查询SC8863-250CSKTR供应商
POWER MANAGEMENT
Description Features
SC8863
150mA Ultra Low Dropout,
Low Noise Regulator
The SC8863 is a low dropout linear regulator that
operates from a +2.5V to +6.0V input range and
delivers up to 150mA. A PMOS pass transistor allows
the low 110µA supply current to remain independent of
load, making these devices ideal for battery operated
portable equipment such as cellular phones, cordless
phones and personal digital assistants.
The SC8863 output voltage can be preset or adjusted
with an external resistor divider. Other features include
low power shutdown, short circuit protection, thermal
shutdown protection and reverse battery protection. The
SC8863 comes in the tiny 5 lead SOT-23 package (lead
free, fully WEEE and RoHS compliant available) and the
ultra low profile 5 lead TSOT-23.
Typical Application Circuits
Guaranteed 150mA output current
Works with ceramic capacitors
Fixed or adjustable output
Very small external components
Low 75µV
output noise
RMS
Very low supply current
Thermal overload protection
Reverse battery protection
Low power shutdown
Full industrial temperature range
Very low profile packaging available (1mm max.
height)
Surface mount packaging (SOT-23-5 and
TSOT-23-5)
Applications
Battery Powered Systems
Cellular Telephones
Cordless Telephones
Personal Digital Assistants
Portable Instrumentation
Modems
PCMCIA cards
U1 SC8863
VIN > VOUT + VD(MAX)
C1
1uF Ceramic
3 4
IN OUT
1
EN
GND
2
SET
VOUT @ IOUT up to 150mA
5
C2
1uF Ceramic
Internally Preset Output Voltage
VIN > VOUT + VD(MAX)
U1 SC8863
3
IN OUT
1
EN
GND
2
C1
1uF Ceramic
Externally Preset Output Voltage
SET
4
5
R1
R2
10k
(1)
VOUT @ IOUT up to 150mA
OUT
C2
2.2uF Ceramic
1R
1250.1V
+•=
2R
Note:
(1) Select R1 and R2 such that the current flowing through them is ≥ 10µA (i.e. R2 ≤ 120kΩ). A value of 10kΩ
is recommended for R2. Please see Component Selection - Externally Set Output on page 7.
Revision: November 8, 2005
1 www.semtech.com
SC8863
POWER MANAGEMENT
Absolute Maximum Ratings
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified
in the Electrical Characteristics section is not implied.
retemaraPlobmySmumixaMstinU
DNGotTES,TUO,NI,NEV
noitaruDtiucriCtrohStuptuOt
egnaRerutarepmeTegarotST
Electrical Characteristics
Unless specified: VIN = 3.6V, V
retemaraPlobmySsnoitidnoCtseTniMpyTxaMstinU
NI
tnerruCylppuSI
= GND, VEN = VIN, TA = 25°C. Values in bold apply over full operating ambient temperature range.
SET
egnaRegatloVylppuSV
NIP
CS
tneibmAotnoitcnuJ,ecnatsiseRlamrehT
esaCotnoitcnuJ,ecnatsiseRlamrehT
egnaRerutarepmeTtneibmAgnitarepOT
egnaRerutarepmeTnoitcnuJgnitarepOT
ces01)gniredloS(erutarepmeTdaeLT
(1)
NI
Q
θ
AJ
θ
CJ
A
J
GTS
DAEL
I
Am0=001031Aµ
TUO
4-58+ot0C°
4-051+ot0C°
7+ot3.0-V
etinifnIs
652W/C°
18W/C°
051+ot56-C°
003C°
5.20.6 V
061
Am05 ≤ I
≤ Am051011061Aµ
TUO
002
V
V0=1000.01Aµ
NE
2
TUO
)2(
egatloVtuptuO
)2(
noitalugeReniL
V
TUO
Am1 ≤ I
GER
)ENIL(
V5.2 ≤ VNI≤ V,V5.5
TUO
≤ V,Am051
I
TUO
Am1=%0.2-V
V1+ ≤ VNI≤ V5.5 %5.3-%5.3+
TUO
V=
TES
I,
TUO
TUO
Am1=501Vm
TUO
%0.2+V
21
)2(
noitalugeRdaoL
GER
)DAOL(
I
TUO
Am05otAm0=01-51-Vm
02-
I
TUO
Am001otAm0=51-02-Vm
52-
2 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: VIN = 3.6V, V
retemaraPlobmySsnoitidnoCtseTniMpyTxaMstinU
)3()2(
egatloVtuoporD
= GND, VEN = VIN, TA = 25°C. Values in bold apply over full operating ambient temperature range.
