RT9040 - Richtek

®
RT9040
DDR Termination Regulator
General Description
Features
The RT9040 is a sink/source tracking termination regulator.
It is specifically designed for low-cost and low-external
component count systems. The RT9040 possesses a high
speed operating amplifier that provides fast load transient
response and only requires a minimum 20μF of ceramic
output capacitance. The RT9040 supports remote sensing
functions and all features required to power the DDRI /
DDRII / DDRIII and Low Power DDRIII VTT bus termination
according to the JEDEC specification. In addition, the
RT9040 provides an open drain PGOOD signal to monitor
the output regulation and an EN signal that can be used
to discharge VTT during S3 (suspend to RAM) for DDR
applications .

VIN Input Voltage Range : 1.1V to 3.5V

VCNTL Input Voltage Range : 2.375V to 5.5V
MLCC Stable
PGOOD to Monitor Output Regulation
±10mA Reference (REFOUT)
Meet DDRI, DDRII JEDEC Spec Supports DDRIII, Low
Power DDRIII VTT Application
Soft Start Function UVLO and OCP
UVLO and OCP Protection
Thermal Shutdown
RoHS Compliant and Halogen Free
The RT9040 is available in the thermal efficient WDFN10L 3x3 package.
Ordering Information
(2)







Application


Notebook/Desktop/Server
Telecom/Datacom, GSM Base Station, LCD-TV/PDPTV ,Copier/Printer, Set-Top Box
Pin Configurations
(TOP VIEW)
Pin 1 Orientation
(2) : Quadrant 2, Follow EIA-481-D
REFIN
VIN
VOUT
PGND
SENSE
Package Type
QW : WDFN-10L 3x3 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)

RoHS compliant and compatible with the current require-
4
5
11
10
9
8
7
6
VCNTL
PGOOD
GND
EN
REFOUT
WDFN-10L 3x3
Marking Information
RT9040GQW(2)
Note :
Richtek products are :
1
2
3
GND
RT9040

G4= : Product Code
G4=YM
DNN
YMDNN : Date Code
ments of IPC/JEDEC J-STD-020.

Suitable for use in SnPb or Pb-free soldering processes.
RT9040ZQW(2)
G4 : Product Code
G4 YM
DNN
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9040-04 January 2014
YMDNN : Date Code
is a registered trademark of Richtek Technology Corporation.
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1
RT9040
Typical Application Circuit
RT9040
2
VIN
R1
10k
1
C1
10µF x 2
R2
10k
C3
0.1µF
Chip Enable
10
R3
100k
REFIN
PGOOD
C2
1nF
6
REFOUT
VCNTL
VIN
9
PGND
7 EN
GND
VCNTL
2.5V/3.3V/5V
Power Good Indicator
VOUT 3
SENSE 5
REFOUT
C4
4.7µF
VOUT
C5
10µF x 3
4
8, 11 (Exposed Pad)
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
REFIN
Reference Input.
2
VIN
Supply Voltage for the LDO.
3
VOUT
Power Output for the LDO.
4
PGND
5
SENSE
6
REFOUT
Power Ground Output for the LDO.
Voltage Sense Output for the LDO. Connect to positive terminal of the output
capacitor or the load.
Reference Output. Connect to GND through 0.1uF ceramic capacitor.
7
EN
Chip Enable. For DDR VTT application, connect EN to SLP_S3. For any other
application(s), use EN as the ON/OFF function.
Signal Ground. Connect to negative terminal of the output capacitor. The exposed
pad must be soldered to a large PCB and connected to GND for maximum power
dissipation.
PGOOD Output. Indicates regulation. Connect to an internal open drain
N-MOSFET.
2.5V, 3.3V or 5V power supply. A ceramic decoupling capacitor with a value
between 1F and 4.7F is required.
8,
GND
11 (Exposed Pad)
9
PGOOD
10
VCNTL
Function Block Diagram
EN VCNTL
REFIN
Control
Logic
Thermal
Protection
VIN
+
OCP
-
Buffer
SENSE
REFOUT
VOUT
OP
+
PGOOD
Power
Good
GND
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2
Driver
+
OCP
-
PGND
is a registered trademark of Richtek Technology Corporation.
DS9040-04 January 2014
RT9040
Absolute Maximum Ratings








