Microchip MCP1725T-2502ESN 500 ma, low voltage, low quiescent current ldo regulator Datasheet

MCP1725
500 mA, Low Voltage, Low Quiescent Current LDO Regulator
Features
Description
•
•
•
•
The MCP1725 is a 500 mA Low Dropout (LDO) linear
regulator that provides high current and low output
voltages in a very small package. The MCP1725
comes in a fixed (or adjustable) output voltage version,
with an output voltage range of 0.8V to 5.0V. The
500 mA output current capability, combined with the
low output voltage capability, make the MCP1725 a
good choice for new sub-1.8V output voltage LDO
applications that have high current demands.
•
•
•
•
•
•
•
•
•
•
500 mA 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: 210 mV typical at 500 mA
Typical Output Voltage Tolerance: 0.5%
Stable with 1.0 µF Ceramic Output Capacitor
Fast response to Load Transients
Low Supply Current: 120 µA (typical)
Low Shutdown Supply Current: 0.1 µA (typical)
Adjustable Delay on Power Good Output
Short Circuit Current Limiting and
Overtemperature Protection
2x3 DFN-8 and SOIC-8 Package Options
Applications
•
•
•
•
•
•
•
The MCP1725 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 MCP1725 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 CDELAY pin to
adjust the delay from 200 µs to 300 ms.
High-Speed Driver Chipset Power
Networking Backplane Cards
Notebook Computers
Network Interface Cards
Palmtop Computers
Video Graphics Adapters
2.5V to 1.XV Regulators
The overtemperature and short circuit current-limiting
provide additional protection for the LDO during system
fault conditions.
Package Types
Adjustable (SOIC-8)
VIN 1
VIN 2
SHDN 3
GND 4
8 VOUT
7 ADJ
6 CDELAY
5 PWRGD
Fixed (SOIC-8)
VIN 1
VIN 2
SHDN 3
GND 4
8 VOUT
7 Sense
6 CDELAY
5 PWRGD
Adjustable (2x3 DFN)
VIN 1
VIN 2
SHDN 3
GND 4
© 2007 Microchip Technology Inc.
VOUT
VIN 1
8
VOUT
7
ADJ
VIN 2
7
Sense
6
CDELAY
SHDN 3
6
CDELAY
5
PWRGD
GND 4
5
PWRGD
8
Note:
Fixed (2x3 DFN)
DFN tab is at ground potential.
DS22026B-page 1
MCP1725
Typical Application
MCP1725 Fixed Output Voltage
VIN = 2.3V to 2.8V
C1
4.7 µF
1
VIN
VOUT 8
2
VIN
Sense 7
3
SHDN CDELAY 6
4
GND
VOUT = 1.8V @ 500 mA
C2
1 µF
PWRGD 5
C3
1000 pF
On
R1
100 kΩ
Off
PWRGD
MCP1725 Adjustable Output Voltage
VIN = 2.3V to 2.8V
C1
4.7 µF
1
VIN
VOUT 8
2
VIN
ADJ 7
3
SHDN CDELAY 6
4
GND
VOUT = 1.2V @ 500 mA
R1
40 kΩ
R3
100 kΩ
PWRGD 5
On
Off
C2
1 µF
C3
1000 pF
R2
20 kΩ
PWRGD
DS22026B-page 2
© 2007 Microchip Technology Inc.
MCP1725
Functional Block Diagram - Adjustable Output
PMOS
VIN
VOUT
Undervoltage
Lock Out
(UVLO)
ISNS
Cf
Rf
SHDN
ADJ
Overtemperature
Sensing
+
Driver w/limit
and SHDN
EA
–
SHDN
VREF
V IN
SHDN
Reference
Soft-Start
Comp
TDELAY
PWRGD
GND
92% of VREF
© 2007 Microchip Technology Inc.
CDELAY
DS22026B-page 3
MCP1725
Functional Block Diagram - Fixed Output
PMOS
VIN
VOUT
Undervoltage
Lock Out
(UVLO)
ISNS
Cf
Rf
SHDN
Sense
Overtemperature
Sensing
+
Driver w/limit
and SHDN
EA
–
SHDN
VREF
V IN
SHDN
Reference
Soft-Start
Comp
TDELAY
PWRGD
GND
92% of VREF
DS22026B-page 4
CDELAY
© 2007 Microchip Technology Inc.
MCP1725
1.0
ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings †
VIN ......................................................................... 6.5V
Maximum Voltage on Any Pin
........................................(GND – 0.3V) to (VIN + 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, TJ ................ +150°C
ESD protection on all pins (HBM/MM) .. ≥ 2 kV; ≥ 200V
† Notice: Stresses above those listed under “Maximum
Ratings” 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. Exposure to maximum rating conditions
for extended periods may affect device reliability.