SET
)2(
).tnoC(noitalugeRdaoL
GER
)DAOL(
V
D
(1)
SC8863
I
TUO
I
TUO
I
TUO
I
TUO
V,Am05otAm0=
V=
TES
TUO
5.2-5.7-Vm
0.51-
V,Am001otAm0=
V=
TES
TUO
5-51-Vm
03-
Am1=1.1Vm
Am05=5509Vm
021
I
TUO
Am001=011081Vm
042
timiLtnerruCI
esioNegatloVtuptuOe
noitcejeRylppuSrewoP
MIL
n
I,zHk99otzH01
I,zHk99otzH01
TUO
RRSPf≤ zHk155Bd
TUO
C,Am05=
C,Am05=
TUO
Fµ1=09Vµ
TUO
Fµ001=57
051 042 053 Am
SMR
oitaR
NE
dlohserhTtupnINEV
)4(
tnerruCsaiBtupnINE
HI
V
LI
I
NE
VNEV=
NI
8.1 V
4.0
0001An
002
TES
dlohserhTtceleS/esneSV
)2(
egatloVecnerefeRTES
egakaeLtupnITESI
)4(
tnerruC
HT
V
TES
Am1 ≤ I
TES
I
TUO
≤ V5.2,Am051 ≤ VNI≤ V5.5 602.1492.1
TUO
V
Am1=522.1052.1572.1V
V3.1=510.0005.2An
TES
02 55 08 Vm
000.5
noitcetorPerutarepmeTrevO
leveLpirThgiHT
siseretsyHT
IH
TSYH
071C°
01C°
Notes:
(1) This device is ESD sensitive. Use of standard ESD handling precautions is required.
(2) Low duty cycle pulse testing with Kelvin connections required.
(3) Defined as the input to output differential at which the output voltage drops 100mV below the value measured
at a differential of 2V.
(4) Guaranteed by design.
3 2005 Semtech Corp. www.semtech.com
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Pin Configuration Ordering Information
SC8863
SOT-23-5 & TSOT-23-5
Block Diagram
Top View
rebmuNtraPegakcaP
)2()1(
RTKSCXXX-3688CS
)3()2()1(
TRTKSCXXX-3688CS
)2()1(
RTKSTXXX-3688CS
)4(
BVEXXX-3688CS
5-32-TOS
5-32-TOS
5-32-TOST
A/N
Notes:
(1) Where -XXX denotes voltage options. Available
voltages are: 2.50V (-250), 2.80V (-280), 3.00V (-300),
and 3.30 (-330)V.
(2) Only available in tape and reel packaging. A reel
contains 3000 devices.
(3) Lead free product. Fully WEEE and RoHS compliant.
(4) Evaluation board for SC8863. Specify output voltage
option and packaging when ordering.
Pin Descriptions
niPemaNniPnoitcnuFniP
1NEVottcennoC.nipelbanehgihevitcA
2DNG.dedeenfigniknistaehrofdesuebnaC.nipdnuorG
3NI.niptupnI
4TUO.Am051otpugnicruos,tuptuorotalugeR
5TES VrofeulavteserpyllanretniehtnistluserdnuorgotnipsihtgnitcennoC
NI
Vsegnahcredividrotsiser
:ot
TUO
OUT
4 2005 Semtech Corp. www.semtech.com
.desugniebtonfi
TUO
1R
+•=
1250.1V
2R
lanretxenaotgnitcennoC.
POWER MANAGEMENT
Typical Characteristics
SC8863
Output Voltage vs.
Output Current
2.86
VIN = 3.6V
2.85
T
= 25°C
J
2.84
2.83
2.82
2.81
(V)
2.80
OUT
V
2.79
2.78
2.77
2.76
2.75
2.74
0 25 50 75 100 125 150
(mA)
I
OUT
SET Reference Voltage vs.
Output Current
1.275
VIN = 3.6V
1.270
T
= 25°C
J
1.265
1.260
1.255
(V)
1.250
SET
V
1.245
1.240
1.235
1.230
1.225
0 25 50 75 100 125 150
I
(mA)
OUT
Output Voltage vs. Junction Temperature
vs. Output Current
2.86
VIN = 3.6V
2.85
2.84
2.83
2.82
2.81
(V)
2.80
OUT
V
2.79
2.78
2.77
2.76
2.75
2.74
-50 -25 0 25 50 75 100 125
(°C)
T
J
SET Reference Voltage vs. Junction
Temperature vs. Output Current
1.290
VIN = 3.6V
1.280
1.270
1.260
(V)
1.250
SET
V
1.240
1.230
1.220
1.210
-50 -25 0 25 50 75 100 125
(°C)
T
J
IO = 1mA
IO = 50mA
IO = 100mA
IO = 150mA
IO = 1mA
IO = 50mA
IO = 100mA
IO = 150mA
Dropout Voltage vs. Output Current
vs. Junction Temperature
250
SET = GND
225
200
175
150
125
(mV)
D
V
100
75
50
25
0
0 25 50 75 100 125 150
I
(mA)
OUT
Line Regulation vs.
