SEMTECH SC1564

SC1564
Low Dropout 600mA Linear
Regulator in 3mm x 3mm Package
POWER MANAGEMENT
Features

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

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Description
VIN range: 2.7V to 5.5V
Fixed 1.5V or adjustable output voltage
600mA output current
Operate with ceramic capacitors
2μA quiescent current in shutdown
No minimum load current requirement
Over-current and over-temperature protection
Reverse voltage protection
3mm x 3mm x 1mm MLPD-8 package ( WEEE and
RoHS compliant )
The SC1564 is a high performance positive voltage regulator designed for use in applications requiring low
dropout voltages up to 600mA. Since it has superior
dropout characteristics compared to regular LDOs, it
can be used to supply 2.5V on motherboards, or 2.8V on
peripheral cards from the 3.3V supply with no heatsink.
Additionally, the SC1564 has a shutdown pin to further
reduce power dissipation while in shut down mode. The
SC1564 provides excellent regulation in line, load and
temperature variations.
The output voltage of every device can be selected to
be 1.5V or adjusted between 1.2V and 4.55V. The SC1564
comes in a space-saving 3mm x 3mm x 1mm MLPD-8
package.
Applications
Personal digital assistants
Battery powered systems
 Motherboards
 Peripheral cards
 PCMCIA cards


Typical Application Circuit
VIN (3.3V)
VOUT (1.5V)
IN
OUT
CIN
ADJ
Enable
SHDN
COUT
GND
SC1564
February 07, 2008
SC1564
Pin Configuration
Ordering Information
Part Number
SC1564ML-1.5TRT(1)(2)(3)
8
GND
NC
2
7
SHDN
NC
3
6
NC
OUT
4
5
ADJ
IN
1
TOP VIEW
T
SC1564-1.5EVB
Package
3mm x 3mm x 1mm MLPD-8
Evaluation Board
Notes:
(1) Output voltage can be adjusted using external resistors, see
Pin Descriptions.
(2) Only available in tape and reel packaging. A reel contains 3000 devices.
(3) Available in lead-free package only. Device is WEEE and RoHS compliant.
3mm x 3mm x 1mm MLPD-8
θJA = 41°C/W
Marking Information
CB15
yyww
xxxx
TOP MARK
CHAR
ROWS
4/4/4
3
Marking for the 3 x 3mm MLPD 8 Lead Package:
nnnn = Part Number (Example: CB15) - Reference Part No. Code for small MLP
yyww = Datecode (Example: 0752)
xxxx = Semtech Lot No. (Example: E901)
SC1564
Recommended Operating Conditions
Absolute Maximum Ratings
IN Voltage ………………………………… -0.3V to +7V
IN Voltage Range ………………………… 2.7 to 5.5V
OUT Voltage ………………………………… -0.3V to VIN
Maximum Output Current …………………… 600mA
ADJ Voltage ………………………………… -0.3V to VIN
Junction Temperature …………………
SHDN Voltage ……………………………… -0.3V to VIN
-40 to 150°C
Thermal Information