AC/DC CHARACTERISTICS
Electrical Specifications: Unless otherwise noted, VIN = VOUT(MAX) + VDROPOUT(MAX) (Note 1), VR = 1.8V for Adjustable Output,
IOUT = 1 mA, CIN = COUT = 4.7 µF (X7R Ceramic), TA = +25°C.
Boldface type applies for junction temperatures, TJ (Note 7) of -40°C to +125°C
Parameters
Sym
Min
Typ
Max
Input Operating Voltage
VIN
2.3
Input Quiescent Current
Iq
Input Quiescent Current for
SHDN Mode
Maximum Output Current
6.0
V
Note 1
—
120
220
µA
IL = 0 mA, VIN = Note 1,
VOUT = 0.8V to 5.0V
ISHDN
—
0.1
3
µA
SHDN = GND
IOUT
500
—
—
mA
VIN = 2.3V to 6.0V
VR = 0.8V to 5.0V, Note 1
Line Regulation
ΔVOUT/
(VOUT x ΔVIN)
—
±0.05
±0.16
%/V
(Note 1) ≤ VIN ≤ 6V
Load Regulation
ΔVOUT/VOUT
-1.0
±0.5
1.0
%
IOUT = 1 mA to 500 mA,
(Note 4)
IOUT_SC
—
1.2
—
A
RLOAD < 0.1Ω, Peak Current
Output Short Circuit Current
Units
Conditions
Adjust Pin Characteristics (Adjustable Output Only)
Adjust Pin Reference Voltage
VADJ
0.402
0.410
0.418
V
VIN = 2.3V to VIN = 6.0V,
IOUT = 1 mA
Adjust Pin Leakage Current
IADJ
-10
±0.01
+10
nA
VIN = 6.0V, VADJ = 0V to 6V
TCVOUT
—
40
—
ppm/°C
Note 3
V
Note 2
Adjust Temperature Coefficient
Fixed-Output Characteristics (Fixed Output Only)
Voltage Regulation
Note 1:
2:
3:
4:
5:
6:
7:
VOUT
VR - 2.5%
VR ±0.5% VR + 2.5%
The minimum VIN must meet two conditions: VIN ≥ 2.3V and VIN ≥ VOUT(MAX) + VDROPOUT(MAX).
VR is the nominal regulator output voltage for the fixed cases. VR = 1.2V, 1.8V, etc. VR is the desired set point output
voltage for the adjustable cases. VR = VADJ * ((R1/R2)+1). Figure 4-1.
TCVOUT = (VOUT-HIGH – VOUT-LOW) *106 / (VR * ΔTemperature). VOUT-HIGH is the highest voltage measured over the
temperature range. VOUT-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 VOUT = VR + VDROPOUT(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., TA, TJ, θJA). 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.
© 2007 Microchip Technology Inc.
DS22026B-page 5
MCP1725
AC/DC CHARACTERISTICS (CONTINUED)
Electrical Specifications: Unless otherwise noted, VIN = VOUT(MAX) + VDROPOUT(MAX) (Note 1), VR = 1.8V for Adjustable Output,
IOUT = 1 mA, CIN = COUT = 4.7 µF (X7R Ceramic), TA = +25°C.
Boldface type applies for junction temperatures, TJ (Note 7) of -40°C to +125°C
Parameters
Sym
Min
Typ
Max
Units
VIN-VOUT
—
210
350
mV
VPWRGD_VIN
1.0
—
6.0
V
1.2
—
6.0
Conditions
Dropout Characteristics
Dropout Voltage
IOUT = 500 mA, (Note 5)
VIN(MIN) = 2.3V
Power Good Characteristics
PWRGD Input Voltage Operating Range
TA = +25°C
TA = -40°C to +125°C
For VIN < 2.3V, ISINK = 100 µA
PWRGD Threshold Voltage
(Referenced to VOUT)
VPWRGD_TH
—
—
—
89
92
95
%VOUT
Falling Edge
VOUT < 2.5V Fixed, VOUT =
Adj.
90
92
94
VOUT >= 2.5V Fixed
VPWRGD_HYS
1.0
2.0
3.0
%VOUT
PWRGD Output Voltage Low
VPWRGD_L
—
0.2
0.4
V
IPWRGD SINK = 1.2 mA,
ADJ = 0V, SENSE = 0V
PWRGD Leakage
PWRGD_LK
—
1
—
nA
VPWRGD = VIN = 6.0V
PWRGD Threshold Hysteresis
PWRGD Time Delay
Rising Edge
RPULLUP = 10 kΩ
TPG
—
—
10
30
55
ms
CDELAY = 0.01 µF
—
300
—
ms
CDELAY = 0.1 µF
TVDET-PWRGD
—
200
—
µs
VADJ or VSENSE =
VPWRGD_TH + 20 mV to
VPWRGD_TH - 20 mV
Logic High Input
VSHDN-HIGH
45
—
—
%VIN
VIN = 2.3V to 6.0V
Logic Low Input
VSHDN-LOW
—
—
15
%VIN
VIN = 2.3V to 6.0V
SHDNILK
-0.1
±0.001
+0.1
µA
Detect Threshold to PWRGD
Active Time Delay
µs
ICDELAY = 140 nA (Typ)
CDELAY = OPEN
200
Shutdown Input
SHDN Input Leakage Current
Note 1:
2:
3:
4:
5:
6:
7:
VIN = 6V, SHDN =VIN,
SHDN = GND
The minimum VIN must meet two conditions: VIN ≥ 2.3V and VIN ≥ VOUT(MAX) + VDROPOUT(MAX).
