RT5795A [RICHTEK]
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| 型号： | RT5795A |
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RICHTEK TECHNOLOGY CORPORATION |
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®
RT5795A
2A, 5.5V, Low IQ ACOT Synchronous Step-Down Converter
General Description
Features
2.5V to 5.5V Input Voltage Range
Advanced COT Control loop design
Fast Transient Response
The RT5795A is a full featured 5.5V, 2A, Advanced
Constant-On-Time (ACOT) synchronous step-down
converter with two integrated MOSFETs. The advanced
COT operation allows transient responses to be optimized
over a wide range of loads, and output capacitors to
efficiently reduce external component count. The RT5795A
provides up to 2.7MHz switching frequency to minimize
the size of output inductor and capacitors. The RT5795A
is available in the WDFN-8SL 2x2 package.
Internal 100mΩ and 80mΩ Synchronous Rectifier
Highly Accurate VOUT Regulation Over Load/Line
Range
Robust Loop Stability with Low-ESR COUT
Ordering Information
RT5795A
Applications
Mobile Phones and HandheldDevices
Pin 1 Orientation***
(2) : Quadrant 2, Follow EIA-481-D
Package Type
QW : WDFN-8SL 2x2 (W-Type)
(Exposed Pad-Option 2)
STB, Cable Modem, and xDSL Platforms
WLANASIC Power / Storage (SSDand HDD)
General Purpose for POL LV Buck Converter
Lead Plating System
G : Green (Halogen Free and Pb Free)
Pin Configuration
Note :
(TOP VIEW)
***Empty means Pin1 orientation is Quadrant 1
Richtek products are :
1
2
3
4
8
7
6
5
EN
PGND
AGND
FB
VIN
LX
PGOOD
VOS
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
9
WDFN-8SL 2x2
Suitable for use in SnPb or Pb-free soldering processes.
Marking Information
2L : Product Code
W : Date Code
2LW
Simplified Application Circuit
RT5795A
PGOOD
Power Good
VIN
EN
V
IN
LX
V
OUT
PGND
AGND
R1
R2
VOS
FB
Copyright 2019 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS5795A-06 November 2019
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1
RT5795A
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
EN
Enable control input. Pull High to Enable.
2,
Power ground. The exposed pad must be soldered to a large PCB and connected
to PGND for maximum power dissipation.
PGND
9 (Exposed Pad)
3
4
AGND
FB
Analog ground. Should be electrically connected to GND close to the device.
Feedback voltage input.
Output voltage sense pin for the internal control loop. Must be connected to
output.
5
6
VOS
Power good open-drain output. This pin is pulled to low if the output voltage is
below regulation limits. Can be left floating if not used.
PGOOD
Switch node. The Source of the internal high-side power MOSFET, and Drain of
the internal low-side (synchronous) rectifier MOSFET.
7
8
LX
VIN
Power input supply voltage, 2.5V to 5.5V.
Functional Block Diagram
EN
VOS
TON
AGND
VIN
UVLO
OTP
Shutdown
Control
LX
Error Amplifier
Comparator
+
-
+
+
-
FB
Logic
Control
LX
Driver
Current
Limit
LX
V
REF
Ramp
Detector
Generator
PGOOD
+
-
LX
LX
FB
AZC
PGND
V
Copyright 2019 Richtek Technology Corporation. All rights reserved.
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2
DS5795A-06 November 2019
RT5795A
Operation
Power Good
The RT5795A is a low voltage synchronous step-down
converter that can support input voltage ranging from 2.5V
to 5.5V and the output current can be up to 2A. The
RT5795A uses ACOTTM mode control. To achieve good
stability with low-ESR ceramic capacitors, theACOT uses
a virtual inductor current ramp generated inside the IC.
This internal ramp signal replaces the ESR ramp normally
provided by the output capacitor's ESR. The ramp signal
and other internal compensations are optimized for low-
ESR ceramic output capacitors.
When the output voltage is higher than PGOOD rising
threshold, the PGOOD flag is high.