(Note 1)
Supply Input Voltage, VIN, REFIN, VCNTL -------------------------------------------------------------------------Enable Voltage, EN ------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
WDFN-10L 3x3 ------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2)
WDFN-10L 3x3, θJA ------------------------------------------------------------------------------------------------------WDFN-10L 3x3, θJC ------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3)
HBM (Human Body Model) ---------------------------------------------------------------------------------------------MM (Machine Model) -----------------------------------------------------------------------------------------------------
Recommended Operating Conditions




6V
6V
1.429W
70°C/W
8.2°C/W
260°C
150°C
−65°C to 150°C
2kV
200V
(Note 4)
Supply Input Voltage, VCNTL ------------------------------------------------------------------------------------------ 2.375V to 5.5V
Supply Input Voltage, VIN ------------------------------------------------------------------------------------------------ 1.1V to 3.5V
Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VIN = 1.8V, VEN = VCNTL = 3.3V, VREFIN = 0.9V, VSENSE = 0.9V, COUT = 10uF x 3, TA = 25°C, unless otherwise specification)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
VEN = 3.3V, No Load
--
0.9
2
mA
VEN = 0V, VREFIN = 0, No Load
--
65
80
VEN = 0V, VREFIN > 0.4V, No Load
--
200
500
A
Supply Current
VCNTL Supply Current
IVCNTL
VCNTL Shutdown
Current
ISHDN_VCNTL
VIN Supply Current
IVIN
VEN = 3.3V, No Load
--
--
2
mA
VIN Shutdown Current
ISHDN_VIN
VEN = 0V, No Load
--
0.1
50
A
IREFIN
VEN = 3.3 V
--
--
1
A
VIN = 1.5 V, VREFOUT = 0.75V
(DDRIII), IOUT = 0A
-10
-10
-10
1.25
-0.9
-0.75
--
-10
-10
-10
V
mV
V
mV
V
mV
–2A < IOUT < 2A
15
--
15
mV
Input Current
REFIN Input Current
Output
VIN = 2.5 V, VREFOUT = 1.25 V
(DDRI), IOUT = 0A
Offset Voltage of Output
DC Voltage
VOUT Load Regulation
VVOTOL
VLOAD
VIN = 1.8 V, VREFOUT = 0.9V
(DDRII), I OUT = 0A
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9040-04 January 2014
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RT9040
Parameter
Symbol
VOUT Source Current
I LIM_VOUT_sr
Limit
VOUT Sink Current
I LIM_VOUT_sk
Limit
VOUT Discharge
RDISCHARGE
Resistance
Power Good Comparator
VOUT PGOOD
Threshold
V TH_PGOOD
PGOOD Startup Delay
Tpgdelay1
Output Low Voltage
V LOW_PGOOD
PGOOD Bad Delay
Tpgdealy2
Leakage Current
I LEAKAGE_PGOOD
Test Conditions
VCNTL = 5V (V OUT in PGOOD
window)
VCNTL = 5V (V OUT in PGOOD
window)
VREFIN = 0V, VOUT = 0.3V,
VEN = 0V
Min
Typ
Max
Unit
3.5
--
5.5
A
3.5
--
5.5
A
--
18
25

