10mA
Load regulation
tSS
Soft start ramp time
R(L3)
Internal resistance from L3 to GND
VDCDC3
8
V
mA
0.0
%/V
IO = 10mA to 600mA
0.25
%/A
VDCDC3 ramping from 5% to 95% of target
value
750
ms
1
MΩ
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ELECTRICAL CHARACTERISTICS
VINDCDC1 = VINDCDC2 = VINDCDC3 = VCC = VINLDO = 3.6V, TJ = –40°C to 125°C, typical values are at TA = 25°C
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VLDO1 and VLDO2 Low Dropout Regulators
I(q)
Operating quiescent current
Current per LDO into VINLDO
16
33
mA
I(SD)
Shutdown current
Total current into VINLDO, VLDO = 0V
0.6
2
mA
VI
Input voltage range for LDO1, LDO2
1.5
6.5
V
VO
LDO1 output voltage range
1
3.3
V
LDO2 output voltage range
1
3.3
V
(1)
VFB
LDO1 and LDO2 feedback voltage
See
1.0
IO
Maximum output current for LDO1, LDO2
VI = 1.8V, VO = 1.3V
V
IO
Maximum output current for LDO1, LDO2
VI = 1.5V; VO = 1.3V
ISC
LDO1 and LDO2 short circuit current limit
VLDO1 = GND, VLDO2 = GND
400
mA
Minimum voltage drop at LDO1, LDO2
IO = 50mA, VINLDO = 1.8V
120
mV
Minimum voltage drop at LDO1, LDO2
IO = 50mA, VINLDO = 1.5V
150
mV
Minimum voltage drop at LDO1, LDO2
IO = 200mA, VINLDO = 1.8V
300
mV
Output voltage accuracy for LDO1, LDO2
IO = 10mA
–2%
1%
Line regulation for LDO1, LDO2
VINLDO1,2 = VLDO1,2 + 0.5V (min. 2.5V) to 6.5V,
IO = 10mA
–1%
1%
Load regulation for LDO1, LDO2
IO = 0mA to 200mA
–1%
Regulation time for LDO1, LDO2
Load change from 10% to 90%
10
ms
IO = 0mA
1.0
V
200
mA
120
65
mA
1%
Vdd_alive Low Dropout Regulator
Vdd_alive
Vdd_alive LDO output voltage, TPS6502500 to
TPS6502504
IO
Output current for Vdd_alive
I(SC)
Vdd_alive short circuit current limit
Vdd_alive = GND
Output voltage accuracy for Vdd_alive
IO = 0mA
–1%
Line regulation for Vdd_alive
VCC = Vdd_alive + 0.5 V to 6.5 V, IO = 0mA
–1%
Regulation time for Vdd_alive
Load change from 10% to 90%
30
mA
100
mA
1%
1%
10
ms
AnaLogic Signals DEFDCDC1, DEFDCDC2, DEFDCDC3
VIH
High level input voltage
1.3
VCC
VIL
Low level input voltage
0
0.1
V
IH
Input bias current
0.05
mA
0.001
V
THERMAL SHUTDOWN
TSD
Thermal shutdown
Increasing junction temperature
160
°C
Thermal shudown hysteresis
Decreasing junction temperature
20
°C
INTERNAL UNDER VOLTAGE LOCK OUT
UVLO
Internal UVLO
VUVLO_HYST
internal UVLO comparator hysteresis
VCC falling
–3%
2.35
3%
120
V
mV
VOLTAGE DETECTOR COMPARATOR
PWRFAIL_SNS
Comparator threshold
Falling threshold
Hysteresis
VOL
(1)
–2%
1.0
2%
V
40
50
60
mV
Propagation delay
25mV overdrive
10
ms
Power fail output low voltage
IOL = 5 mA
0.3
V
If the feedback voltage is forced higher than above 1.2V, a leakage current into the feedback pin may occur.
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DEVICE INFORMATION
DEFDCDC3
AGND1
PWRFAIL_SNS
Vcc
VINDCDC2
L2
PGND2
VDCDC2
PIN ASSIGNMENTS
32 31 30 29 28 27 26 25
VDCDC3
PGND3
L3
VINDCDC3
VINDCDC1
L1
PGND1
VDCDC1
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
TPS650250
EN_Vdd_alive
MODE
DEFDCDC2
PWRFAIL
EN_DCDC1
EN_DCDC2
EN_DCDC3
EN_LDO
DEFDCDC1
FB_LDO2
FB_LDO1
Vdd_alive
AGND2
VLDO2
VINLDO
VLDO1
9 10 11 12 13 14 15 16
TERMINAL FUNCTIONS
TERMINAL
NAME
NO.