Output Under-Voltage Protection (UVP)
When the output voltage is lower than 66% reference
voltage after soft-start, the UVP is triggered.
Over-Current Protection (OCP)
The RT5795A senses the current signal when the high-
side and low-side MOSFET turns on. As a result, The
OCP is a cycle-by-cycle current limit. If an over-current
condition occurs, the converter turns off the next on pulse
until inductor current drops below the OCP limit. If the
OCP is continually activated and the load current is larger
than the current provided by the converter, the output
voltage drops. Also, when the output voltage triggers the
UVP also, the current will drop to ZC and trigger the re-
soft start sequence.
In steady-state operation, the feedback voltage, with the
virtual inductor current ramp added, is compared to the
reference voltage. When the combined signal is less than
the reference, the on-time one-shot is triggered, as long
as the minimum off-time one-shot is clear and the
measured inductor current (through the synchronous
rectifier) is below the current limit. The on-time one-shot
turns on the high-side switch and the inductor current
ramps up linearly. After the on-time, the high-side switch
is turned off and the synchronous rectifier is turned on
and the inductor current ramps down linearly. At the same
time, the minimum off-time one-shot is triggered to prevent
another immediate on-time during the noisy switching
time and allow the feedback voltage and current sense
signals to settle. The minimum off-time is kept short so
that rapidly-repeated on-times can raise the inductor
current quickly when needed.
Soft-Start
An internal current source charges an internal capacitor
to build the soft-start ramp voltage. The typical soft-start
time is 150μs.
Over-Temperature Protection (OTP)
The RT5795Ahas an over-temperature protection. When
the device triggers the OTP, the device shuts down until
the temperature is back to normal.
PWM Frequency and Adaptive On-Time Control
The on-time can be roughly estimated by the equation :
VOUT
1
TON
=
where fOSC is nominal 2.7MHz
V
fOSC
IN
Under-Voltage Protection (UVLO)
The UVLO continuously monitors the VCC voltage to make
sure the device works properly. When the VCC is high
enough to reach the UVLO high threshold voltage, the
step-down converter softly starts or pre-bias to its regulated
output voltage. When the VCC decreases to its low
threshold voltage, the device shuts down.
Copyright 2019 Richtek Technology Corporation. All rights reserved.
©
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DS5795A-06 November 2019
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3
RT5795A
Absolute Maximum Ratings (Note 1)
Supply Input Voltage, VIN ----------------------------------------------------------------------------------------------- −0.3V to 6V
Switch Voltage, LX -------------------------------------------------------------------------------------------------------- −0.3V to 6V
< 50ns------------------------------------------------------------------------------------------------------------------------ −2.5V to 7V
Other Pins------------------------------------------------------------------------------------------------------------------- −0.3V to 6V
PowerDissipation, PD @ TA = 25°C
WDFN-8SL 2x2 ------------------------------------------------------------------------------------------------------------ 1.538W
Package Thermal Resistance (Note 2)
WDFN-8SL 2x2, θJA ------------------------------------------------------------------------------------------------------- 65°C/W
WDFN-8SL 2x2, θJC ------------------------------------------------------------------------------------------------------ 8°C/W