23.5
20
17.5
PGOOD Hysteresis
--
5
--
Startup rising edge, VSENSE within
15% of REFOUT
--
2
--
ms
--
--
0.4
V
--
10
--
s
--
--
1
A
0.5
--
1.8
V
360
390
420
--
20
--
15
--
15
15
--
15
15
--
15
VREFOUT = 0V
10
40
--
mA
VREFOUT = VIN
10
40
--
mA
Wake up
2.2
2.3
2.375
V
--
50
--
mV
PGOOD window lower threshold
with respect to REFOUT
ISINK = 4mA
VSENSE is outside of the ±20%
PGOOD window
VSENSE = VREFIN (PGOOD high
impedance), PGOOD = VCNTL +
0.2 V
%
REFIN and REFOUT
REFIN Voltage Range
V REFIN
REFIN Under Voltage
Lockout
V UVLO_REFIN
REFOUT Voltage
Tolerance to VREFIN
V TOL_REFOUT
REFOUT Source
I LIM_REFOUT_sr
Current Limit
REFOUT Sink Current
I LIM_REFOUT_sk
Limit
UVLO / EN Logic Threshold
UVLO Threshold
High-Level Input
Voltage
Low-Level Input
Voltage
Hysteresis Voltage
Logic Input Leakage
Current
Thermal Shutdown
Thermal Shutdown
Threshold
V UVLO_VCNTL
REFIN Rising
Hysteresis
10mA < IREFOUT < 10mA, VREFIN
= 1.25 V
10mA < IREFOUT < 10mA, VREFIN
= 0.9 V
10mA < IREFOUT < 10mA, VREFIN
= 0.75V
Hysteresis
mV
V IN_H
Enable
1.7
--
--
V
V IN_L
Enable
--
--
0.3
V
V EN_hys
Enable
--
0.5
--
V
I LEAKAGE_EN
Enable
1
--
1
A
Shutdown Temperature
--
160
--
Hysteresis
--
25
--
T SD
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mV
C
is a registered trademark of Richtek Technology Corporation.
DS9040-04 January 2014
RT9040
Note 1. Stresses beyond those listed “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 in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is
measured at the exposed pad of the package.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9040-04 January 2014
is a registered trademark of Richtek Technology Corporation.
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RT9040
Typical Operating Characteristics
Shutdown Current vs. Temperature
80
1100
79
Shutdown Current (µA)1
Supply Current (µA)
Supply Current vs. Temperature
1150
1050
1000
950
900
850
800
750
78
77
76
75
74
73
700
VIN = 2.5V, REFIN = 0V, VCNTL = 5V, VEN = 0V
VIN = 2.5V, REFIN = 1.25V, VCNTL = VEN = 5V
650
-40 -25 -10
5
20
35
50
65
80
72
-40 -25 -10
95 110 125
5
50
65
80
95 110 125
DDRI Output Voltage vs. Load Current
Standby Current vs. Temperature
364
1.2495
362
VCNTL = 3.3V
1.2490
360
358
Output Voltage (V)
Standby Current (µA)
35
Temperature (°C)
Temperature (°C)
VIN = 1.5V
VIN = 1.8V
VIN = 2.5V
356
354
352
350
348
1.2485
1.2480
1.2475
1.2470
1.2465
VCNTL = 5V
1.2460
346
VIN = 2.5V, REFIN = 1.25V, VEN = VCNTL
VCNTL = 5V, VEN = 0V
344
1.2455
-40 -25 -10
5
20
35
50
65
80
95 110 125
0
0.25
0.5
Temperature (°C)
0.75
1
1.25
1.5
1.75
2
Load Current (A)
DDRII Output Voltage vs. Load Current
DDRIII Output Voltage vs. Load Current
0.74365
0.8990
VCNTL = 3.3V
0.8985
VCNTL = 5V
0.74360
0.8980
Output Voltage (V)
Output Voltage (V)
20
0.8975
0.8970
0.8965
VCNTL = 5V
0.8960
0.74355
0.74350
0.74345
VCNTL = 3.3V
0.74340
0.8955
VIN = 1.5V, REFIN = 0.75V, VEN = VCNTL
VIN = 1.8V, REFIN = 0.9V, VEN = VCNTL
0.74335
0.8950
0
0.25
0.5
0.75
1
1.25
1.5
1.75
Load Current (A)
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2
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
Load Current (A)
is a registered trademark of Richtek Technology Corporation.
DS9040-04 January 2014
RT9040
DDRI Output Voltage vs. Load Current
DDRII Output Voltage vs. Load Current
1.2464
0.8964
0.8962
VCNTL = 5V
Output Voltage (V)
Output Voltage (V)
1.2462
1.2460
1.2458
VCNTL = 3.3V
1.2456