I/O
DESCRIPTION
SWITCHING REGULATOR SECTION
AGND1
31
Analog ground connection. All analog ground pins are connected internally on the chip.
AGND2
13
Analog ground connection. All analog ground pins are connected internally on the chip.
PowerPad
–
VINDCDC1
5
L1
6
VDCDC1
8
PGND1
7
VINDCDC2
28
L2
27
VDCDC2
25
PGND2
26
Connect the power pad to analog ground.
I
Input voltage for VDCDC1 step-down converter. This must be connected to the same voltage supply as
VINDCDC2, VINDCDC3 and VCC.
Switch pin of VDCDC1 converter. The VDCDC1 inductor is connected here.
I
VDCDC1 feedback voltage sense input, connect directly to VDCDC1
Power ground for VDCDC1 converter
I
Input voltage for VDCDC2 step-down converter. This must be connected to the same voltage supply as
VINDCDC1, VINDCDC3 and VCC.
Switch pin of VDCDC2 converter. The VDCDC2 inductor is connected here.
I
VDCDC2 feedback voltage sense input, connect directly to VDCDC2
Power ground for VDCDC2 converter
I
VINDCDC3
4
L3
3
VDCDC3
1
PGND3
2
Vcc
29
I
DEFDCDC1
9
I
DEFDCDC2
22
I
Input voltage for VDCDC3 step-down converter. This must be connected to the same voltage supply as
VINDCDC1, VINDCDC2 and VCC.
Switch pin of VDCDC3 converter. The VDCDC3 inductor is connected here.
I
VDCDC3 feedback voltage sense input, connect directly to VDCDC3
Power ground for VDCDC3 converter
Power supply for digital and analog circuitry of DCDC1, DCDC2 and DCDC3 DC-DC converters. This must be
connected to the same voltage supply as VINDCDC3, VINDCDC1 and VINDCDC2.
Input signal indicating default VDCDC1 voltage, 0 = 2.8V, 1 = 3.3V
This pin can also be connected to a resistor divider between VDCDC1 and GND. In this case the output
voltage of the DCDC1 converter can be set in a range from 0.6V to VINDCDC1
Input signal indicating default VDCDC2 voltage, 0 = 1.8V, 1 = 2.5V
10
This pin can also be connected to a resistor divider between VDCDC2 and GND. In this case the output
voltage of the DCDC2 converter can be set in a range from 0.6V to VINDCDC2.
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TERMINAL FUNCTIONS (continued)
TERMINAL
NAME
NO.
I/O
DESCRIPTION
I
This pin must be connected to a resistor divider between VDCDC3 and GND. The output voltage of the
DCDC3 converter can be set in a range from 0.6V to VINDCDC3.
20
I
VDCDC1 enable pin. A logic high enables the regulator, a logic low disables the regulator.
19
I
VDCDC2 enable pin. A logic high enables the regulator, a logic low disables the regulator.
18
I
VDCDC3 enable pin. A logic high enables the regulator, a logic low disables the regulator.
DEFDCDC3
32
EN_DCDC1
EN_DCDC2
EN_DCDC3
LDO REGULATOR SECTION
VINLDO
15
I
Input voltage for LDO1 and LDO2
VLDO1
16
O
Output voltage of LDO1
VLDO2
14
O
Output voltage of LDO2
EN_LDO
17
I
Enable input for LDO1 and LDO2. Logic high enables the LDOs, logic low disables the LDOs
EN_Vdd_alive
24
I
Enable input for Vdd_alive LDO. Logic high enables the LDO, logic low disables the LDO
Vdd_alive
12
O
Output voltage for Vdd_alive
FB_LDO1
11
I
Feedback pin for LDO1
FB_LDO2
10
I
Feedback pin for LDO2
CONTROL AND I2C SECTION
MODE
23
I
Select between Power Safe Mode and forced PWM Mode for DCDC1, DCDC2 and DCDC3. In Power Safe
Mode PFM is used at light loads, PWM for higher loads. If PIN is set to high level, forced PWM Mode is
selected. If Pin has low level, then Device operates in Power Safe Mode.
PWRFAIL
21
O
Open drain output. Active low when PWRFAIL comparator indicates low VBAT condition.