Thermal Resistance, Junction to Ambient(1) …. 41°C/W
Storage Temperature …………………
-65 to +150°C
Peak IR Reflow Temperature (10s to 30s) …… +260°C
Exceeding the above specifications may result in permanent damage to the device or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not recommended.
NOTES:
(1) Calculated from package in still air, mounted to 3” x 4.5”, 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards.
(2) This device is ESD sensitive. Use of standard ESD handling precautions is required.
Electrical Characteristics
Unless specified: VSHDN = 0V, Adjustable mode: (VADJ = VREF), Fixed mode: (VADJ = GND), VIN = 2.7V to 5.5V and IOUT = 10mA to 600mA. Values in bold apply over full
operating temperature range.. TJ= -40°C to 150°C, typical value are at TJ= 25°C.
Parameter
Symbol
Conditions
Min
Typ
Max
Units
5.5
V
Input Supply
IN Voltage Range
VIN
Quiescent Current
IQ
2.7
VIN = 3.3V
85
170
VIN = VSHDN = 5.5V
0.01
2.00
µA
Output
OUT Voltage(1)
(Internal Fixed Voltage)
VOUT
VIN = 3.3V, IOUT = 10mA, TA = 25°C
1.482
1.467
1.500
1.518
1.533
V
Line Regulation(1)(2)
REG(LINE)
VIN = 2.7V to 5.5V, IOUT = 10mA, TJ ≥ 0°C
0.10
0.40
%
Load Regulation(1)
REG(LOAD)
VIN = 2.7V
0.15
0.40
%
1.10
A
Current Limit(1)(3)
0.65
ILM
IOUT = 10mA
IOUT = 100mA
Dropout Voltage(2)
VD
IOUT = 300mA
IOUT = 600mA
1
70
mV
115
185
210
300
425
420
600
835
mV
mV
mV
SC1564
Electrical Characteristics (continued)
Parameter
Symbol
Conditions
Reference Voltage(1)
VREF
VIN = 3.3V, VADJ = VOUT, IOUT = 10mA
ADJ Pin Current(4)
IADJ
VIN = 3.3V, VADJ = VREF
Min
Typ
Max
Units
1.186
1.200
1.214
V
Reference
ADJ Pin Threshold(5)
VADJ-TH
VIN = 3.3V, VADJ = VREF
1.174
0.10
1.226
65
150
nA
0.25
0.40
V
1.5
5.0
µA
Shutdown
SHDN Pin Current
SHDN Pin Threshold
ISHDN
VSHDN = 0V, VIN = 3.3V
VIH
VIN = 3.3V
VIL
VIN = 3.3V
1.8
V
0.4
Over Temperature Protection
High Trip Level
Hysteresis
THI
170
°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% below the value measured at a differential of 0.95V for 2.2V ≤ VOUT ≤ 4.55V
at adjustable mode configuration. Not measurable on outputs less than 2.2V due to minimum VIN constraints. See typical characteristics curves.
(3) Defined as the output current at which the output voltage drops to 2% below the value measured at output current of 10mA.
(4) Guaranteed by design.
(5) When VADJ exceeds this threshold, the “Sense Select” switch disconnects the internal feedback chain from the error amplifier and connects VADJ instead.
SC1564
Typical Characteristics
Quiescent Current vs Junction Temperature