VR is the nominal regulator output voltage for the fixed cases. VR = 1.2V, 1.8V, etc. VR is the desired set point output
voltage for the adjustable cases. VR = VADJ * ((R1/R2)+1). Figure 4-1.
TCVOUT = (VOUT-HIGH – VOUT-LOW) *106 / (VR * ΔTemperature). VOUT-HIGH is the highest voltage measured over the
temperature range. VOUT-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 VOUT = VR + VDROPOUT(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., TA, TJ, θJA). 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.
DS22026B-page 6
© 2007 Microchip Technology Inc.
MCP1725
AC/DC CHARACTERISTICS (CONTINUED)
Electrical Specifications: Unless otherwise noted, VIN = VOUT(MAX) + VDROPOUT(MAX) (Note 1), VR = 1.8V for Adjustable Output,
IOUT = 1 mA, CIN = COUT = 4.7 µF (X7R Ceramic), TA = +25°C.
Boldface type applies for junction temperatures, TJ (Note 7) of -40°C to +125°C
Parameters
Sym
Min
Typ
Max
Units
Conditions
TOR
—
100
—
µs
eN
—
2.0
—
µV/√Hz
Power Supply Ripple Rejection
Ratio
PSRR
—
60
—
dB
f = 100 Hz, COUT = 10 µF,
IOUT = 10 mA,
VINAC = 30 mV pk-pk,
CIN = 0 µF
Thermal Shutdown Temperature
TSD
—
150
—
°C
IOUT = 100 µA, VOUT = 1.8V,
VIN = 2.8V
Thermal Shutdown Hysteresis
ΔTSD
—
10
—
°C
IOUT = 100 µA, VOUT = 1.8V,
VIN = 2.8V
AC Performance
Output Delay From SHDN
Output Noise
Note 1:
2:
3:
4:
5:
6:
7:
SHDN = GND to VIN
VOUT = GND to 95% VR
IOUT = 200 mA, f = 1 kHz,
COUT = 10 µF (X7R Ceramic),
VOUT = 2.5V
The minimum VIN must meet two conditions: VIN ≥ 2.3V and VIN ≥ VOUT(MAX) + VDROPOUT(MAX).
VR is the nominal regulator output voltage for the fixed cases. VR = 1.2V, 1.8V, etc. VR is the desired set point output
voltage for the adjustable cases. VR = VADJ * ((R1/R2)+1). Figure 4-1.
TCVOUT = (VOUT-HIGH – VOUT-LOW) *106 / (VR * ΔTemperature). VOUT-HIGH is the highest voltage measured over the
temperature range. VOUT-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 VOUT = VR + VDROPOUT(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., TA, TJ, θJA). 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.
TEMPERATURE SPECIFICATIONS
Electrical Specifications: Unless otherwise indicated, all limits apply for VIN = 2.3V to 6.0V.
Parameters
Sym
Min
Typ
Max
Operating Junction Temperature Range
TJ
Maximum Junction Temperature
TJ
Storage Temperature Range
Units
Conditions
-40
—
+125
°C
Steady State
—
—
+150
°C
Transient
TA
-65
—
+150
°C
Temperature Ranges
Thermal Package Resistances
Thermal Resistance, 8LD 2x3 DFN
Thermal Resistance, 8LD SOIC
© 2007 Microchip Technology Inc.
θJA
—
76
—
°C/W
θJC
—
26
—
°C/W
θJA
—
163
—
°C/W
θJC
—
38.8
—
°C/W
4-Layer JC51-7
Standard Board with
vias
4-Layer JC51-7
Standard Board
DS22026B-page 7
MCP1725
2.0
TYPICAL PERFORMANCE CURVES
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of samples and
are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed.
In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power
supply range) and therefore outside the warranted range.
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA, CIN = COUT =
4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
Note: Junction Temperature (TJ) is approximated by soaking the device under test to an ambient temperature equal to
the desired junction temperature. The test time is small enough such that the rise in Junction Temperature over the
Ambient temperature is not significant.
0.12
IOUT = 0 mA
140
130
+90°C
Line Regulation (%/V)
Quiescent Current (µA)
150
+130°C
120
110
100
0°C
90
+25°C
VIN = 2.3V to 6.0V
0.10
IOUT = 50 mA
0.06
IOUT = 100 mA
0.04
IOUT = 250 mA
0.02
-45°C
80
0.00
2
3
4
5
6
-45
-20
5
Input Voltage (V)
VOUT = 1.2V Adj
200
190
180
170
160
VIN = 2.5V
150
140
VIN = 3.3V
130
VIN = 5.0V
120
0
100
200
300
400
500
0.20
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
VOUT = 5V
IOUT = 1.0 mA to 500 mA
-20
30
55
80
105
130
FIGURE 2-5:
Load Regulation vs.