PWRFAIL_SNS
30
I
Input for the comparator driving the /PWRFAIL output
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FUNCTIONAL BLOCK DIAGRAM
TPS650250
1R
VCC
Vbat
1 mF
VINDCDC1
Vbat
DCDC1 (I/O)
10 mF
STEP-DOWN
CONVERTER
1600 mA
EN_DCDC1
ENABLE
VINDCDC2
Vbat
DCDC2
(memory)
10 mF
STEP-DOWN
CONVERTER
800 mA
EN_DCDC2
ENABLE
VINDCDC3
Vbat
3.3 V / 2.8 V
or adjustable
L1
2.2 mH
VDCDC1
R1
22 mF
DEFDCDC1
PGND1
R2
2.5 V / 1.8 V
or adjustable
L2
2.2 mH
VDCDC2
R3
22 mF
DEFDCDC2
PGND2
R4
L3
10 mF
DCDC3 (core)
2.2 mH
VDCDC3
DEFDCDC3
ENABLE
STEP-DOWN
CONVERTER
800 mA
EN_DCDC3
PGND3
R5
22 mF
R6
MODE
PWM/ PFM
VIN_LDO
VIN
VLDO1
200 mA LDO
EN_LDO
ENABLE
VLDO1
FB_LDO1 R7
2.2 mF
R8
VLDO2
200 mA LDO
VLDO2
FB_LDO2 R9
R10
EN_Vdd_alive
ENABLE
VCC
Vbat
2.2 mF
VLDO3
30 mA LDO
Vdd_alive
1V
2.2 mF
R11
I/O voltage
PWRFAIL_SNS
R12
-
PWRFAIL
R19
+
Vref = 1 V
AGND1
12
AGND2
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TYPICAL CHARACTERISTICS
Parameter Measurement Information
Graphs were taken using the EVM with the following inductor/output capacitor combinations:
CONVERTER
INDUCTOR
OUTPUT CAPACITOR
OUTPUT CAPACITOR VALUE
DCDC1
VLCF4020-3R3
C2012X5R0J226M
22mF
DCDC2
VLCF4020-2R2
C2012X5R0J226M
22mF
DCDC3
LPS3010-222
C2012X5R0J226M
22mF
Table of Graphs
FIGURE
h
Efficiency VDCDC1
vs Load current PWM/PFM; VO = 3.3V
Figure 1
h
Efficiency VDCDC1
vs Load current PWM; VO = 3.3V
Figure 2
h
Efficiency VDCDC2
vs Load current PWM/PFM; VO = 1.8V
Figure 3
h
Efficiency VDCDC2
vs Load current PWM; VO = 1.8V
Figure 4
h
Efficiency VDCDC3
vs Load current PWM/PFM; VO = 1.3V
Figure 5
h
Efficiency VDCDC3
vs Load current PWM; VO = 1.3V
Figure 6
Line transient response VDCDC1
Figure 7
Line transient response VDCDC2
Figure 8
Line transient response VDCDC3
Figure 9
Load transient response VDCDC1
Figure 10
Load transient response VDCDC2
Figure 11
Load transient response VDCDC3
Figure 12
Output voltage ripple DCDC2; PFM mode
Figure 13
Output voltage ripple DCDC2; PWM mode
Figure 14
Load regulation for Vdd_alive
Figure 15
Start-up VDCDC1 to VDCDC3
Figure 16
Start-up LDO1 and LDO2
Figure 17
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DCDC1: EFFICIENCY
vs
OUTPUT CURRENT
100
100
90
90
VI = 3.8 V
80
VI = 4.2 V
70
VI = 5 V
60
50
40
60
VI = 3.8 V
50
VI = 4.2 V
40
30
30
VI = 5 V
TA = 25°C,
VO = 3.3 V,
PFM/PWM Mode
20
10
0
0.1
TA = 25°C,
VO = 3.3 V,
PWM Mode
80
Efficiency - %
70
Efficiency - %
DCDC1: EFFICIENCY
vs
OUTPUT CURRENT
1
10
100
1k
IO - Output Current - mA
20
10
0
0.1
10k
1
10
100
1k
IO - Output Current - mA
Figure 1.
Figure 2.
DCDC2: EFFICIENCY
vs
OUTPUT CURRENT
DCDC2: EFFICIENCY
vs
OUTPUT CURRENT
10k
VI = 2.5 V
VI = 3.8 V
Efficiency - %
Efficiency - %
VI = 3.8 V
VI = 4.2 V
VI = 4.2 V
VI = 2.5 V
VI = 5 V
VI = 5 V
TA = 25oC
VO = 1.8 V
PWM Mode
o
TA = 25 C
VO = 1.8 V
PWM / PFM Mode
0.01
0.1
1
10
100
1k
10 k
0.01
IO - Output Current - mA
Figure 3.
14
0.1
1
10
100
1k
10 k
IO - Output Current - mA
Figure 4.
