®
RT9078
2μ
μA IQ, 300mA Low-Dropout Linear Regulator
General Description
Features
The RT9078 is a low-dropout (LDO) voltage regulators with
enable function that operates from 1.2V to 5.5V. It provides
up to 300mA of output current and offers low-power
operation in miniaturized packaging.
The features of low quiescent current as low as 2μA and
almost zero disable current is ideal for powering the battery
equipment to a longer service life. The RT9078 is stable
with the ceramic output capacitor over its wide input range
from 1.2V to 5.5V and the entire range of output load
current (0mA to 300mA).
Pin Configuration
(TOP VIEW)
VOUT
SNS/NC
5
4
2
3
Applications
VIN GND EN
TSOT-23-5
VOUT
2μ
μA Ground Current at no Load
PSRR = 75dB at 1kHz
Adjustable Output Voltage Available by Specific
Application
±2% Output Accuracy
300mA (VIN ≥ 1.7V) Output Current with EN
Low (0.1μ
μA) Disable Current
1.2V to 5.5V Operating Input Voltage
Dropout Voltage : 0.15V at 300mA when VOUT ≥ 3V
Support Fixed Output Voltage 0.8V, 1.0V, 1.05V, 1.1V,
1.2V, 1.25V, 1.3V, 1.5V, 1.8V, 1.85V, 2.5V, 2.8V, 2.85V,
3V, 3.1V, 3.3V, 3.45V
Stable with Ceramic or Tantalum Capacitor
Current Limit Protection
Over Temperature Protection
TSOT-23-5 and ZQFN-4L 1x1 (ZDFN-4L 1x1) Packages
Available
1
4
VIN
3
EN
Portable, Battery Powered Equipment
Ultra Low Power Microcontrollers
Notebook Computers
SGND
GND
2
5
ZQFN-4L 1x1 (ZDFN-4L 1x1)
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November 2017
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RT9078
Ordering Information
Marking Information
RT9078/NPin 1 Orientation***
(2) : Quadrant 2, Follow EIA-481-D
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Package Type
J5 : TSOT-23-5
QZ : ZQFN-4L 1x1 (Z-Type)
(ZDFN-4L 1x1)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Output Voltage
08 : 0.8V
:
33 : 3.3V
1B : 1.25V
1H : 1.85V
2H : 2.85V
1K : 1.05V
3D : 3.45V (ZQFN-4L 1x1 only)
Special Request : Any voltage between
0.8V and 3.3V under specific business
agreement
Pin Function
RT9078 : Without SNS Pin
RT9078N : With SNS Pin**
Note :
***Empty means Pin1 orientation is Quadrant 1
Richtek products are :
**Available for output target adjustment (Ex : RT9078N-08GJ5
with 0.8V reference level for output target adjustment)
RoHS compliant and compatible with the current require-
Suitable for use in SnPb or Pb-free soldering processes.
ments of IPC/JEDEC J-STD-020.
Functional Pin Description
Pin No.
TSOT-23-5 ZQFN-4L 1x1 (ZDFN-4L 1x1)
Pin Name
Pin Function
1
4
VIN
Supply voltage input.
2
2
GND
Ground.
3
3
EN
Enable control input.
4
--
SNS
Output voltage sense. (RT9078N only)
NC
No internal connection.
5
1
VOUT
Output of the regulator.
--
5 (Exposed Pad)
SGND
Substrate of chip. Leave floating or tie to GND.
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DS9078-10
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RT9078
Functional Block Diagram
VIN
(without sense
function)
Current/Thermal
Sense
GND
SNS
(with sense
function)
+
-
EN
Bandgap
Reference
VOUT
R1
EN
R2
Operation
Basic operation
Current Limit Protection
The RT9078 is a low quiescent current linear regulator
designed especially for low external components system.
The input voltage range is from 1.2V to 5.5V.
The RT9078 provides current limit function to prevent the
device from damages during over-load or shorted-circuit
condition. This current is detected by an internal sensing
transistor.