Temperature (Adjustable Version).
Adjust Pin Voltage (V)
VIN = 6.0V
120
110
VIN = 3.3V
VIN = 2.3V
90
5
0.412
VIN = 5.0V
100
130
VOUT = 0.8V
VOUT = 1.8V
-45
IOUT = 0 mA
130
105
Temperature (°C)
FIGURE 2-2:
Ground Current vs. Load
Current (1.2V Adjustable).
140
80
VOUT = 3.3V
Load Current (mA)
150
55
FIGURE 2-4:
Line Regulation vs.
Temperature (1.8V Adjustable).
Load Regulation (%)
Ground Current (µA)
210
30
Temperature (°C)
FIGURE 2-1:
Quiescent Current vs. Input
Voltage (1.8V Adjustable).
Quiescent Current (µA)
IOUT = 500 mA
IOUT = 1 mA
0.08
80
0.411
IOUT = 1 mA
VIN = 6.0V
VIN = 5.0V
0.410
0.409
VIN = 2.3V, 3.0V, 4.0V
0.408
-45
-20
5
30
55
80
105
130
-45
Temperature (°C)
FIGURE 2-3:
Quiescent Current vs.
Junction Temperature (1.8V Adjustable).
DS22026B-page 8
-20
5
30
55
80
105
130
Temperature (°C)
FIGURE 2-6:
Temperature.
Adjust Pin Voltage vs.
© 2007 Microchip Technology Inc.
MCP1725
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA,
CIN = COUT = 4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
150
VOUT = 5.0V
0.20
0.15
VOUT = 2.5V
0.10
0.05
Quiescent Current (µA)
Dropout Voltage (V)
0.25
0.00
IOUT = 0 mA
140
+130°C
130
120
110
+90°C
100
0°C
90
-45°C
80
0
100
200
300
400
500
2
3
Load Current (mA)
Quiescent Current (µA)
Dropout Voltage (V)
150
0.26
0.24
VOUT = 5.0V
VOUT = 3.3V
0.20
VOUT = 2.5V
0.18
0.16
IOUT = 0 mA
140
130
120
110
+135°C
100
-45°C
+25°C
0°C
-20
5
30
55
80
105
130
3
3.5
Temperature (°C)
+90°C
4.5
5
5.5
6
FIGURE 2-11:
Quiescent Current vs. Input
Voltage (2.5V Fixed).
VIN = 5.0V
VIN = 3.0V
210
Ground Current (µA)
CDELAY = 0.01 µF
IOUT = 0 mA
VIN = 2.3V
4
Input Voltage (V)
FIGURE 2-8:
Dropout Voltage vs.
Temperature (Adjustable Version).
Power Good Time Delay (ms)
6
90
-45
35
34
33
32
31
30
29
28
27
26
25
5
FIGURE 2-10:
Quiescent Current vs. Input
Voltage (0.8V Fixed).
IOUT = 500 mA
0.22
4
Input Voltage (V)
FIGURE 2-7:
Dropout Voltage vs. Load
Current (Adjustable Version).
0.28
+25°C
190
170
VOUT = 5.0V
150
VOUT = 2.5V
130
110
-45
-20
5
30
55
80
105
130
0
© 2007 Microchip Technology Inc.
200
300
400
500
Load Current (mA)
Temperature (°C)
FIGURE 2-9:
Power Good (PWRGD)
Time Delay vs. Temperature (Adjustable
Version).
100
FIGURE 2-12:
Current.
Ground Current vs. Load
DS22026B-page 9
MCP1725
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA,
CIN = COUT = 4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
0.050
IOUT = 0 mA
Line Regulation (%/V)
Quiescent Current (µA)
140
130
120
VOUT = 2.5V
110
100
VOUT = 0.8V
90
80
0.045
0.040
0.035
IOUT = 50 mA
0.030
0.025
0.020
IOUT = 250 mA
0.015
IOUT = 100 mA
-20
5
30
55
80
105
130
-45
-20
5
Junction Temperature (°C)
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
30
80
105
130
FIGURE 2-16:
Line Regulation vs.
Temperature (2.5V Fixed).
0.20
VOUT = 0.8V
IOUT = 1.0 mA to 500 mA
Load Regulation (%)
0.18
VIN = 2.3V
VIN = 6.0V
55
Temperature (°C)
FIGURE 2-13:
Quiescent Current vs.
Junction Temperature.