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DCDC3: EFFICIENCY
vs
OUTPUT CURRENT
DCDC3: EFFICIENCY
vs
OUTPUT CURRENT
100
100
TA = 25°C,
90 VO = 1.5 V,
PWM/PFM Mode
80
80
60
VI = 3 V
50
VI = 3.8 V
30
0
0.01
VI = 3 V
VI = 3.8 V
60
50
VI = 4.2 V
40
VI = 5 V
30
VI = 4.2 V
20
20
10
VI = 2.5 V
70
VI = 2.5 V
Efficiency - %
Efficiency - %
70
40
TA = 25°C,
VO = 1.5 V,
PWM Mode
90
VI = 5 V
0.1
10
1
10
100
IO - Output Current - mA
1k
0
0.01
0.1
1
10
100
IO - Output Current - mA
Figure 5.
Figure 6.
VDCDC1 LINE TRANSIENT RESPONSE
VDCDC2 LINE TRANSIENT RESPONSE
Ch1 = VI
1k
Ch1 = VI
Ch2 = VO
Ch2 = VO
IO = 100 mA
VI = 3.8 V to 4.5 V
VO = 3.3 V
IO = 100 mA
VI = 3 V to 4 V
VO = 1.8 V
PWM Mode
Figure 7.
Figure 8.
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VDCDC3 LINE TRANSIENT RESPONSE
VDCDC1 LOAD TRANSIENT RESPONSE
Ch1 = VI
Ch1 = VI
Ch2 = VO
Ch2 = VO
IO = 160 mA to 14000 mA
VI = 3.3 V
VO = 4.2 V
IO = 100 mA
VI = 3 V to 4 V
VO = 1.375 V
Figure 9.
Figure 10.
VDCDC2 LOAD TRANSIENT RESPONSE
VDCDC3 LOAD TRANSIENT RESPONSE
Ch4 = IO
Ch4 = IO
Ch2 = VO
Ch2 = VO
IO = 100 mA to 900 mA
VO = 1.8 V
IO = 80 mA to 720 mA
VO = 1.375 V
Figure 11.
16
Figure 12.
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VDCDC2 OUTPUT VOLTAGE RIPPLE
VI = 3.8 V
VO = 1.8 V
VDCDC2 OUTPUT VOLTAGE RIPPLE
IO = 1 mA
o
TA = 25 C
PFM Mode
VI = 3.8 V
VO = 1.8 V
IO = 1 mA
TA = 25oC
PWM Mode
Figure 13.
Figure 14.
VDD_ALIVE OUTPUT VOLTAGE
vs
OUTPUT CURRENT
STARTUP VDCDC1, VDCDC2, VDCDC3
1.010
VCC = 3.6 V
ENABLE
VO - Output Voltage - V
1.000
0.990
VDCDC1
0.980
VDCDC2
0.970
0.960
VDCDC3
0.950
0.940
0
5
10
15
20
25
30
IO - Output Current - mA
35
40
Figure 15.
Figure 16.
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STARTUP LDO1 AND LDO2
ENABLE
LDO1
LDO2
Figure 17.
18
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DETAILED DESCRIPTION
STEP-DOWN CONVERTERS, VDCDC1, VDCDC2 AND VDCDC3
The TPS650250 incorporates three synchronous step-down converters operating typically at 2.25MHz fixed
frequency PWM (Pulse Width Modulation) at moderate to heavy load currents. At light load currents the
converters automatically enter Power Save Mode and operate with PFM (Pulse Frequency Modulation).
VDCDC1 delivers up to 1.6A, VDCDC2 and VDCDC3 are capable of delivering up to 0.8A of output current.
The converter output voltages can be programmed via the DEFDCDC1, DEFDCDC2 and DEFDCDC3 pins. The
pins can either be connected to GND, VCC or to a resistor divider between the output voltage and GND. The
VDCDC1 converter defaults to 2.8V or 3.3V depending on the DEFDCDC1 configuration pin, if DEFDCDC1 is
tied to ground the default is 2.80V, if it is tied to VCC the default is 3.3V. When the DEFDCDC1 pin is connected
to a resistor divider, the output voltage can be set in the range of 0.6V to VINDCDC1 V. Reference the section
on Output Voltage Selection for details on setting the output voltage range.
The VDCDC2 converter defaults to 1.8V or 2.5V depending on the DEFDCDC2 configuration pin, if DEFDCDC2
is tied to ground the default is 1.8V, if it is tied to VCC the default is 2.5V. When the DEFDCDC2 pin is
connected to a resistor divider, the output voltage can be set in the range of 0.6V to VINDCDC2 V.
