SEMTECH SC4216

SC4216
Very Low Input /Very Low Dropout
3 Amp Regulator With Enable
POWER MANAGEMENT
Description
Features
The SC4216 is a high performance positive voltage
regulator designed for use in applications requiring very
low Input voltage and very low dropout voltage at up to
3 amperes. It operates with a Vin as low as 1.45V, with
output voltage programmable as low as 0.5V. The SC4216
features ultra low dropout, ideal for applications where Vout
is very close to Vin. Additionally, the SC4216 has an enable pin to further reduce power dissipation while shut
down. The SC4216 provides excellent regulation over variations in line, load and temperature.
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Input voltage as low as 1.45V
500mV dropout @ 3A
Adjustable output from 0.5V
Over current and over temperature protection
Enable pin
10µA quiescent current in shutdown
Full industrial temperature range
Available in SOIC-8EDP Lead-free package. This
product is fully WEEE and RoHS compliant
Applications
The SC4216 is available in an SOIC-8EDP (Exposed Die
Pad) package. The output voltage can be set via an
external divider or to fixed settings of 0.5V and 1.2V
depending on how the FB pin is configured.
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Telecom/Networking cards
Motherboards/Peripheral cards
Industrial applications
Wireless infrastructure
Set top boxes
Medical equipment
Notebook computers
Battery powered systems
Typical Application Circuits
SC4216
4
3
VIN
2
ENABLE
1
NC
NC
VIN
VO
EN
FB
NC
GND
5
6
VO
7
8
U1
C1
0.5 (R1 + R2)
=
VO
R1
Volts
R2
C2
R2
SC4216
SC4216
4
3
VIN
2
ENABLE
1
NC
NC
VIN
VO
EN
FB
NC
GND
C1
Revision: March 29, 2006
U1
5
VO
=
0.5
6
4
Volts
3
VIN
VO
7
2
ENABLE
1
8
C1
C2
1
NC
NC
VIN
VO
EN
FB
NC
GND
5
VO
= 1. 2
6
Volts
VO
7
8
C2
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SC4216
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.
Parameter
Symbol
Vin, EN, Vo, FB to GND
Max
Units
7
V
Power Dissipation
PD
Internally Limited
W
Thermal Resistance Junction to Ambient
SOIC-8EDP(1)
θJA
36
°C/W
Thermal Resistance Junction to Case
SOIC-8EDP(1)
θJ C
5.5
°C/W
Operating Ambient Temperature Range
TA
-40 to +85
°C
Operating Junction Temperature Range
TJ
-40 to +125
°C
Storage Temperature Range
TSTG
-65 to +150
°C
Lead Temperature (Soldering) 10 Sec.
TLEAD
300
°C
ESD Rating (Human Body Model)
V ESD
2
kV
Note: (1) 2 square inch of FR-4, double sided, 1 oz. minimum copper weight.
Electrical Characteristics
Unless specified: VEN = VIN, VFB = VO, VIN = 1.45V to 5.5V, VO = VIN -0.5V and IO = 10µA to 3A.
Values in bold apply over the full operating temperature range.
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
5.5
V
3
mA
10
50
µA
VO
+2%
VIN
Supply Voltage Range
VIN
Quiescent Current
IQ
1.45
VIN = 3.3V, IO = 0A
VIN = 5.5V, VEN = 0V
VO
Output Voltage(1)
VO
(Fixed Voltage, VFB = 0)
VIN = VO + 0.5V, IO = 10mA
-2%
Full IO and VIN Range
-3%
+3%
V
Line Regulation(1)
REG(LINE)
IO = 10mA
0.2
0.4
%/V
Load Regulation(1)
REG(LOAD)
10mA ≤ IO ≤ 3A, 1.6V ≤ VIN ≤ 5.5V
0.25
1.0
%
75
150
Dropout Voltage(1)(2)
IO = 500mA
VD
IO = 1A
IO = 1.5A
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200
150
250
300
250
mV
mV
350
400
mV
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SC4216
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: VEN = VIN, VFB = VO, VIN = 1.45V to 5.5V, VO = VIN -0.5V and IO = 10µA to 3A.
Values in bold apply over the full operating temperature range.
Parameter
Symbol
Test Conditions
Min
Typ
Max
300
400
Units
VO (Cont.)