Junction Temperature ----------------------------------------------------------------------------------------------------- 150°C
Lead Temperature (Soldering, 10 sec.)------------------------------------------------------------------------------- 260°C
Storage Temperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model)---------------------------------------------------------------------------------------------- 2kV
Recommended Operating Conditions (Note 4)
Supply Input Voltage, VIN ----------------------------------------------------------------------------------------------- 2.5V to 5.5V
Junction Temperature Range-------------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range-------------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VIN = 3.6V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max Unit
Under-Voltage Lockout
Threshold
VUVLO
VCC rising
EN = 0V
2.28
2.35
2.48
--
V
Under-Voltage Lockout
Hysteresis
VUVLOHY
--
400
mV
Shutdown Supply Current
Quiescent Current
ISHDN
IQ
--
--
--
1
A
A
V
Active, VFB = 0.5V, no switching
30
--
Voltage Reference
VREF
0.441 0.45 0.459
High-Side
Current Limit
Peak current
Valley current
2.5
2
3.2
2.4
4
ILIM
A
Low-Side
2.9
VOUT falling referenced to VOUT
nominal
Power Good Threshold
Power Good Hysteresis
VPGTH
VPGHY
IPG
15
--
10
5
5
--
%
%
A
V
Hysteresis referenced to VOUT
nominal
Power Good Leakage
Current
VPG = 5V
--
0.01
--
0.1
0.3
Power Good Low Level
Voltage
VPGL
Isink = 500A
--
Enable Rising Threshold
Enable Falling Threshold
VENR
VENF
Rising
Falling
1
--
--
--
V
V
--
0.4
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4
DS5795A-06 November 2019
RT5795A
Parameter
High-Side RP-MOSFET
Low-Side RN-MOSFET
Symbol
Test Conditions
Min
--
Typ
100
80
Max
--
Unit
Switch
On-Resistance
m
--
--
Thermal Shutdown
Temperature
--
--
150
20
--
--
C
C
Thermal Shutdown
Hysteresis
Switching Frequency
fOSC
--
--
2.7
1
--
--
MHz
Output Discharge Resistor
k
Note 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 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. The copper area is 70mm2 connected with IC exposed pad.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Copyright 2019 Richtek Technology Corporation. All rights reserved.
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is a registered trademark of Richtek Technology Corporation.
DS5795A-06 November 2019
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5
RT5795A
Typical Application Circuit
RT5795A
PGOOD
6
7
8
1
Power Good
VIN
EN
V
IN
180k
10µF
L
V
LX
OUT
5
4
2, 9 (Exposed Pad)
3
R1
R2
C
OUT
VOS
FB
PGND
AGND
Table 1. Suggested Component Values
V
OUT (V)
R1 (k)
R2 (k)
39.2
L (H)
COUT (F)
1.2V
1.8V
2.5V
3.3V
65.3
117.6
178.6
248.3
0.47
22
22
22
22
39.2
1
1
1
39.2
39.2
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DS5795A-06 November 2019
RT5795A
Typical Operating Characteristics
Efficiency vs. Output Current
Efficiency vs. Output Current
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
VIN = 3.3V
VIN = 5V
VIN = 3.3V
VIN = 5V
VOUT = 1.2V, L = 0.47μH
VOUT = 1.2V, L = 0.47μH
0
0
0
0.5
1
1.5
2
0.001
0.01
0.1
1
10
10
2
Output Current (A)
Output Current (A)
Efficiency vs. Output Current
Efficiency vs. Output Current
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
VIN = 3.3V
VIN = 5V
VIN = 3.3V
VIN = 5V
VOUT = 2.5V, L = 1μH
1.5 2
VOUT = 2.5V, L = 1μH
0.001
0.01
0.1
1
0.5
1
Output Current (A)
Output Current (A)
Output Voltage vs. Output Current
Output Voltage vs. Output Current
1.250
1.240
1.230
1.220
1.210
1.200
1.190
1.180
1.170
1.160
1.150
2.60
2.58
2.56
2.54
2.52
2.50
2.48
2.46
2.44
2.42
2.40
VIN = 5V
VIN = 3.3V
VIN = 5V
VIN = 3.3V
VOUT = 1.2V, L = 0.47μH
VOUT = 2.5V, L = 1μH
0
0.5
1
1.5
0.5
1
1.5
2
Output Current (A)
Output Current (A)
Copyright 2019 Richtek Technology Corporation. All rights reserved.
