2024年3月12日发(作者：单尘)
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Application Note: SY8121
High Efficiency Fast Response, 2A, 18V Input
1MHz Synchronous Step Down Regulator
General Description Features
SY8121 develops high efficiency synchronous step-
down DC-DC converter capable of delivering 2A load
•
Low R
DS(ON)
for internal switches
(top/bottom):140/130 m
Ω
current . SY8121 operates over a wide input voltage
range from 4.5V to 18V and integrates main switch and
•
4.5-18V input voltage range
synchronous switch with very low R
•
2A load current capability
DS(ON)
to minimize
the conduction loss.
•
Instant PWM architecture to achieve fast transient
responses
SY8121 adopts the instant PWM architecture to
•
Internal softstart limits the inrush current
achieve fast transient responses for high step down
•
2% 0.6V reference
applications and high efficiency at light loads. In
•
RoHS Compliant and Halogen Free
addition, it operates at pseudo-constant frequency of 1
•
Compact package: SOT23-6/ DFN2x2-6
MHz under heavy load conditions to minimize the size
of inductor and capacitor.
Ordering Information
Applications
SY8121
□
(
□□
)
□
•
Set Top Box
Temperature Code
•
Portable TV
Package Code
•
Access Point Router
Optional Spec Code
•
DSL Modem
Temperature Range:
-
40°C to 85°C
•
LCD TV
Typical Applications
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 1
S
AN_SY8121
Pinout
(
top view)
BS
GND
FB
EN
IN
LX
1
2
3
4
5
6
6
5
4
3
2
1
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Supply Input Voltage -------------------------------------------------------------------------------------------------------- 21V
LX, EN Voltage------------------------------------------------------------------------------------------------------- V
IN
+ 0.3V
FB, BS-LX Voltage------------------------------------------------------------------------------------------------------------- 4V
Power Dissipation, P
D
@ T
A
= 25°C SOT23-6, ------------------------------------------------------------------------- 0.6W
Package Thermal Resistance (Note 2)
θ
JA
------------------------------------------------------------------------------------------------------------- 170°C/W
θ
JC
--------------------------------------------------------------------------------------------------------------- 75°C/W
Junction Temperature Range --------------------------------------------------------------------------------------------- 150°C
Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------------- 260°C
Storage Temperature Range -----------------------------------------------------------------------------------
-
65°C to 150°C
Recommended Operating Conditions
(Note 3)
Supply Input Voltage --------------------------------------------------------------------------------------------- 4.5V to 18V
Junction Temperature Range --------------------------------------------------------------------------------- -40°C to 125°C
Ambient Temperature Range ----------------------------------------------------------------------------------
-
40°C to 85°C
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 2
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Absolute Maximum Ratings
(Note 1)
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Pin Name SOT23-6 DFN2x2-6 Pin Description
Boot-Strap Pin. Supply high side gate driver. Decouple this pin to LX pin
with 0.1uF ceramic cap.
Ground pin
Output Feedback Pin. Connect this pin to the center point of the output
resistor divider (as shown in Figure 1) to program the output voltage:
V
OUT
=0.6*(1+R1/R2)
Enable control. Pull high to turn on. Do not float.
