EUTECH EUP7961B

EUP7961
1A Ultra Low-Dropout Linear Regulator
DESCRIPTION
FEATURES
The EUP7961 is a 1A low-dropout linear regulator that
provides a low voltage, high current output with
minimum external components. The features include
precision output voltage, ultra-low dropout voltage,
and low ground current.
The EUP7961 operates from an input of 2.5V to 5.5V.
This regulator uses a 1µF ceramic input capacitors and
a 4.7µF ceramic output capacitor to deliver 1A output
current. High bandwidth provides excellent transient
response. It is designed to power digital circuits
requiring low voltage with high currents (i.e., PLDs,
DSPs, microcontrollers, etc.).
Other features include thermal and current limit
protection, a logic-control shutdown mode and an error
flag output that goes low when the output voltage
drops 10% below the nominal value.
It is available in fixed output voltages of 1.5V, 1.8V,
2.5V, 3.3V or adjustable output voltage with a 0.8V
feedback voltage. The adjustable output voltage can be
set from 0.8V to 4.5V.
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APPLICATIONS
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z
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Typical Application Circuit
Figure1.
DS7961
Ver 1.4
Jan. 2009
1A Guaranteed Output Current
300mV Dropout Voltage at 1A Output
Stable with Ceramic Capacitors
±1.8% Output Voltage Accuracy
300µA Low-Ground Pin Current
0.1µA Quiescent Current in Shutdown Mode
Excellent Line and Load Regulation
Thermal Shutdown and Current Limit Protection
Error Flag Indication
Available in SOT223, SOP-8 and SOT-89 Packages
RoHS Compliant and 100% Lead (Pb)-Free
1
Supply for Low-Voltage Digital IC
PC Add-In Cards
High Efficiency Linear Power Supplies
Post Regulator
EUP7961
Block Diagram
Figure2.
Pin Configurations
Package
Type
Pin
Package
Type
Configurations
SOT223-3
SOT223-3 (B)
SOT223-3 (C)
SOT-89
SOP-8
DS7961
Ver 1.4
Jan. 2009
2
Pin
Configurations
EUP7961
Pin Description
SOT-223 SOT-223
SOT-89
(B)
(C)
DESCRIPTION
PIN
SOT-223
VEN
-
-
-
-
1
Enable Input. Logic high=enable, Logic low=shutdown
VIN
1
3
2
3
2
Input Voltage of the LDO
GND
2
1
1
2
5,6,7,8
VOUT
3
2
3
1
3
Output voltage of the LDO
4
ERROR Flag Output. Active-low indicated an output fault
condition
Adjustable Regulator Feedback Input. Connect to resistor
voltage divider
ERROR
-
-
-
-
ADJ
SOP-8
Ground: TAB is connected to ground
Ordering Information
Order Number
Package Type
EUP7961-15BIR1
SOT223
EUP7961-18BIR1
SOT223
EUP7961-25BIR1
SOT223
EUP7961-33BIR1
SOT223
EUP7961B-15BIR1
SOT223
EUP7961B-18BIR1
SOT223
EUP7961B-25BIR1
SOT223
EUP7961B-33BIR1
SOT223
EUP7961C-15BIR1
SOT223
EUP7961C-18BIR1
SOT223
EUP7961C-25BIR1
SOT223
EUP7961C-33BIR1
SOT223
EUP7961-15CIR1
SOT-89
EUP7961-18CIR1
SOT-89
EUP7961-25CIR1
SOT-89
EUP7961-33CIR1
SOT-89
DS7961
Ver 1.4
Jan. 2009
Marking
xxxxx
P7961C
xxxxx
P7961D
xxxxx
P7961B
xxxxx
P7961H
xxxxx
7961CB
xxxxx
7961DB
xxxxx
7961BB
xxxxx
7961HB
xxxxx
7961C
1C
xxxxx
7961C
1D
xxxxx
7961C
1B
xxxxx
7961C
1H
xxxxx
P7961C
xxxxx
P7961D
xxxxx
P7961B
xxxxx
P7961H
3
Operating Temperature Range
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
EUP7961
Ordering Information (continued)
Order Number
Package Type
EUP7961-15DIR1
SOP-8
EUP7961-18DIR1
SOP-8
EUP7961-25DIR1
SOP-8
EUP7961-33DIR1
SOP-8
EUP7961DIR1
SOP-8
Marking
Operating Temperature Range
xxxxx
EUP7961
C
xxxxx
EUP7961
D
xxxxx
EUP7961
B
xxxxx
EUP7961
H
xxxxx
EUP7961
A
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
-40 °C to +85°C
EUP7961- □ □ □ □ □ □
Lead Free Code
1: Lead Free 0: Lead
Packing
R: Tape & Reel
Operating temperature range
I: Industry Standard
Package Type:
B: SOT223
C: SOT89
Output Voltage
DS7961
Ver 1.4
Jan. 2009
4
D: SOP
EUP7961
Absolute Maximum Ratings (1)
VIN,VOUT to GND -------------------------------------------------------------------- -0.3V to 6V
Other Pins to GND ------------------------------------------------------------------ -0.3V to 6V
Package Thermal Resistance
SOT-223, θJA ---------------------------------------------------------------------- 115°C /W
SOP-8, θJA ------------------------------------------------------------------------- 125°C /W
Power Dissipation, PD@TA= +25°C
SOT-223 --------------------------------------------------------------------------0.87W
SOP-8 -----------------------------------------------------------------------------0.8W
Maximum Junction Temperature ---------------------------------------------------+150°C
Storage Temperature --------------------------------------------------------- -65°C to +150°C
Lead Temp (Soldering 10sec.)----------------------------------------------------------+300°C
ESD Rating
2kV
Human Body Model -------------------------------------------------------------------
„
„
„
„
„
„
„
„
Recommended Operating Conditions (2)
„
„
„
Supply Voltage VIN ---------------------------------------------------------------- 2.5V to 5.5V
Enable Input Voltage -------------------------------------------------------------0V to 5.5V
Operating Temperature Range ---------------------------------------------40°C to +85°C
Note (1): Stress beyond those listed under “Absolute Maximum Ratings” may damage the device.
