MCP1727
1.5A, Low Voltage, Low Quiescent Current LDO Regulator
Features
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1.5A Output Current Capability
Input Operating Voltage Range: 2.3V to 6.0V
Adjustable Output Voltage Range: 0.8V to 5.0V
Standard Fixed Output Voltages:
- 0.8V, 1.2V, 1.8V, 2.5V, 3.0V, 3.3V, 5.0V
Other Fixed Output Voltage Options Available
Upon Request
Low Dropout Voltage: 330 mV Typical at 1.5A
Typical Output Voltage Tolerance: 0.5%
Stable with 1.0 µF Ceramic Output Capacitor
Fast response to Load Transients
Low Supply Current: 120 µA (typ)
Low Shutdown Supply Current: 0.1 µA (typ)
Adjustable Delay on Power Good Output
Short Circuit Current Limiting and
Overtemperature Protection
3x3 DFN-8 and SOIC-8 Package Options
Description
The MCP1727 is a 1.5A Low Dropout (LDO) linear
regulator that provides high current and low output
voltages in a very small package. The MCP1727
comes in a fixed (or adjustable) output voltage version,
with an output voltage range of 0.8V to 5.0V. The 1.5A
output current capability, combined with the low output
voltage capability, make the MCP1727 a good choice
for new sub-1.8V output voltage LDO applications that
have high current demands.
The MCP1727 is stable using ceramic output
capacitors that inherently provide lower output noise
and reduce the size and cost of the entire regulator
solution. Only 1 µF of output capacitance is needed to
stabilize the LDO.
Using CMOS construction, the quiescent current
consumed by the MCP1727 is typically less than
120 µA over the entire input voltage range, making it
attractive for portable computing applications that
demand high output current. When shut down, the
quiescent current is reduced to less than 0.1 µA.
The scaled-down output voltage is internally monitored
and a power good (PWRGD) output is provided when
the output is within 92% of regulation (typical). An
external capacitor can be used on the C
DELAY
pin to
adjust the delay from 200 µs to 300 ms.
The overtemperature and short circuit current-limiting
provide additional protection for the LDO during system
fault conditions.
Applications
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High-Speed Driver Chipset Power
Networking Backplane Cards
Notebook Computers
Network Interface Cards
Palmtop Computers
2.5V to 1.XV Regulators
Package Types
Adjustable (SOIC-8)
V
IN
1
V
IN
2
SHDN 3
GND 4
8 V
OUT
7 ADJ
6 C
DELAY
5 PWRGD
Fixed (SOIC-8)
V
IN
1
V
IN
2
SHDN 3
GND 4
8 V
OUT
7 Sense
Adjustable (3x3 DFN)
V
IN
1
8
7
6
5
V
OUT
ADJ
C
DELAY
PWRGD
Fixed (3x3 DFN)
V
IN
1
V
IN
2
SHDN 3
GND 4
8
7
6
5
V
OUT
Sense
C
DELAY
PWRGD
V
IN
2
6 C
DELAY
SHDN 3
5 PWRGD
GND 4
©
2006 Microchip Technology Inc.
DS21999A-page 1
MCP1727
Typical Application
MCP1727 Fixed Output Voltage
V
IN
= 2.3V to 2.8V
C
1
4.7 µF
1
2
3
4
On
Off
PWRGD
V
IN
V
IN
V
OUT
8
Sense 7
V
OUT
= 1.8V @ 1A
SHDN C
DELAY
6
GND
PWRGD 5
C
3
1000 pF
R
1
100 kΩ
C
2
1 µF
MCP1727 Adjustable Output Voltage
V
IN
= 2.3V to 2.8V
C
1
4.7 µF
V
OUT
= 1.2V @ 1A
R
1
40 kΩ
1
2
3
4
V
IN
V
IN
V
OUT
8
ADJ 7
SHDN C
DELAY
6
GND
PWRGD 5
C
3
1000 pF
R
3
100 kΩ
R
2
20 kΩ
C
2
1 µF
On
Off
PWRGD
DS21999A-page 2
©
2006 Microchip Technology Inc.
MCP1727
Functional Block Diagram - Adjustable Output
PMOS
V
IN
V
OUT
Undervoltage
Lock Out
(UVLO)
I
SNS
C
f
R
f
ADJ
SHDN
Overtemperature
Sensing
Driver w/limit
and SHDN
SHDN
V
REF
V IN
SHDN
Soft-Start
Comp
GND
92% of V
REF
T
DELAY
Reference
+
EA
–
PWRGD
C
DELAY
©
2006 Microchip Technology Inc.
DS21999A-page 3
MCP1727
Functional Block Diagram - Fixed Output
PMOS
V
IN
V
OUT
Undervoltage
Lock Out
(UVLO)
I
SNS
C
f
R
f
Sense
SHDN
Overtemperature
Sensing
Driver w/limit
and SHDN
SHDN
V
REF
V IN
SHDN
Soft-Start
Comp
GND
92% of V
REF
T
DELAY
Reference
+
EA
–
PWRGD
C
DELAY
DS21999A-page 4
©
2006 Microchip Technology Inc.
MCP1727
1.0
ELECTRICAL
CHARACTERISTICS
† Notice:
Stresses above those listed under “Maximum Rat-
ings” may cause permanent damage to the device. This is a
stress rating only and functional operation of the device at
those or any other conditions above those indicated in the
operational listings of this specification is not implied. Expo-
sure to maximum rating conditions for extended periods may
affect device reliability.