Dropout Voltage(1)(2)
IO = 2A
500
350
IO = 2.5A
450
600
VD
450
IO = 3A
400
500
650
Minimum Load Current(3)
IO
Current Limit
ICL
VIN = VO + 0.5V
mV
550
700
IO = 3A, 1.6V ≤ VIN ≤ 5.5V
mV
mV
mV
10
µA
A
3.5
4.5
5.0
VIN = 3.3V, VFB = VOUT, IO = 10mA
0.495
0.5
0.505
Full IOUT , and VIN Range
0.490
F eed b ack
Reference Voltage(1)
VREF
Feedback Pin Current(4)
Feedback Pin Threshold
IADJ
(5)
VFB = VREF
VTH(FB)
0.05
0.510
V
80
200
nA
0.16
0.40
V
1.5
10
µA
EN
Enable Pin Current
IEN
VEN = 0V, VIN = 3.3V
Enable Pin Threshold
VIH
VIN = 3.3V
VIL
VIN = 3.3V
1.6
V
0.4
Over Temperature Protection
High Trip level
Hysteresis
THI
160
°C
THYST
10
°C
Notes:
(1)
Low duty cycle pulse testing with Kelvin connections required.
(2)
Defined as the input to output differential at which the output voltage drops to 1.5% below the value measured at a
differential of 0.8V.
(3)
Required to maintain regulation. Voltage set resistors R1 and R2 are usually utilized to meet this requirement.
(4)
Guaranteed by design.
(5)
When VFB exceeds this threshold, the “Sense Select” switch disconnects the internal feedback chain from the error
amplifier and connects VFB instead.
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SC4216
POWER MANAGEMENT
Pin Configuration
Ordering Information
Part Number
P ackag e
Temp. Range (TJ)
SC4216STRT(1)(2)
SOIC-8EDP
-40 to +125 OC
S C 4216E V B
Evaluation Board
Notes:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices for the SOIC-8EDP package.
(2) Lead-free product. This product is fully WEEE and
RoHS compliant.
Pin Configuration
Top View
Bottom View
GND
NC
GND
GND
8
EN
FB
FB
7
VIN
VO
VO
6
NC
NC
NC
5
SOIC-8EDP
Exposed
Die Pad
1
NC
2
EN
3
VIN
4
NC
SOIC-8EDP
Pin Descriptions
Pin #
Pin Name Pin Desciption
2
EN
Enable Input. Pulling this pin below 0.4V turns the regulator off, reducing the quiescent current to a
fraction of its operating value. The device will be enabled if this pin is left open. Connect to VIN if not
being used.
3
VIN
Input voltage. For regulation at full load, the input to this pin must be between (VO+ 0.5V) and 5.5V.
Minimum VIN = 1.45V. A large bulk capacitance should be placed closely to this pin to ensure that
the input supply does not sag below 1.45V. Also a minimum of 4.7uF ceramic capacitor should be
placed directly at this pin.
6
VO
The pin is the power output of the device. A minimum of 10uF capacitor should be placed directly at
this pin.
7
FB
When this pin is grounded, an internal resistor divider sets the output voltage to 1.2V. If connected
to the Vo pin, the output voltage will be set at 0.5V. If external feedback resistors are used, the output
voltage will be (See Application Circuits on page 1):
VO
8
GND
1,4,5
NC
=
0.5 (R1 + R2)
R2
Volts
Reference ground.
No Connection.
THERMAL Pad for heatsinking purposes. Connect to ground plane using multiple vias. Not electrically connected
PAD
internally.
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SC4216
POWER MANAGEMENT
Block Diagram
FB
1.5uA
0.5V
8V
REF
Marking Information
SC4216
xxxxxx
yyww
Top View
yyww = Datecode (Example: 0015)
xxxx = Semtech Lot No. (Example: 00101)
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SC4216
POWER MANAGEMENT
Typical Characteristics
Region of Instability
Stable Region
Region of Instability
Region of Instability
Stable Region
Region of Instability
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SC4216
POWER MANAGEMENT
Applications Information
Enable: Pulling this pin below 0.4V turns the regulator off,
reducing the quiescent current to a fraction of its operating value. A pull up resistor up to 400kOhms should be
connected from this pin to the VIN pin in application where
supply voltages of Vin < 1.9V is required. For applications
with higher voltages than 1.9V, EN pin could be left open
or connected to VIN.
Introduction
The SC4216 is intended for applications where high current capability and very low dropout voltage are required.
It provides a very simple, low cost solution that uses very
little pcb real estate. Additional features include an enable pin to allow for a very low power consumption standby
mode, and a fully adjustable output.
Thermal Considerations
Component Selection
The power dissipation in the SC4216 is approximately equal
to the product of the output current and the input to output voltage differential:
Input capacitor: A large bulk capacitance ≥ 10µF/A (output load) should be closely placed to the input supply pin
of the SC4216 to ensure that Vin does not sag below 1.45V.