ISHDN (µA)
IOUT = 500 mA
0.010
-45
VIN = 3.3V
VOUT = 0.8V
0.16
0.14
VOUT = 1.2V
0.12
0.10
0.08
0.06
0.04
0.02
-45
-20
5
30
55
80
105
130
-45
-20
5
Temperature (°C)
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
ISHDN vs. Temperature.
VIN = 2.3V to 6.0V
VOUT = 0.8V
IOUT = 1 mA
30
55
80
105
130
Temperature (°C)
IOUT = 50 mA
IOUT = 100 mA
IOUT = 250 mA
IOUT = 500 mA
FIGURE 2-17:
Load Regulation vs.
Temperature (VOUT < 2.5V Fixed).
0.00
Load Regulation (%)
FIGURE 2-14:
Line Regulation (%/V)
VOUT = 2.5V
VIN = 3.0V to 6.0V
IOUT = 1 mA
IOUT = 1.0 mA to 500 mA
-0.05
VOUT = 2.5V
-0.10
-0.15
VOUT = 5.0V
-0.20
-0.25
-0.30
-0.35
-45
-20
5
30
55
80
105
Temperature (°C)
FIGURE 2-15:
Line Regulation vs.
Temperature (0.8V Fixed).
DS22026B-page 10
130
-45
-20
5
30
55
80
105
130
Temperature (°C)
FIGURE 2-18:
Load Regulation vs.
Temperature (VOUT ≥ 2.5V Fixed).
© 2007 Microchip Technology Inc.
MCP1725
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA,
CIN = COUT = 4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
0.25
10
0.15
Noise (μV/¥Hz)
Dropout Voltage (V)
VOUT = 5.0V
VIN = 3.3V
VOUT = 2.5V
0.20
VOUT = 2.5V
0.10
0.05
0.00
0
100
200
300
400
500
1
0.1
VIN = 2.3V
VOUT = 0.8V
0.01
0.001
0.01
0.1
Load Current (mA)
FIGURE 2-19:
Current.
Dropout Voltage (V)
0.26
100
1000
0
ILOAD = 500 mA
-10
0.24
VOUT = 5.0V
0.22
-20
0.20
VOUT = 2.5V
0.18
0.16
0.14
-30
-40
VR=1.2V Adj
COUT=4.7 μF ceramic X7R
VIN=2.5V
CIN=0 μF
IOUT=10 mA
-50
-60
0.12
-70
0.10
-45
-20
5
30
55
80
105
-80
0.01
130
0.1
Temperature (°C)
FIGURE 2-20:
Temperature.
Dropout Voltage vs.
1.20
100
1000
0
IPEAK
1.10
1
10
Frequency (kHz)
FIGURE 2-23:
Power Supply Ripple
Rejection (PSRR) vs. Frequency (VOUT = 1.2V
Adj.).
-10
VOUT = 2.5V Fixed
CIN = 3000 µF
1.00
0.90
0.80
0.70
ISTEADY STATE
0.60
-20
PSRR (dB)
Short Circuit Current (A)
1
10
Frequency (kHz)
FIGURE 2-22:
Output Noise Voltage
Density vs. Frequency.
PSRR (dB)
0.28
Dropout Voltage vs. Load
ILOAD = 200 mA
COUT = 1 μF
CIN = 10 μF
-30
-40
VR=1.2V Adj
COUT=22 μF ceramic X7R
VIN=2.5V
CIN=0 μF
IOUT=10 mA
-50
-60
-70
0.50
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Input Voltage (V)
FIGURE 2-21:
Input Voltage.
Short Circuit Current vs.
© 2007 Microchip Technology Inc.
-80
0.01
0.1
1
10
Frequency (kHz)
100
1000
FIGURE 2-24:
Power Supply Ripple
Rejection (PSRR) vs. Frequency (VOUT = 1.2V
Adj.).
DS22026B-page 11
MCP1725
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA,
CIN = COUT = 4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
0
-10
PSRR (dB)
-20
-30
-40
VR=2.5V Fixed
COUT=4.7 μF ceramic X7R
VIN=3.3V
CIN=0 μF
IOUT=10 mA
-50
-60
-70
-80
0.01
0.1
1
10
Frequency (KHz)
100
1000
FIGURE 2-25:
Power Supply Ripple
Rejection (PSRR) vs. Frequency (VOUT = 2.5V
Fixed).
FIGURE 2-28:
Shutdown.
2.5V (Adj.) Startup from
0
-10
PSRR (dB)
-20
-30
-40
VR=2.5V Fixed
COUT=22 μF ceramic X7R
VIN=3.3V
CIN=0 μF
IOUT=10 mA
-50
-60
-70
-80
0.01
0.1
1
10
Frequency (KHz)
100
1000
FIGURE 2-26:
Power Supply Ripple
Rejection (PSRR) vs. Frequency (VOUT = 2.5V
Fixed).
FIGURE 2-27:
DS22026B-page 12
2.5V (Adj.) Startup from VIN.
FIGURE 2-29:
Power Good (PWRGD)
Timing with Cdelay of 1000 pF (2.5V Fixed).