On the DEFDCDC3 pin for the VDCDC3 converter, a resistor divider must be connected to set the output
voltage. This pin does not accept a logic signal like DEFDCDC1 or DEFDCDC2. The value for the resistor divider
can be changed during operation, so voltage scaling can be implemented by changing the resistor value.
During PWM operation the converters use a unique fast response voltage mode controller scheme with input
voltage feed-forward to achieve good line and load regulation allowing the use of small ceramic input and output
capacitors. At the beginning of each clock cycle initiated by the clock signal, the P-channel MOSFET switch is
turned on and the inductor current ramps up until the comparator trips and the control logic turns off the switch.
The current limit comparator also turns off the switch in case the current limit of the P-channel switch is
exceeded. After the adaptive dead time used to prevent shoot through current, the N-channel MOSFET rectifier
is turned on and the inductor current ramps down. The next cycle is initiated by the clock signal again turning off
the N-channel rectifier and turning on the P-channel switch.
The three DC/DC converters operate synchronized to each other, with the VDCDC1 converter as the master. A
180° phase shift between the VDCDC1 switch turn on and the VDCDC2 and a further 90° shift to the VDCDC3
switch turn on decreases the input RMS current and smaller input capacitors can be used. This is optimized for a
typical application where the VDCDC1 converter regulates a Li-Ion battery voltage of 3.7V to 3.3V, the VDCDC2
converter from 3.7V to 2.5V and the VDCDC3 converter from 3.7V to 1.5V.
POWER SAVE MODE OPERATION
As the load current decreases, the converters enter Power Save Mode operation. During Power Save Mode the
converters operate in a burst mode (PFM mode) with a frequency between 1.125MHz and 2.25MHz for one burst
cycle. However, the frequency between different burst cycles depends on the actual load current and is typically
far less than the switching frequency, with a minimum quiescent current to maintain high efficiency.
In order to optimize the converter efficiency at light load the average current is monitored and if in PWM mode
the inductor current remains below a certain threshold, then Power Save Mode is entered. The typical threshold
to enter Power Save Mode can be calculated as follows:
I PFMDCDC1enter + VINDCDC 1
24 W
I PFMDCDC2enter + VINDCDC 2
26 W
I PFMDCDC3leave + VINDCDC 3
39 W
(1)
During Power Save Mode the output voltage is monitored with a comparator and by maximum skip burst width.
As the output voltage falls below the threshold, set to the nominal VO, the P-channel switch turns on and the
converter effectively delivers a constant current as defined below.
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I PFMDCDC1leave + VINDCDC 1
18 W
I PFMDCDC2leave + VINDCDC 2
20 W
I PFMDCDC3enter + VINDCDC 3
29 W
(2)
If the load is below the delivered current then the output voltage rises until the same threshold is crossed in the
other direction. All switching activity ceases, reducing the quiescent current to a minimum until the output voltage
has again dropped below the threshold. The power save mode is exited, and the converter returns to PWM mode
if either of the following conditions are met:
1. The output voltage drops 2% below the nominal VO due to increased load current
2. The PFM burst time exceeds 16 × 1/fs (7.1ms typical)
These control methods reduce the quiescent current to typically 14mA per converter and the switching activity to
a minimum thus achieving the highest converter efficiency. Setting the comparator thresholds at the nominal
output voltage at light load current results in a very low output voltage ripple. The ripple depends on the
comparator delay and the size of the output capacitor; increasing capacitor values makes the output ripple tend
to zero. Power Save Mode can be disabled by pulling the MODE pin high. This forces all DC/DC converters into
fixed frequency PWM mode.
SOFT START
Each of the three converters has an internal soft start circuit that limits the inrush current during start-up. The soft
start is realized by using a very low current to initially charge the internal compensation capacitor. The soft start
time is typically 750ms if the output voltage ramps from 5% to 95% of the final target value. If the output is
already pre-charged to some voltage when the converter is enabled, then this time is reduced proportionally.
There is a short delay of typically 170ms between the converter being enabled and switching activity actually
starting. This is to allow the converter to bias itself properly, to recognize if the output is pre-charged, and if so, to
prevent discharging of the output while the internal soft start ramp catches up with the output voltage.