  
 
 
 



  
  

Line Regulation vs Junction Temperature
























 




Load Regulation vs Junction Temperature
  
 
     



  
  








     

























 
 
Output Voltage vs Junction Temperature
Current Limit vs Junction Temperature



  
  

   

   

 
Quiescent Current at Shutdown






 

 

  


  











 













 
SC1564
Typical Characteristics
Dropout Voltage vs Output Voltage
@ Iout= 100mA

ADJ Pin Current vs Junction Temperature

  


  

   
  


  



  



  

















 



SHDN Pin Current vs Junction Temperature
  
  

 

   
  



  





















 







 
Dropout Voltage vs Output Voltage
@ Iout= 600mA
SHDN Pin Threshold vs Junction Temperature

  
  


  
   
  

 
Dropout Voltage vs Output Voltage
@ Iout= 300mA




  













 













 
SC1564
Pin Descriptions
Pin #
Pin Name
Pin Function
1
IN
Input voltage. For regulation at full load, the input to this pin must be between (VOUT + 0.95V) and 5.5V.
Minimum VIN = 2.7V.
2
NC
No connect
3
NC
No connect
4
OUT
This pin is the power output of this device, sourcing up to 600mA.
This pin sets the output voltage when grounded by the set of internal feedback resistors. If
external feedback resistors are used, the output voltage will be:
5
ADJ
VOUT
1.200 ˜ (R 1 R 2 )
˜V
R2
R1: The resistor connected from OUT to ADJ.
R2: The resistor connected from ADJ to GND.
6
NC
7
SHDN
Shutdown Input. Pulling this pin high turns the regulator off, reducing the quiescent current to a fraction
of its operating value (typically < 300nA). The device will be enabled if this pin is pulled below 0.4V. Connect to GND if not being used.
8
GND
Reference ground.
T
Thermal Pad
No connect
Thermal pad for heatsinking purposes. Not connected internally
SC1564
Block Diagram
SC1564
Applications Information
Introduction
Thermal Considerations
The SC1564 is intended for applications such as graphics cards where high current capability and low dropout voltage are required. It provides a very simple, low
cost solution that uses little PCB real estate. Additional
features include a shutdown pin to allow for a very low
power consumption standby mode, and a fully adjustable output.
The power dissipation in the SC1564 is approximately
equal to the product of the output current and the input
to output voltage differential:
Component Selection
For a typical scenario, VIN = 3.3V ± 5%, VOUT = 1.5V and
IOUT = 600mA, therefore:
Input capacitor: A 1µF ceramic capacitor is recommended.
This allows for the device 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.
Output capacitor: A minimum bulk capacitance of 1µF,
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
SC1564 is extremely tolerant of output capacitor ESR
values and thus will also work comfortably with tantalum
output capacitors.
Noise immunity: In very electrically noisy environents, 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.
PO
(VIN VOUT ) ˜ I OUT
The absolute worst-case dissipation is given by:
PO(MAX) = ( VIN(MAX) − VOUT(MIN) ) ⋅ IOUT(MAX) + VIN(MAX) ⋅ IQ(MAX)
VIN(MAX) = 3.465V,
VOUT(MIN) = 1.47V and
IQ(MAX) = 170µA,
Thus PD(MAX) = 1.1976W.
Using this figure, and assuming TA(MAX) = 85°C, we can
calculate the maximum thermal impedance allowable
to maintain TJ ≤ 150°C:
R TH(J A)(MAX)
§ TJ(MAX) TA(MAX) · § 150qC 85qC ·
¸ ¨
¨
¨
¸ © 1.1976W ¸¹
PO(MAX)
©
¹
54.3 qC
W
This should be achievable with the 3mm x 3mm MLPD-8
package using PCB copper area to aid in conducting the
heat away from the device. Internal ground/power planes
and air flow will also assist in removing heat.
External voltage selection resistors: the use of 1% resistors, designed for a current flow ≥ 10µA is recommended
to ensure a well-regulated output (tus, R2 ≤ 120kΩ).
SC1564
Outline Drawing — 3mm x 3mm MLPD-8
A
D
B
DIM
A
A1
A2
b
D
D1
E
E1
e
L
N
aaa
bbb
E
PIN 1
INDICATOR
(LASER MARK)
A
aaa C
D1
1
A1
A2
DIMENSIONS
INCHES
MILLIMETERS
MIN NOM MAX MIN NOM MAX
.031 .035 .039
.000 .001 .002
(.008)
.010 .012 .014
.114 .118 .122
.085
.098
.114 .118 .122
.053
.069
.026 BSC
.012 .016 .020
8
.003
.004
0.80 0.90 1.00
0.00 0.02 0.05
(0.20)
0.25 0.30 0.35
2.90 3.00 3.10
2.15
2.48
2.90 3.00 3.10
1.35
1.75
0.65 BSC
0.30 0.40 0.50
8
0.08
0.10
SEATING
PLANE
C
2
LxN
E/2
E1
N
e
bxN
bbb
C A B
e/2
D/2
NOTES:
1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS.
10
SC1564
Land Pattern — 3mm x 3mm MLPD-8
K
Y
(C)
H
X
DIM
G
Z
DIMENSIONS
INCHES
MILLIMETERS
C
G
H
K
P
X
Y
Z
(.116)
.087
.067
.102
.026
.016
.030
.146
(2.95)
2.20
1.70
2.58
0.65
0.40
0.75
3.70
P
NOTES:
1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
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.
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805) 498-2111 Fax: (805) 498-3804
www.semtech.com
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