Input pin. Decouple this pin to GND pin with at least 1uF ceramic cap
Inductor pin. Connect this pin to the switching node of inductor
a
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Top Mark:
JWxyz for SY8121ABC
,
(Device code: JW, x=year code, y=week code, z= lot number code)
PTxyz for SY8121DEC
,
(Device code: PT, x=year code, y=week code, z= lot number code)
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(SOT23-6) (DFN2x2-6)
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AN_SY8121
Block Diagram
IN
BS
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1.5V
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PWM
Control &
Protect
Logic
Internal
Power
Input
UVLO
4.5V
FB
0.6V
Internal
SST
Thermal
Protection
r
G
EN
Current Sense
a
i
n
LX
-
P
r
GND
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 3
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AN_SY8121
Electrical Characteristics
(
V
IN
= 12V,
V
OUT
= 1.2V,
L
= 2.2uH,
C
OUT
= 10uF,
T
A
= 25°C,
I
OUT
= 1A unless otherwise specified)
y
C
Parameter Symbol Test Conditions Min Typ Max Unit
Input Voltage Range V
IN
4.5 18 V
Quiescent Current I
Q
I
OUT
=0,
V
FB
=V
REF
×105% 400 µA
Shutdown Current I
SHDN
EN=0 5 10 µA
Feedback Reference 0.612 V 0.588 0.6
V
REF
Voltage
FB Input Current I
FB
V
FB
=V
IN
-50 50 nA
Top FET RON 0.14 Ω
R
DS(ON)1
Bottom FET RON R
DS(ON)2
0.13 Ω
Bottom FET Valley
I
LIM
2 A
Current Limit
EN Rising Threshold V
ENH
1.5 V
EN Falling Threshold V
ENL
0.4 V
Input UVLO Threshold V
UVLO
4.5 V
On Time T
ON
V
IN
= 12V
,V
OUT
=1.2V,
I
OUT
= 1A
100 ns
Min ON Time 50 ns
Min Off Time 100 ns
Thermal Shutdown Shutdown Temperature(Note4) 150
T
SDN
°C
Threshold
Hysteresis(Note4) 15
Note 1: Stresses beyond “Absolute Maximum Ratings” may cause permanent damage to the device. These are for
stress ratings. 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:
θ
JA is measured in the natural convection at T
A
= 25°C on a low effective single layer thermal conductivity
test board of JEDEC 51-3 thermal measurement standard. Pin 2 of SOT23-6 packages is the case position for
θ
JC
measurement.
Note 3: The device is not guaranteed to function outside its operating conditions.
Note4: Specified by design (not production tested)
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 4
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AN_SY8121
Typical Performance Characteristics
Efficiency vs. Load Current
100
95
)
%
90
(
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85
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80
7V
IN
,5V
OUT
12V
IN
,5V
OUT
75
16V
IN
,5V
OUT
70
00.511.52
Load Current (A)
)
%
(
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 5
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AN_SY8121
Startup
(V
IN
=12V, V
OUT
=3.3V, I
LOAD
=2A)
Shutdown
(V
IN
=12V, V
OUT
=3.3V, I
LOAD
=2A)
EN 5V/div
EN 5V/div
V
LX
10V/div
V
LX
10V/div
Time (200µs/div)
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Time (200µs/div)
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L
2A/div
c
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V
OUT
2V/divV
OUT
2V/div
I
L
2A/div
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 6
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AN_SY8121
Operation
SY8121 is a synchronous buck regulator IC that integrates
the PWM control, top and bottom switches on the same die to
minimize the switching transition loss and conduction loss.
With ultra low Rds(on) power switches and proprietary PWM
control, this regulator IC can achieve the highest efficiency
and the highest switch frequency simultaneously to minimize
the external inductor and capacitor size, and thus achieving
the minimum solution footprint.
C
Because of the high integration in the SY8121 IC, the
application circuit based on this regulator IC is rather
simple. Only input capacitor C
IN
, output capacitor C
OUT
,
output inductor L and feedback resistors (R
1
and R
2
)
need to be selected for the targeted applications
specifications.
Feedback resistor dividers R
1
and R
2
:
Choose R
1
and R
2
to program the proper output voltage.
To minimize the power consumption under light loads,
it is desirable to choose large resistance values for both
R
1
and R
2
. A value of between 10kΩ and 1MΩ is
highly recommended for both resistors. If Vout is 3.3V,
R
1
=100k is chosen, then using following equation, R
2
can be calculated to be 22.1k:
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R
2
=
0.6V
R
1
.
V
OUT
−0.6V
0.6V
FB
R
2
GND
Input capacitor C
IN
:
The ripple current through input capacitor is calculated
as：
I
CIN_RMS
=I
OUT
⋅D(1−D)
.
To minimize the potential noise problem, place a
typical X5R or better grade ceramic capacitor really
close to the IN and GND pins. Care should be taken to
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 7
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V
OUT
R
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Applications Information
r
G
SY8121 provides protection functions such as cycle by
cycle current limiting and thermal shutdown protection.