1.2454
VCNTL = 5V
0.8960
VCNTL = 3.3V
0.8958
0.8956
0.8954
1.2452
VIN = 2.5V, REFIN = 1.25V, VEN = VCNTL
VIN = 1.8V, REFIN = 0.9V, VEN = VCNTL
0.8952
1.2450
-1.5
-1.25
-1
-0.75
-0.5
-0.25
-1.5
0
-1.25
-1
-0.75
-0.5
Load Current (A)
Load Current (A)
DDRIII Output Voltage vs. Load Current
Power On
-0.25
0
0.7462
VIN = 1.8V, REFIN = 0.9V
Output Voltage (V)
0.7460
REFOUT
(1V/Div)
VCNTL = 5V
0.7458
VCNTL = 3.3V
0.7456
VEN
(5V/Div)
0.7454
0.7452
VOUT
(1V/Div)
0.7450
PGOOD
(5V/Div)
VIN = 1.5V, REFIN = 0.75V, VEN = VCNTL
ENON = 3.3V, VCNTL = 3.3V, No Load
0.7448
-1.5
-1.25
-1
-0.75
-0.5
-0.25
Time (400μs/Div)
0
Load Current (A)
1.25VOUT @ ±1.5A Transient Response
Power Off
VIN = 1.8V, REFIN = 0.9V
REFOUT
(1V/Div)
VIN = 2.5V, REFIN = 1.25V
ΔVOUT
(20mV/Div)
VEN
(5V/Div)
VOUT
(1V/Div)
PGOOD
(5V/Div)
IOUT
(2A/Div)
ENOFF = 0V, VCNTL = 3.3V, No Load
Time (200ns/Div)
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DS9040-04 January 2014
VCNTL = VEN = 3.3V, COUT = 10μF x 3
Time (200μs/Div)
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RT9040
0.75VOUT @ ±1.5A Transient Response
0.9VOUT @ ±1.5A Transient Response
VIN = 1.5V, REFIN = 0.75V
VIN = 1.8V, REFIN = 0.9V
ΔVOUT
(20mV/Div)
ΔVOUT
(20mV/Div)
IOUT
(2A/Div)
IOUT
(2A/Div)
VCNTL = VEN = 3.3V, COUT = 10μF x 3
Time (200μs/Div)
VCNTL = VEN = 3.3V, COUT = 10μF x 3
Time (200μs/Div)
1.25VREFOUT @ ±15mA Transient Response
VIN = 2.5V, REFIN = 1.25V
ΔVREFOUT
(10mV/Div)
IOUT
(20mA/Div)
VCNTL = VEN = 3.3V, COUT = 0.1μF
Time (400μs/Div)
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is a registered trademark of Richtek Technology Corporation.
DS9040-04 January 2014
RT9040
Application Information
The RT9040 is a sink/source tracking termination regulator.
Operation State Setting
It is specifically designed for low-cost and low-external
component count systems such as notebook PC
applications. The RT9040 possesses a high speed
operating amplifier that provides fast load transient response
and only requires a 10μF ceramic input capacitor and two
10μF ceramic output capacitors.
The EN pin could be connected to SLP_S3 signal for DDR
VTT application. Both VOUT and REFOUT are turned on
at normal state( EN = High, REFIN >0.39V). In standby
state( EN = Low, REFIN >0.39V), REFOUT voltage will be
kept alive to discharge VOUT voltage via internal circuit
and left VOUT high impedance. When EN = Low and REFIN
<0.39V, the RT9040 enter shutdown state, both VOUT
and REFOUT will be turned off and discharged to ground
via internal MOSFETs. Table 1 summarizes the abovementioned operation state setting, and figure 1 shows a
typical start up and shutdown timing diagram.
REFOUT Regulator
REFOUT is a reference output voltage with source/sink
current capability up to 10mA. To ensure stable operation,
a 0.1μF ceramic capacitor connected between REFOUT
and GND is recommended.
Table1. Operation State Settling
Capacitor Selection
To achieve best performance of the RT9040, it is
recommended to follow the following descriptions for
capacitor selection.
STATE
Normal
Standby
Shutdown
EN
High
Low
Low
REFIN
> 0.39V
> 0.39V
< 0.39V
VOUT
ON
OFF
OFF
REFOUT
ON
ON
OFF
VCNTL Capacitor :
Add a ceramic capacitor 4.7μF placed to VCNTL pin as
close as possible to stabilize the supply voltage (2.5V,
3.3V or 5.0V rail) from any parasitic impedance from the
supply.
VIN Capacitor :
Good bypassing is recommended from VIN to GND to