100% DUTY CYCLE LOW DROPOUT OPERATION
The TPS650250x converters offer a low input to output voltage difference while still maintaining operation with
the use of the 100% duty cycle mode. In this mode the P-channel switch is constantly turned on. This is
particularly useful in battery-powered applications to achieve the longest operation time by taking full advantage
of the whole battery voltage range. The minimum input voltage required to maintain DC regulation depends on
the load current and output voltage and can be calculated as:
Vin min + Vout min ) Iout max
ǒRDSonmax ) R LǓ
(3)
With:
Ioutmax = Maximum load current (note: ripple current in the inductor is zero under these conditions)
RDSonmax = Maximum P-channel switch RDSon
RL = DC resistance of the inductor
Voutmin = Nominal output voltage minus 2% tolerance limit
LOW DROPOUT VOLTAGE REGULATORS
The low dropout voltage regulators are designed to operate well with low value ceramic input and output
capacitors. They operate with input voltages down to 1.5V. The LDOs offer a maximum dropout voltage of
300mV at the rated output current. Each LDO sports a current limit feature. Both LDOs are enabled by the
EN_LDO pin. The LDOs also have reverse conduction prevention. This allows the possibility to connect external
regulators in parallel in systems with a backup battery. The TPS650250 step-down and LDO voltage regulators
automatically power down when the Vcc voltage drops below the UVLO threshold or when the junction
temperature rises above 160°C.
20
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UNDERVOLTAGE LOCKOUT
The undervoltage lockout circuit for the five regulators on the TPS650250x prevents the device from
malfunctioning at low input voltages and from excessive discharge of the battery. It disables the converters and
LDOs. The UVLO circuit monitors the Vcc pin; the threshold is set internally to 2.35V with 5% (120mV)
hysteresis. Note that when any of the DC/DC converters are running there is an input current at the Vcc pin,
which can be up to 3mA when all three converters are running in PWM mode. This current needs to be taken
into consideration if an external RC filter is used at the Vcc pin to remove switching noise from the TPS650250x
internal analog circuitry supply. See the Vcc-Filter section for details on the external RC filter.
POWER-UP SEQUENCING
The TPS650250x power-up sequencing is designed to be entirely flexible and customer driven; this is achieved
simply by providing separate enable pins for each switch-mode converter and a common enable signal for LDO1
and LDO2. The relevant control pins are described in Table 1.
Table 1. Control Pins for DCDC Converters
PIN NAME
INPUT/
OUTPUT
DEFDCDC3
I
Defines the default voltage of the VDCDC3 switching converter set with an eternal resistor divider.
DEFDCDC2
I
Defines the default voltage of the VDCDC2 switching converter. DEFDCDC2 = 0 defaults VDCDC2 to 1.8V,
DEFDCDC2 = VCC defaults VDCDC2 to 2.5V.
DEFDCDC1
I
Defines the default voltage of the VDCDC1 switching converter. DEFDCDC1 = 0 defaults VDCDC1 to 2.80V,
DEFDCDC1 = VCC defaults VDCDC1 to 3.3V.
EN_DCDC3
I
Set EN_DCDC3 = 0 to disable or EN_DCDC3 = 1 to enable the VDCDC3 converter
EN_DCDC2
I
Set EN_DCDC2 = 0 to disable or EN_DCDC2 = 1 to enable the VDCDC2 converter
EN_DCDC1
I
Set EN_DCDC1 = 0 to disable or EN_DCDC1 = 1 to enable the VDCDC1 converter
FUNCTION
PWRFAIL
The PWRFAIL signal is generated by a voltage detector at the PWRFAIL_SNS input. The input signal is
compared to a 1V threshold (falling edge) with 5% (50mV) hysteresis. PWRFAIL is an open drain output which is
actively low when the input voltage at PWRFAIL_SNS is below the threshold.
DESIGN PROCEDURE
Inductor Selection for the dcdc Converters
The three converters operate with 2.2uH output inductors. Larger or smaller inductor values can be used to
optimize performance of the device for specific conditions. The selected inductor has to be rated for its dc
resistance and saturation current. The dc resistance of the inductor influences directly the efficiency of the
converter. Therefore, an inductor with the lowest dc resistance should be selected for the highest efficiency.
For a fast transient response, a 2.2mH inductor in combination with a 22mF output capacitor is recommended. For
an output voltage above 2.8V, an inductor value of 3.3mH minimum is required. Lower values result in an
increased output voltage ripple in PFM mode. The minimum inductor value is 1.5mH, but an output capacitor of
22mF minimum is needed in this case.
Equation 4 calculates the maximum inductor current under static load conditions. The saturation current of the
inductor should be rated higher than the maximum inductor current as calculated with Equation 4. This is
recommended because during heavy load transient the inductor current rises above the calculated value.
1 * Vout
DI
Vin
DI L + Vout
I Lmax + I outmax ) L
2
L ƒ
(4)
With:
f = Switching frequency (2.25 MHz typical)
L = Inductor value
ΔIL = Peak-to-peak inductor ripple current
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ILmax = Maximum inductor current
The highest inductor current occurs at maximum Vin.