The minimum required output capacitance for stable
operation is 1μF capacitance after consideration of the
temperature and voltage coefficient of the capacitor.
Output Transistor
The RT9078 builds in a P-MOSFET output transistor which
provides a low switch-on resistance for low dropout voltage
applications.
Over Temperature Protection
The over temperature protection function will turn off the
P-MOSFET when the junction temperature exceeds 150°C
(typ.), and the output current exceeds 80mA. Once the
junction temperature cools down by approximately 20°C,
the regulator will automatically resume operation.
Error Amplifier
The Error Amplifier compares the internal reference voltage
with the output feedback voltage from the internal divider,
and controls the Gate voltage of P-MOSFET to support
good line regulation and load regulation at output voltage.
Enable
The RT9078 delivers the output power when it is set to
enable state. When it works in disable state, there is no
output power and the operation quiescent current is almost
zero.
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RT9078
Absolute Maximum Ratings
(Note 1)
VIN, VOUT, SNS, EN to GND ------------------------------------------------------------------------------------------VOUT to VIN ---------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
TSOT-23-5 ------------------------------------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1) -------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2)
TSOT-23-5, θJA ------------------------------------------------------------------------------------------------------------TSOT-23-5, θJC ------------------------------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1), θJA -------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1), θJC ------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3)
HBM (Human Body Model) ----------------------------------------------------------------------------------------------
Recommended Operating Conditions
−0.3V to 6.5V
−6.5V to 0.3V
0.43W
0.44W
230.6°C/W
21.8°C/W
226°C/W
43°C/W
260°C
150°C
−65°C to 150°C
2kV
(Note 4)
Input Voltage, VIN --------------------------------------------------------------------------------------------------------- 1.2V to 5.5V
Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VOUT + 1 < VIN < 5.5V, TA = 25°C, unless otherwise specified)
Parameter
Min
Typ
Max
Unit
0.8
--
3.3
V
ILOAD = 1mA
2
--
2
%
0.8V VOUT 1.05V
--
0.7
0.97
1.05V VOUT 1.2V
--
0.5
0.92
1.2V VOUT 1.5V
--
0.4
0.57
1.5V VOUT 1.8V
--
0.3
0.47
1.8V VOUT 2.1V
--
0.24
0.33
2.1V VOUT 2.5V
--
0.21
0.3
2.5V VOUT 2.8V
--
0.18
0.25
2.8V VOUT 3V
--
0.16
0.23
3V VOUT
--
0.15
0.2
ILOAD = 0mA, VOUT 5.5V
VIN VOUT + VDROP
--
2
4
A
Shutdown GND Current
(Note 6)
VEN = 0V
--
0.1
0.5
A
Shutdown Leakage Current
(Note 6)
VEN = 0V, VOUT = 0V
--
0.1
0.5
A
Fixed Output Voltage Range
Symbol
VOUT
DC Output Accuracy
Dropout Voltage
(ILOAD = 300mA)
(Note 5)
VCC Consumption Current
Test Conditions
VDROP
IQ
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V
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DS9078-10
November 2017
RT9078
Parameter
EN Input Current
Symbol
IEN
LINE
Line Regulation
Test Conditions
Min
Typ
Max
Unit
--
--
0.1
A
1.2V VIN 1.5V
--
0.3
0.6
1.5V VIN 1.8V
--
0.15
0.3
1.8V VIN 5.5V
--
0.13
0.35
VEN = 5.5V
ILOAD = 1mA
%
Load Regulation
LOAD
1mA < ILOAD < 300mA
--
0.5
1
%
Power Supply Rejection
Ratio
PSRR
VIN = 3V, ILOAD = 50mA,
COUT = 1F, VOUT = 2.5V, f = 1kHz
--
75
--
dB
VOUT = 0.8V
--
38
--
VOUT = 1.2V
--
46
--
VOUT = 1.8V
--
48
--
VOUT = 3.3V
--
51
--
COUT = 1F,
ILOAD = 150mA,
BW = 10Hz to
100kHz,
VIN = VOUT + 1V
Output Voltage Noise
Output Current Limit
VRMS
ILIM
VOUT = 90%VOUT(Normal)
350
600
--
Logic-High
VIH
VIN = 5V
0.9
--
--
Logic-Low
VIL
VIN = 5V
--
--
0.4
Thermal Shutdown
Temperature
TSD
ILOAD = 30mA, VIN 1.5V
--
150
--
C
Thermal Shutdown
Hysteresis
TSD
--
20
--
C
--
80
--
Enable Input
Voltage
Discharge Resistance
EN = 0V, VOUT = 0.1V
mA
V
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 in the natural convection at TA = 25°C on a two-layer Richtek Evaluation Board for ZQFN-4L 1x1 (ZDFN4L1x1) Package.
θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7 for TSOT-235 Package.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Note 5. The dropout voltage is defined as VIN − VOUT, when VOUT is 98% of the normal value of VOUT.
Note 6. The specification is tested at wafer stage and guarantee by design after assembly.
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RT9078
Typical Application Circuit
RT9078N
VIN
CIN
1µF
EN
VIN
VOUT
VOUT
COUT
(Capacitance 1µF)
SNS
EN
GND
Figure 1. Application with Sense Function
RT9078
VIN
CIN
1µF
EN
VIN
VOUT
VOUT
COUT
(Capacitance 1µF)
EN
GND
Figure 2. Application without Sense Function
RT9078N
VIN
CIN
1µF
VIN
VOUT
VOUT
R1
SNS
EN
EN
NC
COUT
(Capacitance
1µF)
R2
GND
Figure 3. Adjustable Output Voltage Application Circuit
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RT9078
Typical Operating Characteristics
Output Voltage vs. Temperature
3.40
0.88
3.38
0.86
3.36
Output Voltage (V)
Output Voltage (V)
Output Voltage vs. Temperature
0.90
0.84
0.82
0.80
VIN = 1.2V
VIN = 2.1V
VIN = 5.5V
0.78
0.76
0.74
3.34
3.32
VIN = 3.8V
VIN = 4.5V
VIN = 5.5V
3.30
3.28
3.26
3.24
0.72
3.22
VOUT = 0.8V, ILOAD = 1mA
0.70
VOUT = 3.3V, ILOAD = 1mA
3.20
-50
-25
0
25
50
75
100
125
-50
-25
Temperature (°C)
50
75
1.00
0.86
0.95
125
0.90
0.84
0.82
0.80
0.78
0.76
0.85
0.80
VIN = 3V
VIN = 5V
0.75
0.70
0.65
0.60
0.74
0.55
VOUT = 0.8V, ILOAD = 1mA
0.72
ILOAD = 0mA to 300mA
0.50
1.2
1.7
2.2
2.7
3.2
3.7
4.2
4.7
5.2
5.7
0
50
Ground Current vs. Load Current
0.35
100
150
200
250
300
Load Current (mA)
Input Voltage (V)
0.35
Ground Current vs. Load Current
0.30
GND Current (mA)
0.30
0.25
0.20
0.15
TA = 85°C
TA = 25°C
TA = −40°C
0.10
0.05
0.25
0.20
TA = −40°C
TA = 25°C
TA = 125°C
0.15
0.10
0.05
VOUT = 3V
VOUT = 0.8V
0.00
0.001
0.01
0.1
1
10
100
Load Current (mA)
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100
Output Voltage vs. Load Current
0.88
Output Voltage (V)
Output Voltage (V)
25
Temperature (°C)
Output Voltage vs. Input Voltage
GND Current (mA)
0
November 2017
1000
0.00
0.001
0.01
0.1
1
10
100
1000
Load Current (mA)
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RT9078
Shutdown Leakage Current vs. Temperature
Shutdown Current vs. Input Voltage
0.10
VOUT = 0.8V, EN = 0V
Shutdown Leakage Current (μA)1
Shutdown Current (μA)1
0.1
0.08
0.06
0.04
0.02
0
VOUT = 0.8V, EN = 0V
0.08
0.06
0.04
VIN = 1.8V
VIN = 5.5V
0.02
0.00
1
2
3
4
5
6
-50
-25
0
Input Voltage (V)
EN Threshold vs. Input Voltage
Enable High
125
Enable High
0.6
Enable Low
EN Threshold (V)
EN Threshold (V)
100
0.67
0.5
0.4
0.3
0.2
0.66
0.65
0.64
0.62
0
0.61
2
3
4
5
Enable Low
0.63
0.1
1
VIN = 5.5V
-50
6
-25
0
Input Voltage (V)
ILOAD = 300mA