FIGURE 2-30:
Power Good (PWRGD)
Timing with CDELAY of 0.01 µF (2.5V Fixed).
© 2007 Microchip Technology Inc.
MCP1725
Note: Unless otherwise indicated, VIN = VOUT + 0.5V or VIN = 2.3V (whichever is greater), IOUT = 1 mA,
CIN = COUT = 4.7 µF Ceramic (X7R), SHDN = VIN, CDELAY = Open, Fixed Output Version, and TA = +25°C.
FIGURE 2-31:
(5.0V Fixed).
Dynamic Line Response
FIGURE 2-33:
Dynamic Load Response
(2.5V Fixed, 1 mA to 500 mA).
FIGURE 2-32:
(2.5V Fixed).
Dynamic Line Response
FIGURE 2-34:
Dynamic Load Response
(2.5V Fixed, 10 mA to 500 mA).
© 2007 Microchip Technology Inc.
DS22026B-page 13
MCP1725
3.0
PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1:
PIN FUNCTION TABLE
Fixed Output
Adjustable
Output
Name
1
1
VIN
Input Voltage Supply
2
2
VIN
Input Voltage Supply
3
3
SHDN
4
4
GND
5
5
PWRGD
Power Good Output (open-drain)
6
6
CDELAY
Power Good Delay Set-Point Input
—
7
ADJ
7
—
Sense
8
8
VOUT
Exposed Pad
Exposed Pad
EP
3.1
Input Voltage Supply (VIN)
Connect the unregulated or regulated input voltage
source to VIN. If the input voltage source is located
several inches away from the LDO, or the input source
is a battery, it is recommended that an input capacitor
be used. A typical input capacitance value of 1 µF to
10 µF should be sufficient for most applications.
3.2
Shutdown Control Input (SHDN)
The SHDN input is used to turn the LDO output voltage
on and off. When the SHDN input is at a logic-high
level, the LDO output voltage is enabled. When the
SHDN input is pulled to a logic-low level, the LDO
output voltage is disabled. When the SHDN input is
pulled low, the PWRGD output also goes low and the
LDO enters a low quiescent current shutdown state
where the typical quiescent current is 0.1 µA.
3.3
Ground (GND)
Description
Shutdown Control Input (active-low)
Ground
Voltage Sense Input (adjustable version)
Voltage Sense Input (fixed voltage version)
Regulated Output Voltage
Exposed Pad of the DFN Package (ground potential)
3.4
Power Good Output (PWRGD)
The PWRGD output is an open-drain output used to
indicate when the LDO output voltage is within 92%
(typically) of its nominal regulation value. The PWRGD
threshold has a typical hysteresis value of 2%. The
PWRGD output is typically delayed by 200 µs (typical,
no capacitance on CDELAY pin) from the time the LDO
output is within 92% + 3% (max hysteresis) of the
regulated output value on power-up. This delay time is
controlled by the CDELAY pin.
3.5
Power Good Delay Set-Point Input
(CDELAY)
The CDELAY input sets the power-up delay time for the
PWRGD output. By connecting an external capacitor
from the CDELAY pin to ground, the typical delay times
for the PWRGD output can be adjusted from 200 µs (no
capacitance) to 300 ms (0.1 µF capacitor). This allows
for the optimal setting of the system reset time.
Connect the GND pin of the LDO to a quiet circuit
ground. This will help the LDO power supply rejection
ratio and noise performance. The ground pin of the
LDO only conducts the quiescent current of the LDO
(typically 120 µA), so a heavy trace is not required.
For applications that have switching or noisy inputs, tie
the GND pin to the return of the output capacitor.
Ground planes help lower inductance and voltage
spikes caused by fast transient load currents and are
recommended for applications that are subjected to
fast load transients.
DS22026B-page 14
© 2007 Microchip Technology Inc.
MCP1725
3.6
3.6.1
Output Voltage Sense/Adjust
Input (ADJ/Sense)
ADJ
For adjustable applications, the output voltage is
connected to the ADJ input through a resistor divider
that sets the output voltage regulation value. This
provides the user the capability to set the output
voltage to any value they desire within the 0.8V to 5.0V
range of the device.
3.6.2
Sense
For fixed output voltage versions of the device, the
SENSE input is used to provide output voltage
feedback to the internal circuitry of the MCP1725. The
SENSE pin typically improves load regulation by
allowing the device to compensate for voltage drops
due to packaging and circuit board layout.
© 2007 Microchip Technology Inc.
3.7
Regulated Output Voltage (VOUT)
The VOUT pin(s) is the regulated output voltage of the
LDO. A minimum output capacitance of 1.0 µF is
required for LDO stability. The MCP1725 is stable with
ceramic,
tantalum
and
aluminum-electrolytic
capacitors. See Section 4.3 “Output Capacitor” for
output capacitor selection guidance.