Also a minimum of 4.7µF ceramic capacitor is recommended to be placed directly next to the Vin pin. 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.
Additional capacitance may be added if required by the
application.
PD ≈ (VIN − VOUT ) • I O
The absolute worst-case dissipation is given by:
PD ( MAX ) = (VIN ( MAX ) − VOUT
( MIN )
)• I
O ( MAX )
+ VIN ( MAX ) • I Q ( MAX )
For a typical scenario, VIN = 3.3V ± 5%, VOUT = 2.8V and
IO = 1.5A, therefore:
Output capacitor: a minimum bulk capacitance of
≥ 10µF/A (output load), along with a 0.1µF ceramic decoupling capacitor is recommended. Increasing the bulk
capacitance will improve the overall transient response.
The use of multiple lower value ceramic capacitors in parallel to achieve the desired bulk capacitance will not cause
stability issues. Although designed for use with ceramic
output capacitors, the SC4216 is extremely tolerant of output capacitor ESR values and thus will also work comfortably with tantalum output capacitors.
VIN(MAX) = 3.465V, VOUT(MIN) = 2.744V and IQ(MAX) = 1.75mA,
Thus PD(MAX) = 1.09W.
Using this figure, and assuming TA(MAX) = 70°C, we can calculate the maximum thermal impedance allowable to maintain TJ ≤ 150°C:
R TH( J − A )(MAX ) =
Noise immunity: in very electrically noisy environments, it
is recommended that 0.1µF ceramic capacitors be placed
from IN to GND and OUT to GND as close to the device pins
as possible.
(T
J( MAX )
− TA (MAX )
PD (MAX )
) = (150 − 70 ) = 73.4° C / W
.
109
This should be achievable for the SOIC-8EDP package using pcb copper area to aid in conducting the heat away,
such as one square inch of copper connected to the exposed die pad of the device. Internal ground/power planes
and air flow will also assist in removing heat. For higher
ambient temperatures it may be necessary to use additional copper area.
Internal voltage selection: By connecting the FB pin to
GND, an internal resistor divider will regulate the output
voltage to 1.2V. If the FB pin is connected directly to the
VO pin, the output voltage will be regulated to the 0.5V
internal reference.
External voltage selection resistors: the use of 1%
resistors, and designing for a current flow ≥ 10µA is
recommended to ensure a well regulated output (thus R2
≤ 50kΩ).
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SC4216
POWER MANAGEMENT
Outline Drawing - SOIC-8EDP
A
D
e
N
2X E/2
1
2
ccc C
2X N/2 TIPS
e/2
B
D
aaa C
A2 A
C
A1
bxN
bbb
.053
.069
.000
.005
.049
.065
.012
.020
.007
.010
.189 .193 .197
.150 .154 .157
.236 BSC
.050 BSC
.086 .090 .094
.010
.020
.016 .028 .041
(.041)
8
0°
8°
.004
.010
.008
A
A1
A2
b
c
D
E1
E
e
F
h
L
L1
N
01
aaa
bbb
ccc
E1 E
SEATING
PLANE
DIMENSIONS
INCHES
MILLIMETERS
MIN NOM MAX MIN NOM MAX
DIM
1.35
1.75
0.00
0.13
1.25
1.65
0.31
0.51
0.17
0.25
4.80 4.90 5.00
3.80 3.90 4.00
6.00 BSC
1.27 BSC
2.19 2.29 2.39
0.25
0.50
0.40 0.72 1.04
(1.05)
8
0°
8°
0.10
0.25
0.20
C A-B D
h
F
EXPOSED PAD
h
H
F
c
GAGE
PLANE
0.25
L
(L1)
SEE DETAIL
A
DETAIL
01
A
SIDE VIEW
NOTES:
1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS
OR GATE BURRS.
4. REFERENCE JEDEC STD MS-012, VARIATION BA.
Land Pattern - SOIC-8EDP
SOLDER MASK
E
D
DIM
(C)
G
F
C
D
E
F
G
P
X
Y
Z
Z
Y
THERMAL VIA
Ø 0.36mm
P
X
DIMENSIONS
INCHES
MILLIMETERS
(.205)
.098
.201
.096
.118
.050
.024
.087
.291
(5.20)
2.49
5.10
2.44
3.00
1.27
0.60
2.20
7.40
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
2. REFERENCE IPC-SM-782A, RLP NO. 300A.
3. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD
SHALL BE CONNECTED TO A SYSTEM GROUND PLANE.
FAILURE TO DO SO MAY COMPROMISE THE THERMAL AND/OR
FUNCTIONAL PERFORMANCE OF THE DEVICE.
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SC4216
POWER MANAGEMENT
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
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