Open core inductors have a soft saturation characteristic and they can usually handle higher inductor currents
versus a comparable shielded inductor.
A more conservative approach is to select the inductor current rating just for the maximum switch current of the
corresponding converter. Consideration must be given to the difference in the core material from inductor to
inductor which has an impact on efficiency especially at high switching frequencies. See Table 2 and the typical
applications for possible inductors.
Table 2. Tested Inductors
DEVICE
INDUCTOR
VALUE
TYPE
COMPONENT
SUPPLIER
3.3mH
LPS3015-332 (output current up to 1A)
Coilcraft
2.2mH
LPS3015-222 (output current up to 1A)
Coilcraft
3.3mH
VLCF4020T-3R3N1R5
TDK
2.2mH
VLCF4020T-2R2N1R7
TDK
2.2mH
LPS3010-222
Coilcraft
2.2mH
LPS3015-222
Coilcraft
2.2mH
VLCF4020-2R2
TDK
DCDC3 converter
Output Capacitor Selection
The advanced Fast Response voltage mode control scheme of the inductive converters implemented in the
TPS650250x allows the use of small ceramic capacitors with a typical value of 10uF for each converter, without
having large output voltage under and overshoots during heavy load transients. Ceramic capacitors having low
ESR values have the lowest output voltage ripple and are recommended. Refer to Table 3 for recommended
components.
If ceramic output capacitors are used, the capacitor RMS ripple current rating will always meet the application
requirements. For completeness, the RMS ripple current is calculated as:
1 * Vout
1
Vin
I RMSCout + Vout
L ƒ
2 Ǹ3
(5)
At nominal load current the inductive converters operate in PWM mode and the overall output voltage ripple is
the sum of the voltage spike caused by the output capacitor ESR plus the voltage ripple caused by charging and
discharging the output capacitor:
1 * Vout
1
Vin
DVout + Vout
) ESR
8 Cout ƒ
L ƒ
(6)
ǒ
Ǔ
Where the highest output voltage ripple occurs at the highest input voltage, Vin.
At light load currents the converters operate in Power Save Mode and output voltage ripple is dependent on the
output capacitor value. The output voltage ripple is set by the internal comparator delay and the external
capacitor. Typical output voltage ripple is less than 1% of the nominal output voltage.
Input Capacitor Selection
Because of the nature of the buck converter having a pulsating input current, a low ESR input capacitor is
required for best input voltage filtering and minimizing interference with other circuits caused by high input
voltage spikes. Each dcdc converter requires a 10uF ceramic input capacitor on its input pin VINDCDCx. The
input capacitor can be increased without any limit for better input voltage filtering. The Vcc pin should be
separated from the input for the DC/DC converters. A filter resistor of up to 10Ω and a 1mF capacitor should be
used for decoupling the Vcc pin from switching noise. Note that the filter resistor may affect the UVLO threshold
since up to 3mA can flow via this resistor into the Vcc pin when all converters are running in PWM mode.
22
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TPS650250-Q1
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SLVSAA7 – MARCH 2010
Table 3. Possible Capacitors
CAPACITOR
VALUE
CASE SIZE
22mF
1206
TDK
C3216X5R0J226M
Ceramic
22mF
1206
Taiyo Yuden
JMK316BJ226ML
Ceramic
22mF
0805
TDK
C2012X5R0J226MT
Ceramic
22mF
0805
Taiyo Yuden
JMK212BJ226MG
Ceramic
10mF
0805
Taiyo Yuden
JMK212BJ106M
Ceramic
10mF
0805
TDK
C2012X5R0J106M
Ceramic
COMPONENT SUPPLIER
COMMENTS
Output Voltage Selection
The DEFDCDC1, DEFDCDC2, and DEFDCDC3 pins are used to set the output voltage for each step-down
converter. See Table 4 for the default voltages if the pins are pulled to GND or to Vcc.
Table 4. Voltage Options
PIN
LEVEL
DEFDCDC1
DEFAULT OUTPUT VOLTAGE
VCC
3.3V
GND
2.80V
DEFDCDC2
VCC
2.5V
GND
1.8V
DEFDCDC3
external voltage divider
0.6V to VinDCDC3
If a different voltage is needed, an external resistor divider can be added to the DEFDCDC1 or DEFDCDC2 pin
as shown below:
10 R
Vbat
VCC
1 mF
VDCDC1
L1
VINDCDC1
CIN
VOUT
L
COUT
EN_DCDC1
R1
DEFDCDC1
R2
AGND
PGND
When a resistor divider is connected to DEFDCDC1 or DEFDCDC2, the output voltage can be set from 0.6V up
to the input voltage Vbat. The total resistance (R1+R2) of the voltage divider should be kept in the 1MΩ range in
order to maintain a high efficiency at light load. VDEFDCDCx = 0.6V
V OUT + VDEFDCDCx
R1 ) R2
R2
R1 + R2
ǒ
V OUT
VDEFDCDCx
Ǔ
* R2
Voltage Change on VDCDC3
The output voltage of VDCDC3 is set with an external resistor divider at DEFDCDC3. This pin must not be
connected to GND or VINDCDC3. The value of the resistor divider can be changed during operation to allow
dynamic voltage scaling.