Current Limit (mA)
0.16
ILOAD = 200mA
0.12
0.10
0.08
ILOAD = 100mA
0.06
0.04
100
125
VOUT = 0.8V
VOUT = 3.3V
500
400
300
200
100
ILOAD = 10mA
0.02
75
600
0.18
0.14
50
Current Limit vs. Temperature
700
VOUT = 2.85V
25
Temperature (°C)
Dropout Voltage vs. Temperature
Dropout Voltage (V)
75
EN Threshold vs. Temperature
0.7
0.20
50
0.68
0.8
0.22
25
Temperature (°C)
VIN = 5V
0.00
0
-50
-25
0
25
50
75
100
Temperature (°C)
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125
-50
-25
0
25
50
75
100
125
Temperature (°C )
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RT9078
Fold-Back Current Limit vs. Temperature
SNS Input Current vs. Temperature
350
0.9
0.8
SNS Input Current (μA)
Fold-Back Current Limit (mA)
VOUT = 0.8V
300
250
VOUT = 3.3V
200
150
100
50
VIN = 5V
0
0.7
0.6
0.5
0.4
0.3
0.2
0.1
VIN = 5V, VOUT = 0.8V, EN = H
0.0
-50
-25
0
25
50
75
100
125
-50
25
50
75
Temperature (°C)
Power On from EN
Power Off from EN
EN
(2V/Div)
VOUT
(2V/Div)
VOUT
(2V/Div)
VIN = 3.8V, VOUT = 2.8V, ILOAD = 300mA
I LOAD
(200mA/Div)
100
125
VIN = 3.8V, VOUT = 2.8V, ILOAD = 300mA
Time (250μs/Div)
Time (500μs/Div)
Line Transient
Load Transient
VIN = 3.8V, VOUT = 1.8V, ILOAD = 1mA to 300mA
VIN = 2.8V to 3.8V, VOUT = 1.8V, ILOAD = 1mA
I LOAD
(1A/Div)
VIN
(1V/Div)
VOUT
(10mV/Div)
VOUT
(2mV/Div)
Time (250μs/Div)
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0
Temperature (°C )
EN
(2V/Div)
I LOAD
(200mA/Div)
-25
November 2017
Time (100μs/Div)
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RT9078
PSRR vs. Frequency
0
-20
-20
ILOAD = 50mA
ILOAD = 30mA
ILOAD = 15mA
ILOAD = 10mA
-40
PSRR (dB)
PSRR (dB)
PSRR vs. Frequency
0
-60
-80
-40
ILOAD = 150mA
ILOAD = 50mA
ILOAD = 15mA
-60
-80
VIN = 2.8V, VOUT = 0.8V, COUT = 1μF
VIN = 3.3V, VOUT = 2.8V, COUT = 1μF
-100
-100
10
100
1000
10000
100000
1000000
10
100
1000
100000
1000000
Frequency (Hz)
Frequency (Hz)
Output Noise
Output Noise
500
500
400
400
300
300
200
200
Noise (μV)
Noise (μV)
10000
100
0
-100
-200
100
0
-100
-200
-300
-300
VIN = 2.5V, VOUT = 0.8V, ILOAD = 300mA,
COUT = 1μF, Frequency = 10Hz to 100kHz
-400
-500
VIN = 4.5V, VOUT = 3.3V, ILOAD = 300mA,
COUT = 1μF, Frequency = 10Hz to 100kHz
-400
-500
0
1
2
3
4
5
6
7
8
Sec (m)
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9
10
0
1
2
3
4
5
6
7
8
9
10
Sec (m)
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RT9078
Application Information
Enable
The RT9078 has an EN pin to turn on or turn off the
regulator, When the EN pin is in logic high, the regulator
will be turned on. The shutdown current is almost 0μA
typical. The EN pin may be directly tied to VIN to keep the
part on. The Enable input is CMOS logic and cannot be
left floating.