Absolute Maximum Ratings †
V
IN
....................................................................................6.5V
Maximum Voltage on Any Pin .. (GND – 0.3V) to (V
DD
+ 0.3)V
Maximum Power Dissipation......... Internally-Limited (Note
6)
Output Short Circuit Duration ................................ Continuous
Storage temperature .....................................-65°C to +150°C
Maximum Junction Temperature, T
J
........................... +150°C
ESD protection on all pins (HBM/MM)
........... ≥
2 kV;
≥
200V
AC/DC CHARACTERISTICS
Electrical Specifications:
Unless otherwise noted, V
IN
= V
OUT(MAX)
+ V
DROPOUT(MAX)
(Note 1),
V
R
=1.8V for Adjustable Output,
I
OUT
= 1 mA, C
IN
= C
OUT
= 4.7 µF (X7R Ceramic), T
A
= +25°C.
Boldface
type applies for junction temperatures, T
J
(Note
7)
of
-40°C to +125°C
Parameters
Input Operating Voltage
Input Quiescent Current
Input Quiescent Current for
SHDN Mode
Maximum Output Current
Line Regulation
Load Regulation
Output Short Circuit Current
Sym
V
IN
I
q
I
SHDN
I
OUT
ΔV
OUT
/
(V
OUT
x
ΔV
IN
)
ΔV
OUT
/V
OUT
I
OUT_SC
Min
2.3
—
—
1.5
—
-1.0
—
120
0.1
—
0.05
±0.5
2.2
Typ
Max
6.0
220
3
—
0.16
1.0
—
Units
V
µA
µA
A
%/V
%
A
Note 1
I
L
= 0 mA, V
IN
=
Note 1,
V
OUT
= 0.8V to 5.0V
SHDN = GND
V
IN
= 2.3V to 6.0V
V
R
= 0.8V to 5.0V,
Note 1
(Note 1)
≤
V
IN
≤
6V
I
OUT
= 1 mA to 1.5A,
V
IN
=
Note 1,
(Note
4)
V
IN
=
Note 1,
R
LOAD
< 0.1Ω,
Peak Current
V
IN
= 2.3V to V
IN
= 6.0V,
I
OUT
= 1 mA
V
IN
= 6.0V, V
ADJ
= 0V to 6V
Note 3
Note 2
Conditions
Adjust Pin Characteristics (Adjustable Output Only)
Adjust Pin Reference Voltage
Adjust Pin Leakage Current
Adjust Temperature Coefficient
Voltage Regulation
Note 1:
2:
3:
4:
5:
6:
V
ADJ
I
ADJ
TCV
OUT
V
OUT
0.402
-10
—
V
R
- 2.5%
0.410
±0.01
40
V
R
±0.5%
0.418
+10
—
V
R
+ 2.5%
V
nA
ppm/°C
V
Fixed-Output Characteristics (Fixed Output Only)
7:
The minimum V
IN
must meet two conditions: V
IN
≥
2.3V and V
IN
≥
V
OUT(MAX)
+
V
DROPOUT(MAX).
V
R
is the nominal regulator output voltage for the fixed cases. V
R
= 1.2V, 1.8V, etc. V
R
is the desired set point output
voltage for the adjustable cases. V
R
= V
ADJ *
((R
1
/R
2
)+1). Figure 4-1.
TCV
OUT
= (V
OUT-HIGH
– V
OUT-LOW
) *10
6
/ (V
R
*
ΔTemperature).
V
OUT-HIGH
is the highest voltage measured over the
temperature range. V
OUT-LOW
is the lowest voltage measured over the temperature range.
Load regulation is measured at a constant junction temperature using low duty-cycle pulse testing. Load regulation is
tested over a load range from 1 mA to the maximum specified output current.
Dropout voltage is defined as the input-to-output voltage differential at which the output voltage drops 2% below its
nominal value that was measured with an input voltage of V
OUT
= V
R
+ V
DROPOUT(MAX)
.
The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction
temperature and the thermal resistance from junction to air. (i.e., T
A
, T
J
,
θ
JA
). Exceeding the maximum allowable power
dissipation will cause the device operating junction temperature to exceed the maximum +150°C rating. Sustained
junction temperatures above 150°C can impact device reliability.
The junction temperature is approximated by soaking the device under test at an ambient temperature equal to the
desired junction temperature. The test time is small enough such that the rise in the junction temperature over the
ambient temperature is not significant.
©
2006 Microchip Technology Inc.
DS21999A-page 5