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23
TPS650250-Q1
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Vdd_alive Output
The Vdd_alive LDO is typically connected to the Vdd_alive input of the Samsung application processor. It
provides an output voltage of 1V at 30mA. It is recommended to add a capacitor of 2.2mF minimum to the
Vdd_alive pin. The LDO can be disabled by pulling the EN_Vdd_alive pin to GND.
LDO1 and LDO2
The LDOs in the TPS650250 are general purpose LDOs which are stable using ceramics capacitors. The
minimum output capacitor required is 2.2mF. The LDOs output voltage can be changed to different voltages
between 1V and 3.3V using an external resistor divider. Therefore they can also be used as general purpose
LDOs in the application. The supply voltage for the LDOs needs to be connected to the VINLDO pin, giving the
flexibility to connect the lowest voltage available in the system and therefore providing the highest efficiency.
The total resistance (R5+R6) of the voltage divider should be kept in the 1MΩ range in order to maintain high
efficiency at light load. VFBLDOx= 1.0V.
V OUT + VFBLDOx
R5 ) R6
R6
R5 + R6
ǒ
V OUT
VFBLDOx
Ǔ
* R6
Vcc-Filter
An RC filter connected at the Vcc input is used to keep noise from the internal supply for the bandgap and other
analog circuitry. A typical value of 1Ω and 1mF is used to filter the switching spikes, generated by the DC/DC
converters. A larger resistor than 10Ω should not be used because the current into Vcc of up to 2.5mA causes a
voltage drop at the resistor causing the undervoltage lockout circuitry connected at Vcc internally to switch off too
early.
24
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TPS650250-Q1
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SLVSAA7 – MARCH 2010
APPLICATION INFORMATION
TYPICAL CONFIGURATION FOR THE SAMSUNG PROCESSOR S3C6400-533MHz
The typical configuration for the Samsung processor S3C6400-533MHz is shown in Figure 18.
TPS 650250
Vcc
VIN
1 mF
DCDC 1
1600 mA
VINDCDC1
VIN
L1
VDDHI (3.3V)
2.2 mH
VDDLCD (3.3V)
VDDPCM (3.3V)
VINDCDC 2
DCDC 2
800 mA
10 mF
VDDSYS (3.3V)
10 mF
VDCDC2
VDD _MEM 0 (1.8V)
VDD _MEM 1 (1.8V)
VINDCDC 3
L3
10 mF
DCDC 3
800 mA
2.2 mH
VDDARM (0.9V / 1.1V)
VDCDC3
10 mF
R5
DEFDCDC3
DEFDCDC1
VIN
VDDMMC (3.3V)
VDCDC 1
L2
VIN
VDDEXT (3.3V)
10 mF
10 mF
VIN
S3C6400 533 MHz
3.3 mH
R6
DEFDCDC2
VLDO2
300 kW
LDO 2
200 mA
VDDADC (3.3V)
2.2 mF
VDDDAC (3.3V)
VDDOTG (3.3V)
VDDUH (3.3V )
FB_LDO 2
130 kW
VLDO1
EN_DCDC 1
LDO 1
200 mA
EN_DCDC 2
EN_DCDC 3
VIN
33 kW
VDDOTGI (1.1V)
2.2 mF
FB_LDO1
330 kW
VINLDO 1/2
1 mF
Vdd_alive 1 V
VIN VIN
VDDALIVE
1 mF
EN_LDO 1/2
VIO
EN_VDDalive
1M
R2
PWRFAIL
PWRFAIL_SNS
-
R3
1V
+
GND
APLL (1 V)
AGND, PowerPAD
EPLL (1 V)
VIN
VIN
10 mF
2.2 mH
MPLL (1 V)
VDDINT (1 V)
SW
EN
EN
MODE
TPS62260
FB 22 pF
GND
100 kW
10 mF
150 kW
Figure 18. Samsung Processor Configuration
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25
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)
TPS650250QRHBRQ1
ACTIVE
VQFN
RHB
32
3000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
TPS
650250Q
(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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