improve transient response. It is recommended to place
two 10μF or greater input capacitor located as close as
possible to the IC the capacitor must be placed at less
than 0.5 inch from the VIN pin.
VCNTL
VIN
0.37V
0.39V
REFIN
REFOUT
EN
VOUT
PGOOD
2ms
Figure 1. Typical Start Up and Shutdown Timing Diagram
VOUT Capacitor :
For stable operation, the total capacitance of the VTT output
terminal must be greater than 20μF. The RT9040 is
designed specifically to work with low ESR ceramic output
capacitor in space-saving and performance consideration.
Larger output capacitance can reduce the noise and
improve load transient response, stability and PSRR.
Three 10μF ceramic capacitors are used in the typical
application circuit. The output capacitor should be located
near the VOUT pin as close as possible.
Thermal Considerations
For continuous operation, do not exceed absolute
maximum operation junction temperature. The maximum
power dissipation depends on the thermal resistance of
IC package, PCB layout, the rate of surroundings airflow
and temperature difference between junction to ambient.
The maximum power dissipation can be calculated by
following formula :
PD(MAX) = (TJ(MAX) − TA) / θJA
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RT9040
Where T J(MAX) is the maximum operation junction
temperature, TA is the ambient temperature and the θJA is
the junction to ambient thermal resistance.
For recommended operating conditions specification,
where TJ(MAX) is 125°C and TA is the maximum ambient
temperature. The junction to ambient thermal resistance
θJA is layout dependent. For WDFN-10L 3x3 packages,
the thermal resistance θJA is 70°C/W on the standard
JEDEC 51-7 four layers thermal test board. The maximum
power dissipation at TA = 25°C can be calculated by
following formula :
PD(MAX) = (125°C − 25°C) / (70°C/W) = 1.429W for
WDFN-10L 3x3 packages
The maximum power dissipation depends on operating
ambient temperature for fixed T J(MAX) and thermal
resistance θJA. The Figure 2 of derating curves allows the
designer to see the effect of rising ambient temperature
on the maximum power allowed.
Maximum Power Dissipation (W)
1.60
Four Layers PCB
1.40
1.20
WDFN-10L 3x3
1.00
0.80
0.60
0.40
0.20
0.00
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 2. Derating Curve of Maximum Power Dissipation
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DS9040-04 January 2014
RT9040
Outline Dimension
D2
D
L
E
E2
1
e
SEE DETAIL A
2
b
2
1
DETAIL A
Pin #1 ID and Tie Bar Mark Options
A
A1
1
A3
Note : The configuration of the Pin #1 identifier is optional,
but must be located within the zone indicated.
Dimensions In Millimeters
Dimensions In Inches
Symbol
Min
Max
Min
Max
A
0.700
0.800
0.028
0.031
A1
0.000
0.050
0.000
0.002
A3
0.175
0.250
0.007
0.010
b
0.180
0.300
0.007
0.012
D
2.950
3.050
0.116
0.120
D2
2.300
2.650
0.091
0.104
E
2.950
3.050
0.116
0.120
E2
1.500
1.750
0.059
0.069
e
L
0.500
0.350
0.020
0.450
0.014
0.018
W-Type 10L DFN 3x3 Package
Richtek Technology Corporation
14F, No. 8, Tai Yuen 1st Street, Chupei City
Hsinchu, Taiwan, R.O.C.
Tel: (8863)5526789
Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should
obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot
assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be
accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries.
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