Note (2): The device is not guaranteed to function outside the recommended operating conditions.
Electrical Characteristics
Specifications in standard type face are for TA= +25°C, and those with boldface type apply over the full operating
temperature range TA= -40°C to +85°C. VIN=VOUT(NOM)+1V, VEN=5V, IL=10mA, CIN=COUT=4.7µF unless
otherwise specified.
Symbol
ΔVOUT
Parameter
VOUT+1V ≤ VIN ≤ 5.5V
10mA ≤ IL ≤ 1A TA= +25°C
Output Voltage Tolerance
VOUT+1V ≤ VIN ≤ 5.5V
10mA ≤ IL ≤ 1A TA= -40°C ~ +85°C
IO(PK)
EUP7961
Min
Typ
Max.
-1.8
1.8
-3
3
Unit
%
Line Regulation
VOUT+1V ≤ VIN ≤ 5.5V
0.1
0.24
%
Load Regulation
10mA ≤ IL ≤ 1A
0.08
0.32
%
IL = 100mA
35
50
IL = 1A
300
500
IL = 10mA
300
360
IL = 1A
500
600
VEN ≤ 0.3V
0.01
10
VIN -VOUT Dropout Voltage
IGND
Conditions
Ground Pin Current in
Normal Operation Mode
Ground Pin Current in
Shutdown Mode
Peak Output Current
VO ≥ VO(NOM) -4%
mV
µA
µA
1.1
1.5
A
1.2
1.7
A
Short Circuit Protection
ISC
DS7961
Short Circuit Current
Ver 1.4
Jan. 2009
5
EUP7961
Electrical Characteristics (continued)
Specifications in standard type face are for TA= +25°C, and those with boldface type apply over the full operating
temperature range TA= -40°C to +85°C. VIN=VOUT(NOM)+1V, VEN=5V, IL=10mA, CIN=COUT=4.7µF unless
otherwise specified.
Symbol
VIH
VIL
Parameter
Enable Threshold
Conditions
Output = High
EUP7961
Min
Typ
Max.
1.4
VIN
Output = Low
0
0.3
TdOFF
Turn-off delay
IL = 1A
20
50
TdON
Turn-on delay
IL = 1A
20
50
VEN Pin Input Current
VEN=VIN
IEN
-1
Unit
V
µs
1
µA
12
%
ERROR Flag
VT
Threshold
VTH
Threshold Hysteresis
VEF(Sat)
Td
ERROR Flag Saturation
8
5
ISINK=100µA
0.02
Flag Reset Delay
ERROR Flag Pin
Leakage Current
ERROR Flag Pin Sink
Imax
Current
AC Parameters
IIK
PSRR
en
Ripple Rejection
Output Noise Voltage
10
VError=0.5V
VIN=VOUT+1V
COUT=10uF
VOUT=3.3V, f=120Hz
BW=10Hz -100kHz
VOUT=2.5V
%
0.1
V
1
µs
1
nA
3.8
mA
60
dB
150
µV(rms)
150
°C
10
°C
Over Temperature Protection
TSH(t)
TSH(h)
DS7961
Shutdown Threshold
Thermal Shutdown
Hysteresis
Ver 1.4
Jan. 2009
6
EUP7961
Typical Operating Characteristics
DS7961
Ver 1.4
Jan. 2009
7
EUP7961
Typical Operating Characteristics (continued)
DS7961
Ver 1.4
Jan. 2009
8
EUP7961
Application Note
Input Capacitor
An input capacitance of 1µF is required between the
EUP7961 input pin and ground (the amount of the
capacitance may be increased without limit).This
capacitor must be located very close to the input pin and
returned to a clean analog ground. Any good quality
ceramic, tantalum, or film capacitor can be used at the
input. If a tantalum capacitor is used at the input, it must
be guaranteed by the manufacturer to have a surge current
rating sufficient for the application. There are no
requirements for the ESR on the input capacitor, but
tolerance and temperature coefficient must be considered
when selecting the capacitor to ensure the capacitance
will be 1µF over the entire operating temperature range.