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RT5795A
Output Voltage vs. Input Voltage
Output Voltage vs. Input Voltage
1.220
1.215
1.210
1.205
1.200
1.195
1.190
1.185
1.180
2.54
2.53
2.52
2.51
2.50
2.49
2.48
2.47
2.46
2.45
2.44
VOUT = 1.2V, IOUT = 0A, L = 0.47μH
3.5 4.5 5.5
VOUT = 2.5V, IOUT = 0A, L = 1μH
2.5
3
4
5
2.5
3
3.5
4
4.5
5
5.5
Input Voltage (V)
Input Voltage (V)
Switching Frequency vs. Input Voltage
Switching Frequency vs. Temperature
3.0
2.9
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
2.0
3.0
2.9
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
2.0
VOUT = 1.2V, IOUT = 0A, L = 0.47μH
VIN = 5V, VOUT = 1.2V, IOUT = 1A, L = 0.47μH
2.5
3
3.5
4
4.5
5
5.5
-50
-25
0
25
50
75
100
125
Input Voltage (V)
Temperature (°C)
Output Current Limit vs. Input Voltage
Output Current Limit vs. Temperature
4.0
3.8
3.6
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
4.0
3.8
3.6
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
VOUT = 1.2V, L = 0.47μH
VIN = 3.3V, VOUT = 1.2V, L = 0.47μH
2.5
3
3.5
4
4.5
5
5.5
-50
-25
0
25
50
75
100
125
Input Voltage (V)
Temperature (°C)
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DS5795A-06 November 2019
RT5795A
Input Voltage vs. Temperature
Output Voltage vs. Temperature
2.5
2.4
2.3
2.2
2.1
2.0
1.9
1.8
1.7
1.6
1.5
1.24
1.23
1.22
1.21
1.20
1.19
1.18
UVLO Turn On
UVLO Turn Off
VIN = 3.6V, IOUT = 0.5A
-50
-25
0
25
50
75
100
125
-50
-25
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
Enable Threshold vs. Temperature
Load Transient Response
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
VOUT
(20mV/Div)
Enable On
Enable Off
IOUT
(1A/Div)
VIN = 5V, VOUT = 2.5V, IOUT = 1A to 2A, L = 1μH
Time (50μs/Div)
-50
-25
0
25
50
75
100
125
Temperature (°C)
Load Transient Response
Load Transient Response
VOUT
(20mV/Div)
VOUT
(20mV/Div)
IOUT
(1A/Div)
IOUT
(1A/Div)
VIN = 3.3V, VOUT = 1.2V, IOUT = 1A to 2A, L = 0.47μH
Time (50μs/Div)
VIN = 5V, VOUT = 2.5V, IOUT = 0A to 2A, L = 1μH
Time (50μs/Div)
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RT5795A
Load Transient Response
Voltage Ripple
VOUT
(20mV/Div)
VOUT
(20mV/Div)
VLX
(5V/Div)
IOUT
(1A/Div)
VIN = 3.3V, VOUT = 1.2V, IOUT = 2A, L = 0.47μH
VIN = 3.3V, VOUT = 1.2V, IOUT = 0A to 2A, L = 0.47μH
Time (50μs/Div)
Time (500ns/Div)
Voltage Ripple
Voltage Ripple
VOUT
VOUT
(20mV/Div)
(20mV/Div)
VLX
VLX
(5V/Div)
(5V/Div)
VIN = 5V, VOUT = 2.5V, IOUT = 2A, L = 1μH
VIN = 3.3V, VOUT = 1.2V, IOUT = 1A, L = 0.47μH
Time (500ns/Div)
Time (500ns/Div)
Power On from VIN
Voltage Ripple
VOUT
VEN
(5V/Div)
(20mV/Div)
VOUT
(1V/Div)
VLX
(5V/Div)
VLX
(5V/Div)
IOUT
(2A/Div)
VIN = 5V, VOUT = 2.5V, IOUT = 1A, L = 1μH
VIN = 5V, VOUT = 1.2V, IOUT = 2A
Time (500ns/Div)
Time (100μs/Div)
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DS5795A-06 November 2019
RT5795A
Power Off from VIN
VEN
(5V/Div)
VOUT
(1V/Div)
VLX
(5V/Div)
IOUT
(2A/Div)
VIN = 5V, VOUT = 1.2V, IOUT = 2A
Time (100μs/Div)
Copyright 2019 Richtek Technology Corporation. All rights reserved.