3.8
Exposed Pad (EP)
The 2x3 DFN package has an exposed pad on the
bottom of the package. This pad should be soldered to
the Printed Circuit Board (PCB) to aid in the removal of
heat from the package during operation. The exposed
pad is at the ground potential of the LDO.
DS22026B-page 15
MCP1725
4.0
DEVICE OVERVIEW
EQUATION 4-2:
The MCP1725 is a high output current, Low Dropout
(LDO) voltage regulator with an adjustable delay
power-good output and shutdown control input. The
low dropout voltage of 210 mV typical at 0.5A of current
makes it ideal for battery-powered applications. Unlike
other high output current LDOs, the MCP1725 only
draws a maximum of 220 µA of quiescent current.
4.1
The MCP1725 LDO is available with either a fixed
output voltage or an adjustable output voltage. The
output voltage range is 0.8V to 5.0V for both versions.
4.1.1
ADJUST INPUT
The adjustable version of the MCP1725 uses the ADJ
pin (pin 7) to get the output voltage feedback for output
voltage regulation. This allows the user to set the
output voltage of the device with two external resistors.
The nominal voltage for ADJ is 0.41V.
Figure 4-1 shows the adjustable version of the
MCP1725. Resistors R1 and R2 form the resistor
divider network necessary to set the output voltage.
With this configuration, the equation for setting VOUT is:
EQUATION 4-1:
R1 + R2
V OUT = V ADJ ⎛ ------------------⎞
⎝ R2 ⎠
Where:
VOUT
=
LDO Output Voltage
VADJ
=
ADJ Pin Voltage
(typically 0.41V)
Where:
4.2
LDO Output Voltage
C1
4.7 µF
VOUT 8
2 VIN
ADJ 7
VOUT
R1
3 SHDN CDELAY 6
On
4 GND
Off
C2
1 µF
PWRGD 5
C3
1000 pF
R2
FIGURE 4-1:
Typical Adjustable Output
Voltage Application Circuit.
The allowable resistance value range for resistor R2 is
from 10 kΩ to 200 kΩ. Solving the equation for R1
yields the following equation:
DS22026B-page 16
=
LDO Output Voltage
VADJ
=
ADJ Pin Voltage
(typically 0.41V)
Output Current and Current
Limiting
The MCP1725 LDO is tested and ensured to supply a
minimum of 0.5A of output current. The MCP1725 has
no minimum output load, so the output load current can
go to 0 mA and the LDO will continue to regulate the
output voltage to within tolerance.
The MCP1725 also incorporates an output current limit.
If the output voltage falls below 0.7V due to an overload
condition (usually represents a shorted load condition),
the output current is limited to 1.2A (typical). If the overload condition is a soft overload, the MCP1725 will
supply higher load currents of up to 1A. The MCP1725
should not be operated in this condition continuously as
it may result in failure of the device. However, this does
allow for device usage in applications that have higher
pulsed load currents having an average output current
value of 0.5A or less.
4.3
1 VIN
VOUT
Output overload conditions may also result in an overtemperature shutdown of the device. If the junction
temperature rises above 150°C, the LDO will shut
down the output voltage. See Section 4.9 “Overtemperature Protection” for more information on
overtemperature shutdown.
MCP1725-ADJ
VIN
V OUT – V ADJ
R 1 = R 2 ⎛ --------------------------------⎞
⎝
⎠
V ADJ
Output Capacitor
The MCP1725 requires a minimum output capacitance
of 1 µF for output voltage stability. Ceramic capacitors
are recommended because of their size, cost and
environmental robustness qualities.
Aluminum-electrolytic and tantalum capacitors can be
used on the LDO output as well. The Equivalent Series
Resistance (ESR) of the electrolytic output capacitor
must be no greater than 1 ohm. The output capacitor
should be located as close to the LDO output as is
practical. Ceramic materials X7R and X5R have low
temperature coefficients and are well within the
acceptable ESR range required. A typical 1 µF X7R
0805 capacitor has an ESR of 50 milli-ohms.
Larger LDO output capacitors can be used with the
MCP1725 to improve dynamic performance and power
supply ripple rejection performance. A maximum of
22 µF
is
recommended.
Aluminum-electrolytic
capacitors are not recommended for low-temperature
applications of < -25°C.
© 2007 Microchip Technology Inc.
MCP1725
4.4
Input Capacitor
Low input source impedance is necessary for the LDO
output to operate properly. When operating from
batteries, or in applications with long lead length
(> 10 inches) between the input source and the LDO,
some input capacitance is recommended. A minimum
of 1.0 µF to 4.7 µF is recommended for most
applications.
For applications that have output step load
requirements, the input capacitance of the LDO is very
important. The input capacitance provides the LDO
with a good local low-impedance source to pull the
transient currents from in order to respond quickly to
the output load step. For good step response
performance, the input capacitor should be of
equivalent (or higher) value than the output capacitor.