Adjustable Output Voltage Setting
Because of the small input current at the SNS pin, the
RT9078N with SNS pin also can work as an adjustable
output voltage LDO. Figure 3 gives the connections for
the adjustable output voltage application. The resistor
divider from VOUT to SNS sets the output voltage when
in regulation.
The voltage on the SNS pin sets the output voltage and is
determined by the values of R1 and R2. In order to keep
a good temperature coefficient of output voltage, the values
of R1 and R2 should be selected carefully to ignore the
temperature coefficient of input current at the SNS pin. A
current greater than 50μA in the resistor divider is
recommended to meet the above requirement. The
adjustable output voltage can be calculated using the
formula given in equation 1 :
VOUT R1 + R2 VSNS
(1)
R2
where VSNS is determined by the output voltage selections
in the ordering information of RT9078N. The maximum
adjustable output voltage can be as high as input voltage
deducted by the dropout voltage.
When we choose 51kΩ and 16kΩ as R1 and R2
respectively, and select a 0.8V output at SNS pin, the
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DS9078-10
November 2017
adjustable output voltage will be set to around 3.35V. Its
temperature coefficient in Figure 4 is still perfect in such
kind of application.
Output Voltage vs. Temperature
3.35
3.34
Output Voltage (V)
Like any low dropout linear regulator, the RT9078’s
external input and output capacitors must be properly
selected for stability and performance. Use a 1μF or larger
input capacitor and place it close to the IC's VIN and GND
pins. Any output capacitor meeting the minimum 1mΩ
ESR (Equivalent Series Resistance) and capacitance larger
than 1μF requirement may be used. Place the output
capacitor close to the IC's VOUT and GND pins. Increasing
capacitance and decreasing ESR can improve the circuit's
PSRR and line transient response.
3.33
3.32
3.31
3.30
3.29
ILOAD = 1mA
3.28
-50
-25
0
25
50
75
100
125
Temperature (°C)
Figure 4. Temperature Coefficient of Adjustable Output
Voltage
The minimum recommended 50μA in the resistor divider
makes the application no longer an ultra low quiescent
LDO. Figure 5 is another fine adjustable output voltage
application can keep the LDO still operating in low power
consumption. The fine tune range is recommended to be
less than 50mV (R1 ≤ 91kΩ) in order to keep a good
temperature coefficient of the output voltage.
RT9078N
VIN
VOUT
1µF
R1
SNS
56pF/NC
1µF
EN
GND
Figure 5. Fine Adjustable Output Voltage Application
Circuit
There isn't extra current consumption in the above
application. But the temperature coefficient of output
voltage will be degraded by the input current at SNS pin.
If the tuning range is larger than 50mV, a compensation
capacitor (56pF) is required to keep the stability of output
voltage. The fine adjustable output voltage is calculated
using the formula given in equation 2 :
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RT9078
(2)
where ISNS is the input Current at SNS pin (typical 550nA
at room temperature) and VSNS is determined by the
output voltage selections in the ordering information of
RT9078N.
Current Limit
The RT9078 contains an independent current limiter, which
monitors and controls the pass transistor's gate voltage,
limiting the output current to 0.6A (typ.). The current
limiting level is reduced to around 0.3A named fold-back
current limit when the output voltage is further decreased.
The output can be shorted to ground indefinitely without
damaging the part.