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RT5795A
Application Information
The RT5795A is a single-phase step-down converter.
Advance Constant-on-Time (ACOT) with fast transient
response. An internal 0.45V reference allows the output
voltage to be precisely regulated for low output voltage
applications. A fixed switching frequency (2.7MHz)
oscillator and internal compensation are integrated to
minimize external component count. Protection features
include over current protection, under voltage protection
and over temperature protection.
will retry automatically. When the UVP condition is
removed, the converter will resume operation. The UVP
is disabled during soft-start period.
Post Short
VIN
(2V/Div)
VOUT
(500mV/Div)
Output Voltage Setting
VLX
(5V/Div)
The output voltage is set by an external resistive divider
according to the following equation :
IOUT
(2A/Div)
R1
VIN = 5V, VOUT = 1.2V, L = 1μH
VOUT VREF x (1
)
R2
where VREF equals to 0.45V typical. The resistive divider
allows the FB pin to sense a fraction of the output voltage
as shown in Figure 1.
Time (1ms/Div)
CIN and COUT Selection
V
The input capacitance, CIN, is needed to filter the
trapezoidal current at the source of the top MOSFET. To
prevent large ripple voltage, a low ESR input capacitor
sized for the maximum RMS current should be used. RMS
current is given by :
OUT
R1
FB
RT5795A
R2
GND
VOUT
V
IN
IRMS IOUT(MAX)
1
V
VOUT
Figure 1. Setting the Output Voltage
Low Supply Operation
IN
This formula has a maximum at VIN = 2VOUT, where IRMS
=
IOUT / 2. This simple worst case condition is commonly
used for design because even significant deviations do
not result in much difference. Choose a capacitor rated at
a higher temperature than required.
The RT5795A is designed to operate down to an input
supply voltage of 2.5V. One important consideration at
low input supply voltages is that the RDS(ON) of the P-
Channel and N-Channel power switches increases. The
user should calculate the power dissipation when the
RT5795A is used at 100% duty cycle with low input
voltages to ensure that thermal limits are not exceeded.
Several capacitors may also be paralleled to meet size or
height requirements in the design.
The selection of COUT is determined by the effective series
resistance (ESR) that is required to minimize voltage ripple
and load step transients, as well as the amount of bulk
capacitance that is necessary to ensure that the control
loop is stable. Loop stability can be checked by viewing
the load transient response. The output ripple, ΔVOUT, is
determined by :
Under Voltage Protection (UVP)
Hiccup Mode
For the RT5795A, it provides Hiccup Mode Under Voltage
Protection (UVP). When the output voltage is lower than
66% reference voltage after soft-start, the UVP is triggered.
If the UVP condition remains for a period, the RT5795A
1
VOUT I ESR
L
8fCOUT
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DS5795A-06 November 2019
RT5795A
The output ripple is highest at maximum input voltage
since ΔIL increases with input voltage. Multiple capacitors
placed in parallel may be needed to meet the ESR and
RMS current handling requirements.Dry tantalum, special
polymer, aluminum electrolytic and ceramic capacitors are
all available in surface mount packages. Special polymer
capacitors offer very low ESR, but have lower capacitance
density than other types. Tantalum capacitors have the
highest capacitance density, but it is important to only
use types that have been surge tested for use in switching
power supplies. Aluminum electrolytic capacitors have
significantly higher ESR, but can be used in cost-sensitive
applications provided that consideration is given to ripple
current ratings and long term reliability. Ceramic capacitors
have excellent low ESR characteristics, but can have a
high voltage coefficient and audible piezoelectric effects.