SY8121 will sense the output voltage conditions for the
fault protection.
minimize the loop area formed by C
IN
, and IN/GND
pins.
In this case, a 4.7uF low ESR ceramic capacitor is
recommended.
Output capacitor C
OUT
:
The output capacitor is selected to handle the output
ripple noise requirements. Both steady state ripple and
transient requirements must be taken into consideration
when selecting this capacitor. For the best performance,
it is recommended to use X5R or better grade ceramic
capacitor greater than 22uF capacitance.
Output inductor L:
There are several considerations in choosing this
inductor.
1) Choose the inductance to provide the desired
ripple current. It is suggested to choose the ripple
current to be about 40% of the maximum output
current. The inductance is calculated as:
V(1−V
OUT
/V
IN,MAX
)
L=
OUT
F
SW
×I
OUT,MAX
×40%
where Fsw is the switching frequency and I
OUT,MAX
is
the maximum load current.
The SY8121 regulator IC is quite tolerant of different
ripple current amplitude. Consequently, the final choice
of inductance can be slightly off the calculation value
without significantly impacting the performance.
2) The saturation current rating of the inductor must
be selected to be greater than the peak inductor
current under full load conditions.
V
OUT
(1-V
OUT
/V
IN
,
MAX
)
I
SAT
,
MIN
>I
OUT
,
MAX
+
2⋅F
SW
⋅L
3) The DCR of the inductor and the core loss at the
switching frequency must be low enough to
achieve the desired efficiency requirement. It is
desirable to choose an inductor with DCR<50mΩ
to achieve a good overall efficiency.
External Boostrap Cap
This capacitor provides the gate driver voltage for
internal high side MOSEFET. A 100nF low ESR
ceramic capacitor connected between BS pin and LX
pin is recommended.
BS
CB
100nF
LX
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AN_SY8121
Load Transient Considerations:
The SY8121 regulator IC integrates the compensation
components to achieve good stability and fast transient
responses. In some applications, adding a 22pF ceramic
cap in parallel with R1 may further speed up the load
transient responses and is thus recommended for
applications with large load transient step requirements.
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 8
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AN_SY8121
SOT23-6L Package Outline & PCB layout
1.90
2.80 -3.10
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Top View
0.95 TYP
0
.
0
1
-
0
.
1
1.90 TYP
2
.
4
0
c
e
1
.
0
0
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0
.
2
5
R
E
F
t
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0
.
1
-
0
.
1
5
-
P
r
Recommended Pad Layout
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Notes:
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p
.
0.3 -0.6
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p
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e
0.95
0.60
2
.
7
0
-
3
.
0
0
1
.
5
0
-
1
.
7
0
0.30 -0.50
1.0 -1.3
All dimension in MM
All dimension don’t not include mold flash & metal burr
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 9
AN_SY8121
DFN2x2-6 Package outline
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Top View Side View
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Bottom View Recommended PCB layout
Notes: All dimensions are in millimeters.
All dimensions don’t include mold flash & metal burr.
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 10
AN_SY8121
Taping & Reel Specification
1. SOT23-6 taping orientation
7
.
7
/
8
.
3
3.9/4.1
1.45/1.55
r
G
a
i
n
pitch(mm)
4
4
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P
r
Reel size
(Inch)
7"
7"
c
e
Package
types
Feeding direction
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2. Carrier Tape & Reel specification for packages
Reel
Width
Reel
Size
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Tape width
(mm)
8
8
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p
a
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Reel
width(mm)
8.4
8.4
d
f
o
Trailer
length(mm)
280
400
Leader length Qty per
(mm) reel
160
160
3000
3000
SOT23-6
DFN2x2
3. Others: NA
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 11
2024年3月12日发(作者：单尘)
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Application Note: SY8121
High Efficiency Fast Response, 2A, 18V Input
1MHz Synchronous Step Down Regulator
General Description Features
SY8121 develops high efficiency synchronous step-
down DC-DC converter capable of delivering 2A load
•
Low R
DS(ON)
for internal switches
(top/bottom):140/130 m
Ω
current . SY8121 operates over a wide input voltage
range from 4.5V to 18V and integrates main switch and
•
4.5-18V input voltage range
synchronous switch with very low R
•
2A load current capability
DS(ON)
to minimize
the conduction loss.