Junction Temperature
12
VIN = 2.5V to 5.5V
SET = OUT
10
I
= 1mA
OUT
8
-40°C
25°C
125°C
(mV)
6
(LINE)
REG
4
2
0
-50 -25 0 25 50 75 100 125
(°C)
T
J
5 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
T
A
Typical Characteristics (Cont.)
SC8863
Load Regulation (V
= GND)
SET
vs. Junction Temperature
50
VIN = 3.6V
45
SET = GND
40
35
30
(mV)
25
(LOAD)
20
REG
15
10
5
0
-50 -25 0 25 50 75 100 125
(°C)
T
J
= 0mA to 150mA
I
OUT
= 0mA to 100mA
I
OUT
I
= 0mA to 50mA
OUT
Supply Current vs.
Output Current
120
110
100
90
80
70
60
(µA)
Q
I
50
40
30
20
VIN = 3.6V
10
T
= 25°C
J
0
0 25 50 75 100 125 150
I
(mA)
OUT
Load Regulation (V
SET
= V
OUT
)
vs. Junction Temperature
20.0
VIN = 3 .6 V
SET = OUT
17.5
15.0
12.5
(mV)
10.0
(LOAD)
7.5
REG
5.0
2.5
0.0
-50-250 255075100125
(°C)
T
J
I
= 0mA to 150mA
OUT
I
= 0mA to 100m
OU
I
= 0mA to 50mA
OUT
Supply Current vs.
Junction Temperature
150
VIN = 3.6V
I
= 150mA
OUT
125
100
75
(µA)
Q
I
50
25
0
-50 -25 0 25 50 75 100 125
T
(°C)
J
Current Limit vs.
Junction Temperature
350
VIN = 3.6V
300
250
200
(mA)
LIM
150
I
100
50
0
-50 -25 0 25 50 75 100 125
T
(°C)
J
2.0
VIN = 3.6V
1.8
1.6
1.4
(V)
IL
1.2
, V
IH
V
1.0
0.8
0.6
0.4
-50 -25 0 25 50 75 100 125
Enable Input Threshold vs.
Junction Temperature
T
(°C)
J
V
IH
V
IL
6 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
Typical Characteristics (Cont.)
SC8863
Sense/Select Threshold vs.
Junction Temperature
80
VIN = 3.6V
70
60
50
(mV)
TH
V
40
30
20
-50 -25 0 25 50 75 100 125
T
(°C)
J
Applications Information
Theory Of Operation
The SC8863 is intended for applications where very low
dropout voltage, low supply current and low output noise
are critical. It provides a very simple, low cost solution
that uses very little pcb real estate. Fixed output voltage
options require the use of only two external capacitors
for operation.
Each voltage option has both fixed and adjustable
output voltage modes. Grounding the SET pin (pulling it
below the Sense/Select threshold of 55mV) will connect
the internal resistor divider to the error amplifier
resulting with the internally preset output voltage. If SET
is pulled above this threshold, then the Sense/Select
switch will connect the SET pin to the error amplifier. The
output will be regulated such that the voltage at SET will
equal V
, the SET reference voltage (typically 1.250V).
SET
Output Spectral Noise Density
vs. Frequency
10
1
(µV/√Hz)
n
e
0.1
0.01
0.1 1 10 100
f (kHz)
SC8863-2.8
VIN = 3.6V
= 50mA
I
OUT
= 25°C
T
J
C
= 1µF
OUT
= 100µF
C
OUT
output noise and improve the overall transient response.
Input capacitor: Semtech recommends the use of a 1µF
ceramic capacitor at the input. This allows for the device
being some distance from any bulk capacitance on the
rail. Additionally, input droop due to load transients is
reduced, improving load transient response.