Thermal Considerations
For continuous operation, do not exceed absolute
maximum junction temperature. The maximum power
dissipation depends on the thermal resistance of the IC
package, PCB layout, rate of surrounding airflow, and
difference between junction and ambient temperature. The
maximum power dissipation can be calculated by the
following formula :
PD(MAX) = (TJ(MAX) − TA) / θJA
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
For recommended operating condition specifications, the
maximum junction temperature is 125°C. The junction to
ambient thermal resistance, θJA, is layout dependent. The
junction to ambient thermal resistance, θJA, is layout
dependent. For WDFN-8SL 2x2 packages, the thermal
resistance, θJA, is 65°C/W on a standard JEDEC 51-7
four-layer thermal test board. The maximum power
dissipation at TA = 25°C can be calculated by the following
formula :
The high Q of ceramic capacitors with trace inductance
can also lead to significant ringing.
Using Ceramic Input and Output Capacitors
Higher value, lower cost ceramic capacitors are now
becoming available in smaller case sizes. Their high ripple
current, high voltage rating and low ESR make them ideal
PD(MAX) = (125°C − 25°C) / (65°C/W) = 1.538W for
WDFN-8SL 2x2 package
for switching regulator applications. However, care must
be taken when these capacitors are used at the input and
output. When a ceramic capacitor is used at the input
and the power is supplied by a wall adapter through long
wires, a load step at the output can induce ringing at the
input, VIN. At best, this ringing can couple to the output
and be mistaken as loop instability. At worst, a sudden
inrush of current through the long wires can potentially
cause a voltage spike at VIN large enough to damage the
part.
The maximum power dissipation depends on the operating
ambient temperature for fixed TJ(MAX) and thermal
resistance, θJA. The derating curve in Figure 2 allows the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
2.0
Four-Layer PCB
1.6
1.2
0.8
0.4
0.0
Table 2. Capacitors for CIN and COUT
Component
Supplier
CapacitanceCase
Part No.
(F)
10F
22F
Size
1206
1206
MuRata GRM31CR71A106KA01
MuRata GRM31CR71A226KA01
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 2. Derating Curve of Maximum PowerDissipation
Copyright 2019 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS5795A-06 November 2019
www.richtek.com
13
RT5795A
Layout Considerations
Flood all unused areas on all layers with copper. Flooding
with copper will reduce the temperature rise of power
components. Connect the copper areas to any DC net
(VIN, VOUT, GND, or any other DC rail in the system).
Follow the PCB layout guidelines for optimal performance
of the RT5795A.
Connect the terminal of the input capacitor(s), CIN, as
close as possible to the VINpin. This capacitor provides
the AC current into the internal power MOSFETs.
Connect the FB pin directly to the feedback resistors.
The resistive voltage divider must be connected between
VOUT andGND.
LX node experiences high frequency voltage swing and
should be kept within a small area. Keep all sensitive
small-signal nodes away from the LX node to prevent
stray capacitive noise pick up.
Input capacitor must be placed
as close to the IC as possible.
C
C
IN
V
IN
GND
LX should be connected to inductor by
wide and short trace. Keep sensitive
components away from this trace
IN
1
2
3
4
8
7
6
5
EN
PGND
AGND
FB
VIN
LX
PGOOD
VOS
9
R2
L
C
OUT
OUT
R1
C
V
V
OUT
OUT
The feedback and must be connected as close to the
device as possible. Keep sensitive component away.
Figure 3. PCB Layout Guide
Copyright 2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
©
www.richtek.com
14
DS5795A-06 November 2019
RT5795A
Outline Dimension
2
1
2
1
DETAILA
Pin #1 ID and Tie Bar Mark Options
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.
0.700
0.000
0.175
0.200
1.900
1.150
1.550
1.900
0.750
0.850
Max.
0.800
0.050
0.250
0.300
2.100
1.250
1.650
2.100
0.850
0.950
Min.
0.028
0.000
0.007
0.008
0.075
0.045
0.061
0.075
0.030
0.033
Max.
0.031
0.002
0.010
0.012
0.083
0.049
0.065
0.083
0.033
0.037
A
A1
A3
b
D
Option1
D2
E2
Option2
E
Option1
Option2
e
L
0.500
0.020
0.250
0.350
0.010
0.014
W-Type 8SL DFN 2x2 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. 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.
DS5795A-06 November 2019
www.richtek.com
15
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