Output Capacitor
The EUP7961 is designed specifically to work with small
ceramic output capacitors. A ceramic capacitor
(temperature characteristics X7R, X5R, Z5U, or Y5V) in
4.7µF to 22µF range with 5mΩ to 200mΩ ESR range is
suitable in the EUP7961 application circuit.
The output capacitor must meet the requirement for
minimum 4.7µF over the entire operating range and also
have an ESR (Equivalent Series Resistance) value which
is within a stable range (5mΩ to 200mΩ)
voltage is calculated using:
V =V
O
ref
× (1 +
R
R
1)
2
Where:
Vref= 0.8V typ. (the internal reference voltage)
Utilize the following equation for adjusting the output to
a particular voltage:

 V
PI = R  O − 1
2 0.8V


Choose R2=50k to optimize accuracy, power supply
rejection, noise and power consumption.
No-Load Stability
The EUP7961 will remain stable and in regulation with
no external load. This is specially important in CMOS
RAM keep-alive applications.
On/Off Input Operation
The EUP7961 is turned off by pulling the VEN pin low,
and turned on by pulling it high. If this feature is not used,
the VEN pin should be tied to VIN to keep the regulator
output on at all time. To assure proper operation, the
signal source used to drive the VEN input must swing
above and below the specified turn-on/off voltage
thresholds listed in the Electrical Characteristics section
under VIL and VIH.
Power Dissipation
EUP7961 can deliver a continuous current of 2A over the
full operating temperature range. A heatsink may be
required depending on the maximum power dissipation
and maximum ambient temperature of the application.
Under all possible conditions, the junction temperature
must be within the range specified under operating
conditions. The total power dissipation of the device is
given by:
ERROR Flag Operation
The EUP7961 produces a logic low signal at the
ERROR Flag pin when the output drops out of
regulation due to low input voltage, current limiting, or
thermal limiting. This flag has a built in hysteresis.
The ERROR is an open drain output. Hence, the
ERROR pin should be pulled high through a pull up
resistor. The ERROR pin must be connected to ground
if this function is not used. In shutdown, the ERROR
pin is Hi-Z state to save input power.
P = V −V
I
+ V
I
D
IN
IN GND
OUT OUT
Adjustable Operation
The adjustable version of the EUP7961 has an output
voltage range of 0.8V to 4.5V. The output voltage of the
EUP7961 adjustable regulator is programmed using an
external resistor divider as shown in Figure3. The output
DS7961
Ver 1.4
Jan. 2009
9
(
)
( )
Where IGND is the operating ground current of the device
(specified under Electrical Characteristics).
The maximum allowable temperature rise (TRmax)
depends on the maximum ambient temperature (TAmax)
of the application, and the maximum allowable junction
temperature (TJmax):
TRmax= TJmax-TAmax
The maximum allowable value for junction to ambient
Thermal Resistance, θJA , can be calculated using the
formula:
θJA =TRmax/PD
EUP7961
PCB Layout
Good PCB layout practices must be used, otherwise
instability can be induced because of ground loops and
voltages drops. The input and output capacitors must be
directly connected to the input, output, and ground pins
of the regulator using traces which do not have other
currents flowing in them.The best way to do this is to lay
out CIN and COUT near the device with short traces to the
VIN, VOUT, and ground pins. The regulator ground pin
should be connected to the external circuit ground so
that the regulator and its capacitors have a “single point
ground”.
DS7961
Ver 1.4
Jan. 2009
10
EUP7961
Packaging Information
SOT223-3
SYMBOLS
A
A1
B
B1
D
E
e
H
L
DS7961
Ver 1.4
Jan. 2009
MILLIMETERS
MIN.
MAX.
1.50
1.80
0.00
0.10
0.60
0.80
2.90
3.10
6.50
3.50
2.30
6.70
7.30
0.80
1.10
11
INCHES
MIN.
0.059
0.000
0.024
0.114
0.256
0.138
0.090
0.264
0.031
MAX.
0.071
0.004
0.031
0.122
0.287
0.043
EUP7961
SOP-8
SYMBOLS
MILLIMETERS
MIN.
MAX.
MIN.
MAX.
A
1.35
1.75
0.053
0.069
A1
0.10
0.25
0.004
0.010
D
E
4.90
5.80
E1
Ver 1.4
0.193
6.20
0.228
3.90
0.244
0.153
L
0.40
1.27
0.016
0.050
b
0.31
0.51
0.012
0.020
e
DS7961
INCHES
Jan. 2009
1.27
0.050
12
EUP7961
SOT-89
SYMBOLS
A
L
B1
B
C
D
D1
H
E
e
DS7961
Ver 1.4
Jan. 2009
MILLIMETERS
MIN.
MAX.
1.40
1.60
0.89
1.20
0.36
0.48
0.44
0.56
0.35
0.44
4.40
4.60
1.35
1.83
3.94
4.25
2.29
2.60
1.50
13
INCHES
MIN.
0.055
0.035
0.014
0.017
0.014
0.173
0.053
0.155
0.090
0.059
MAX.
0.063
0.047
0.019
0.022
0.017
0.181
0.072
0.167
0.102