Component Selection - Externally Set Output
Please refer to Figure 1 below. The output voltage can
be externally adjusted anywhere within the range from
1.25V to (V
IN(MIN)
- V
). The output voltage will be in
D(MAX)
accordance with the following equation:
1R
OUT
1250.1V
+•=
2R
An active high enable pin (EN) is provided to allow the
customer to shut down the part and enter an extremely
low power Off-state. A logic Low signal will reduce the
supply current to 0.1nA.
Component Selection - General
Output capacitor: Semtech recommends a minimum
capacitance of 1µF at the output with an equivalent
series resistance (ESR) of <1Ω over temperature.
Ceramic capacitors are ideal for this application.
Increasing the bulk capacitance will further reduce
U1 SC8863
3 4
IN OUT
R1
R2
10k
C2
2.2uF Ceramic
C1
1uF Ceramic
1
EN
GND
2
SET
5
Figure 1: Externally set output
7 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
(
)
(
)
(
)
(
)
Applications Information (Cont.)
SC8863
1% tolerance resistors are recommended. The values of
R1 and R2 should be selected such that the current flow
through them is ≥ 10µA (thus R2 ≤ 120kΩ). At high input
voltages and/or high output currents, stability may be
improved by increasing C2 to 2.2µF and reducing R2 to
10kΩ. See “Component Selection - General” for input
capacitor requirements.
Thermal Considerations
The worst-case power dissipation for this part is given
by:
IVIVVP •+•−=
)MAX(Q)MAX(IN)MAX(OUT)MIN(OUT)MAX(IN)MAX(D
For all practical purposes, it can be reduced to:
IVVP •−=
)MAX(OUT)MIN(OUT)MAX(IN)MAX(D
Looking at a typical application:
V
= 4.2V
IN(MAX)
V
= (3 - 3.5%) = 2.895V worst-case
OUT
I
= 150mA
OUT
TA = 85°C
This gives us:
With the standard SOT-23-5/TSOT-23-5 Land Pattern
shown at the end of this datasheet, and minimum trace
widths, the thermal impedance junction to ambient for
SC8863 is 256°C/W. Thus with no additional heatsinking,
T
= 135°C.
J(MAX)
The junction temperature can be reduced further by the
use of larger trace widths, and connecting pcb copper
area to the GND pin (pin 2), which connectes directly to
the device substrate. Adding approximately one square
inch of pcb copper to pin 2 will reduce θ
approximately 130°C/W and T
to approximately
J(MAX)
TH(J-A)
to
110°C, for example. Lower junction temperatures
improve overall output voltage accuracy. A sample pcb
layout for the Internally Preset Output Voltage circuit on
page 1 is shown in Figure 2 on page 9.
Layout Considerations
While layout for linear devices is generally not as critical
as for a switching application, careful attention to detail
will ensure reliable operation. See Figure 2 on page 9 for
a sample layout.
1) Attaching the part to a larger copper footprint will
enable better heat transfer from the device, especially
on PCBs where there are internal ground and power
planes.
()
)MAX(D
mW196150.0895.22.4P
=•−=
Using this figure, we can calculate the maximum thermal
impedance allowable to maintain T
TT
=θ
)MAX)(AJ(
−
−
P
)MAX(A)MAX(J
=
)MAX(D
≤ 150°C:
J
−
85150
196.0
W/C332
°=
2) Place the input and output capacitors close to the
device for optimal transient response and device
behavior.
3) Connect all ground connections directly to the ground
plane. If there is no ground plane, connect to a common
local ground point before connecting to board ground.
8 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
Applications Information (Cont.)
SC8863
Top Copper
Figure 2: Suggested pcb layout based upon internally preset output voltage application on page 1.
Notes:Notes:
Notes:
Notes:Notes:
(1) All vias go to the ground plane.
(2) Copper area on pin 2 is recommended, but not required. Connect to the ground plane with a via or vias.
Top Silk Screen
Marking Information
Top Mark
SOT-23-5
8XXX
8 = 8863 in SOT-23-5
XXX = voltage option
(examples: 8280 = SC8863-280CSK)
(example: 0108 for week 8 of 2001)
Bottom Mark
yyww
yyww = Date code
Top Mark
TSOT-23-5
T8XX
T8 = 8863 in TSOT-23-5
XX = voltage option
(examples: T828 = SC8863-280TSK)
Bottom Mark
yyww
yyww = Date code
(example: 0108 for week 8 of 2001)
9 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
Outline Drawing - SOT-23-5
SC8863
Outline Drawing - TSOT-23-5
10 2005 Semtech Corp. www.semtech.com
POWER MANAGEMENT
Land Pattern - SOT-23-5 & TSOT-23-5
SC8863
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
11 2005 Semtech Corp. www.semtech.com
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