•
Instant PWM architecture to achieve fast transient
responses
SY8121 adopts the instant PWM architecture to
•
Internal softstart limits the inrush current
achieve fast transient responses for high step down
•
2% 0.6V reference
applications and high efficiency at light loads. In
•
RoHS Compliant and Halogen Free
addition, it operates at pseudo-constant frequency of 1
•
Compact package: SOT23-6/ DFN2x2-6
MHz under heavy load conditions to minimize the size
of inductor and capacitor.
Ordering Information
Applications
SY8121
□
(
□□
)
□
•
Set Top Box
Temperature Code
•
Portable TV
Package Code
•
Access Point Router
Optional Spec Code
•
DSL Modem
Temperature Range:
-
40°C to 85°C
•
LCD TV
Typical Applications
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 1
S
AN_SY8121
Pinout
(
top view)
BS
GND
FB
EN
IN
LX
1
2
3
4
5
6
6
5
4
3
2
1
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Supply Input Voltage -------------------------------------------------------------------------------------------------------- 21V
LX, EN Voltage------------------------------------------------------------------------------------------------------- V
IN
+ 0.3V
FB, BS-LX Voltage------------------------------------------------------------------------------------------------------------- 4V
Power Dissipation, P
D
@ T
A
= 25°C SOT23-6, ------------------------------------------------------------------------- 0.6W
Package Thermal Resistance (Note 2)
θ
JA
------------------------------------------------------------------------------------------------------------- 170°C/W
θ
JC
--------------------------------------------------------------------------------------------------------------- 75°C/W
Junction Temperature Range --------------------------------------------------------------------------------------------- 150°C
Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------------- 260°C
Storage Temperature Range -----------------------------------------------------------------------------------
-
65°C to 150°C
Recommended Operating Conditions
(Note 3)
Supply Input Voltage --------------------------------------------------------------------------------------------- 4.5V to 18V
Junction Temperature Range --------------------------------------------------------------------------------- -40°C to 125°C
Ambient Temperature Range ----------------------------------------------------------------------------------
-
40°C to 85°C
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 2
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Absolute Maximum Ratings
(Note 1)
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Pin Name SOT23-6 DFN2x2-6 Pin Description
Boot-Strap Pin. Supply high side gate driver. Decouple this pin to LX pin
with 0.1uF ceramic cap.
Ground pin
Output Feedback Pin. Connect this pin to the center point of the output
resistor divider (as shown in Figure 1) to program the output voltage:
V
OUT
=0.6*(1+R1/R2)
Enable control. Pull high to turn on. Do not float.
Input pin. Decouple this pin to GND pin with at least 1uF ceramic cap
Inductor pin. Connect this pin to the switching node of inductor
a
i
n
Top Mark:
JWxyz for SY8121ABC
,
(Device code: JW, x=year code, y=week code, z= lot number code)
PTxyz for SY8121DEC
,
(Device code: PT, x=year code, y=week code, z= lot number code)
f
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(SOT23-6) (DFN2x2-6)
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AN_SY8121
Block Diagram
IN
BS
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1.5V
c
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p
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d
f
o
PWM
Control &
Protect
Logic
Internal
Power
Input
UVLO
4.5V
FB
0.6V
Internal
SST
Thermal
Protection
r
G
EN
Current Sense
a
i
n
LX
-
P
r
GND
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 3
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AN_SY8121
Electrical Characteristics
(
V
IN
= 12V,
V
OUT
= 1.2V,
L
= 2.2uH,
C
OUT
= 10uF,
T
A
= 25°C,
I
OUT
= 1A unless otherwise specified)
y
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Parameter Symbol Test Conditions Min Typ Max Unit
Input Voltage Range V
IN