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curve in Figure 6 allows the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
0.6
Maximum Power Dissipation (W)1
VOUT VSNS + ISNS R1
Four-Layer PCB for TSOT-23-5 package
Two-Layer Richtek EVB for ZQFN (ZDFN)-4L 1x1
package
0.5
0.4
0.3
ZQFN-4L 1x1 (ZDFN-4L 1x1)
0.2
TSOT-23-5
0.1
0.0
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 and TA is the
ambient temperature. The junction to ambient thermal
resistance, θJA, is layout dependent. For TSOT-23-5
package, the thermal resistance, θJA, is 230.6°C/W on a
standard JEDEC 51-7 four-layer thermal test board. For
ZQFN-4L 1x1 (ZDFN-4L 1x1) package, the thermal
resistance, θJA, is 226°C/W on a two-layer Richtek
evaluation board. The maximum power dissipation at TA =
25°C can be calculated by the following formula :
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 6. Derating Curve of Maximum Power Dissipation
Layout Consideration
For best performance of the RT9078, the PCB layout
suggestions below are highly recommend. All circuit
components placed on the same side and as near to the
respective LDO pin as possible, place the ground return
path connection to the input and output capacitor. Using
vias and long power traces for the input and output
capacitors connection is discouraged and have negatively
affects on performance. Figure 7 and Figure 8 shows the
examples for the layout reference that reduce conduction
trace loop, helping inductive parasitic minimize, load
transient reduction and good circuit stability.
PD(MAX) = (125°C − 25°C) / (230.6°C/W) = 0.43W for
TSOT-23-5 package
PD(MAX) = (125°C − 25°C) / (226°C/W) = 0.44W for
ZQFN-4L 1x1 (ZDFN-4L 1x1) package
The maximum power dissipation depends on the operating
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is a registered trademark of Richtek Technology Corporation.
DS9078-10
November 2017
RT9078
Ground Power Plane
VOUT
1
4
VIN
3
EN
SGND
GND
5
2
Place input/output capacitors as close
as possible to the connecting pins for
minimize power loop area and low
impedance connection to GND plate.
Connected with
enable source by via
Figure 7. PCB Layout Guide for ZQFN-4L 1x1 package
Place input/output capacitors as close
as possible to the connecting pins for
minimize power loop area and low
impedance connection to GND plate.
Resistive divider is for
output voltage adjustment
(RT9078N package only).
R1
R2
VOUT
SNS/NC
5
4
Ground Power Plane
2
Thermal vias helps to
reduce power trace
and improve thermal
dissipation
3
VIN GND EN
Enable source
Figure 8. PCB Layout Guide for TSOT-23-5 package
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
DS9078-10
November 2017
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT9078
Outline Dimension
H
D
L
B
C
b
A
A1
e
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.700
1.000
0.028
0.039
A1
0.000
0.100
0.000
0.004
B
1.397
1.803
0.055
0.071
b
0.300
0.559
0.012
0.022
C
2.591
3.000
0.102
0.118
D
2.692
3.099
0.106
0.122
e
0.838
1.041
0.033
0.041
H
0.080
0.254
0.003
0.010
L
0.300
0.610
0.012
0.024
TSOT-23-5 Surface Mount Package
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
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14
is a registered trademark of Richtek Technology Corporation.
DS9078-10
November 2017
RT9078
1
1
2
2
DETAIL A
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.
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.300
0.400
0.012
0.016
A1
0.000
0.050
0.000
0.002
A3
0.117
0.162
0.005
0.006
b
0.175
0.275
0.007
0.011
D
0.900
1.100
0.035
0.043
D2
0.450
0.550
0.018
0.022
E
0.900
1.100
0.035
0.043
E2
0.450
0.550
0.018
0.022
e
L
0.625
0.200
0.025
0.300
0.008
0.012
H
0.039
0.002
H1
0.064
0.003
Z-Type 4L QFN 1x1 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.
DS9078-10
November 2017
www.richtek.com
15
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