4.5 18 V
Quiescent Current I
Q
I
OUT
=0,
V
FB
=V
REF
×105% 400 µA
Shutdown Current I
SHDN
EN=0 5 10 µA
Feedback Reference 0.612 V 0.588 0.6
V
REF
Voltage
FB Input Current I
FB
V
FB
=V
IN
-50 50 nA
Top FET RON 0.14 Ω
R
DS(ON)1
Bottom FET RON R
DS(ON)2
0.13 Ω
Bottom FET Valley
I
LIM
2 A
Current Limit
EN Rising Threshold V
ENH
1.5 V
EN Falling Threshold V
ENL
0.4 V
Input UVLO Threshold V
UVLO
4.5 V
On Time T
ON
V
IN
= 12V
,V
OUT
=1.2V,
I
OUT
= 1A
100 ns
Min ON Time 50 ns
Min Off Time 100 ns
Thermal Shutdown Shutdown Temperature(Note4) 150
T
SDN
°C
Threshold
Hysteresis(Note4) 15
Note 1: Stresses beyond “Absolute Maximum Ratings” may cause permanent damage to the device. These are for
stress ratings. 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:
θ
JA is measured in the natural convection at T
A
= 25°C on a low effective single layer thermal conductivity
test board of JEDEC 51-3 thermal measurement standard. Pin 2 of SOT23-6 packages is the case position for
θ
JC
measurement.
Note 3: The device is not guaranteed to function outside its operating conditions.
Note4: Specified by design (not production tested)
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 4
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AN_SY8121
Typical Performance Characteristics
Efficiency vs. Load Current
100
95
)
%
90
(
y
c
n
e
85
i
c
i
f
f
E
80
7V
IN
,5V
OUT
12V
IN
,5V
OUT
75
16V
IN
,5V
OUT
70
00.511.52
Load Current (A)
)
%
(
y
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f
f
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AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 5
S
AN_SY8121
Startup
(V
IN
=12V, V
OUT
=3.3V, I
LOAD
=2A)
Shutdown
(V
IN
=12V, V
OUT
=3.3V, I
LOAD
=2A)
EN 5V/div
EN 5V/div
V
LX
10V/div
V
LX
10V/div
Time (200µs/div)
f
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t
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-
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p
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G
a
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n
Time (200µs/div)
f
o
r
I
L
2A/div
c
e
V
OUT
2V/divV
OUT
2V/div
I
L
2A/div
S
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l
e
r
g
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 6
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AN_SY8121
Operation
SY8121 is a synchronous buck regulator IC that integrates
the PWM control, top and bottom switches on the same die to
minimize the switching transition loss and conduction loss.
With ultra low Rds(on) power switches and proprietary PWM
control, this regulator IC can achieve the highest efficiency
and the highest switch frequency simultaneously to minimize
the external inductor and capacitor size, and thus achieving
the minimum solution footprint.
C
Because of the high integration in the SY8121 IC, the
application circuit based on this regulator IC is rather
simple. Only input capacitor C
IN
, output capacitor C
OUT
,
output inductor L and feedback resistors (R
1
and R
2
)
need to be selected for the targeted applications
specifications.
Feedback resistor dividers R
1
and R
2
:
Choose R
1
and R
2
to program the proper output voltage.
To minimize the power consumption under light loads,
it is desirable to choose large resistance values for both
R
1
and R
2
. A value of between 10kΩ and 1MΩ is
highly recommended for both resistors. If Vout is 3.3V,
R
1
=100k is chosen, then using following equation, R
2
can be calculated to be 22.1k:
o
n
f
i
d
e
n
t
i
a
l
o
r
p
.
R
2
=
0.6V
R
1
.
V
OUT
−0.6V
0.6V
FB
R
2
GND
Input capacitor C
IN
:
The ripple current through input capacitor is calculated
as：
I
CIN_RMS
=I
OUT
⋅D(1−D)
.
To minimize the potential noise problem, place a
typical X5R or better grade ceramic capacitor really
close to the IN and GND pins. Care should be taken to
S
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C
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 7
-
P
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V
OUT
R
1
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Applications Information
r
G
SY8121 provides protection functions such as cycle by
cycle current limiting and thermal shutdown protection.
SY8121 will sense the output voltage conditions for the
fault protection.
minimize the loop area formed by C
IN
, and IN/GND
pins.
In this case, a 4.7uF low ESR ceramic capacitor is
recommended.
Output capacitor C
OUT
:
The output capacitor is selected to handle the output
ripple noise requirements. Both steady state ripple and
transient requirements must be taken into consideration
when selecting this capacitor. For the best performance,
it is recommended to use X5R or better grade ceramic
capacitor greater than 22uF capacitance.
Output inductor L:
There are several considerations in choosing this
inductor.
1) Choose the inductance to provide the desired
ripple current. It is suggested to choose the ripple
current to be about 40% of the maximum output
current. The inductance is calculated as:
V(1−V
OUT
/V
IN,MAX
)
L=
OUT
F
SW
×I
OUT,MAX
×40%
where Fsw is the switching frequency and I
OUT,MAX
is
the maximum load current.
The SY8121 regulator IC is quite tolerant of different
ripple current amplitude. Consequently, the final choice
of inductance can be slightly off the calculation value
without significantly impacting the performance.
2) The saturation current rating of the inductor must
be selected to be greater than the peak inductor
current under full load conditions.
V
OUT
(1-V
OUT
/V
IN
,
MAX
)
I
SAT
,
MIN
>I
OUT
,
MAX
+
2⋅F
SW
⋅L
3) The DCR of the inductor and the core loss at the
switching frequency must be low enough to
achieve the desired efficiency requirement. It is
desirable to choose an inductor with DCR<50mΩ
to achieve a good overall efficiency.
External Boostrap Cap
This capacitor provides the gate driver voltage for
internal high side MOSEFET. A 100nF low ESR
ceramic capacitor connected between BS pin and LX
pin is recommended.
BS
CB
100nF
LX
a
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-
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AN_SY8121
Load Transient Considerations:
The SY8121 regulator IC integrates the compensation
components to achieve good stability and fast transient
responses. In some applications, adding a 22pF ceramic
cap in parallel with R1 may further speed up the load
transient responses and is thus recommended for
applications with large load transient step requirements.
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 8
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AN_SY8121
SOT23-6L Package Outline & PCB layout
1.90
2.80 -3.10
f
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Top View
0.95 TYP
0
.
0
1
-
0
.
1
1.90 TYP
2
.
4
0
c
e
1
.
0
0
f
i
d
e
n
0
.
2
5
R
E
F
t
i
a
l
0
.
1
-
0
.
1
5
-
P
r
Recommended Pad Layout
C
o
n
y
C
S
i
l
Notes:
e
r
g
o
r
p
.
0.3 -0.6
e
p
a
r
e
0.95
0.60
2
.
7
0
-
3
.
0
0
1
.
5
0
-
1
.
7
0
0.30 -0.50
1.0 -1.3
All dimension in MM
All dimension don’t not include mold flash & metal burr
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 9
AN_SY8121
DFN2x2-6 Package outline
r
G
a
i
n
f
o
r
Top View Side View
c
e
o
r
p
.
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y
C
Bottom View Recommended PCB layout
Notes: All dimensions are in millimeters.
All dimensions don’t include mold flash & metal burr.
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 10
AN_SY8121
Taping & Reel Specification
1. SOT23-6 taping orientation
7
.
7
/
8
.
3
3.9/4.1
1.45/1.55
r
G
a
i
n
pitch(mm)
4
4
f
o
r
t
i
a
l
-
P
r
Reel size
(Inch)
7"
7"
c
e
Package
types
Feeding direction
e
r
g
2. Carrier Tape & Reel specification for packages
Reel
Width
Reel
Size
y
C
o
r
p
.
C
S
i
l
Tape width
(mm)
8
8
o
n
f
i
d
e
n
e
p
a
r
e
Reel
width(mm)
8.4
8.4
d
f
o
Trailer
length(mm)
280
400
Leader length Qty per
(mm) reel
160
160
3000
3000
SOT23-6
DFN2x2
3. Others: NA
AN_SY8121 Rev.0.9 Silergy Corp. Confidential-prepared for Internal Use Only 11