The capacitor should be placed as close to the input of
the LDO as is practical. Larger input capacitors will also
help reduce any high-frequency noise on the input and
output of the LDO and reduce the effects of any
inductance that exists between the input source
voltage and the input capacitance of the LDO.
4.5
Power Good Output (PWRGD)
The PWRGD output is used to indicate when the output
voltage of the LDO is within 92% (typical value, see
Section 1.0 “Electrical Characteristics” for Minimum
and Maximum specifications) of its nominal regulation
value.
As the output voltage of the LDO rises, the PWRGD
output will be held low until the output voltage has
exceeded the power good threshold plus the hysteresis
value. Once this threshold has been exceeded, the
power good time delay is started (shown as TPG in
Section 1.0 “Electrical Characteristics”). The power
good time delay is adjustable via the CDELAY pin of the
LDO (see Section 4.6 “CDELAY Input”). By placing a
capacitor from the CDELAY pin to ground, the power
good time delay can be adjusted from 200 µs (no
capacitance) to 300 ms (0.1 µF capacitor). After the
time delay period, the PWRGD output will go high, indicating that the output voltage is stable and within
regulation limits.
The power good output is an open-drain output that can
be pulled up to any voltage that is equal to or less than
the LDO input voltage. This output is capable of sinking
1.2 mA (VPWRGD < 0.4V maximum).
VPWRGD_TH
VOUT
TPG
VOH
TVDET_PWRGD
PWRGD
VOL
FIGURE 4-2:
VIN
Power Good Timing.
TOR
30 µs
SHDN
70 µs
TPG
VOUT
PWRGD
FIGURE 4-3:
Shutdown.
Power Good Timing from
If the output voltage of the LDO falls below the power
good threshold, the power good output will transition
low. The power good circuitry has a 170 µs delay when
detecting a falling output voltage, which helps to
increase noise immunity of the power good output and
avoid false triggering of the power good output during
fast output transients. See Figure 4-2 for power good
timing characteristics.
When the LDO is put into Shutdown mode using the
SHDN input, the power good output is pulled low
immediately, indicating that the output voltage will be
out of regulation. The timing diagram for the power
good output when using the shutdown input is shown in
Figure 4-3.
© 2007 Microchip Technology Inc.
DS22026B-page 17
MCP1725
4.6
CDELAY Input
4.7
The CDELAY input is used to provide the power-up delay
timing for the power good output, as discussed in the
previous section. By adding a capacitor from the
CDELAY pin to ground, the PWRGD power-up time
delay can be adjusted from 200 µs (no capacitance on
CDELAY) to 300 ms (0.1 µF of capacitance on CDELAY).
See Section 1.0 “Electrical Characteristics” for
CDELAY timing tolerances.
Once the power good threshold (rising) has been
reached, the CDELAY pin charges the external capacitor
to VIN. The charging current is 140 nA (typical). The
PWRGD output will transition high when the CDELAY pin
voltage has charged to 0.42V. If the output falls below
the power good threshold limit during the charging time
between 0.0V and 0.42V on the CDELAY pin, the
CDELAY pin voltage will be pulled to ground, thus resetting the timer. The CDELAY pin will be held low until the
output voltage of the LDO has once again risen above
the power good rising threshold. A timing diagram
showing CDELAY, PWRGD and VOUT is shown in
Figure 4-4.
VOUT
VPWRGD_TH
TPG
CDELAY
0V
Shutdown Input (SHDN)
The SHDN input is an active-low input signal that turns
the LDO on and off. The SHDN threshold is a
percentage of the input voltage. The typical value of
this shutdown threshold is 30% of VIN, with minimum
and maximum limits over the entire operating
temperature range of 45% and 15%, respectively.
The SHDN input will ignore low-going pulses (pulses
meant to shut down the LDO) that are up to 400 ns in
pulse width. If the shutdown input is pulled low for more
than 400 ns, the LDO will enter Shutdown mode. This
small bit of filtering helps to reject any system noise
spikes on the shutdown input signal.
On the rising edge of the SHDN input, the shutdown
circuitry has a 30 µs delay before allowing the LDO
output to turn on. This delay helps to reject any false
turn-on signals or noise on the SHDN input signal. After
the 30 µs delay, the LDO output enters its soft-start
period as it rises from 0V to its final regulation value. If
the SHDN input signal is pulled low during the 30 µs
delay period, the timer will be reset and the delay time
will start over again on the next rising edge of the
SHDN input. The total time from the SHDN input going
high (turn-on) to the LDO output being in regulation is
typically 100 µs. See Figure 4-5 for a timing diagram of
the SHDN input.
TOR
VIN (typ)
400 ns (typ)
CDELAY Threshold (0.42V)
30 µs
70 µs
SHDN
PWRGD
VOUT
FIGURE 4-4:
Diagram.
DS22026B-page 18
CDELAY and PWRGD Timing
FIGURE 4-5:
Diagram.
Shutdown Input Timing
© 2007 Microchip Technology Inc.
MCP1725
4.8
Dropout Voltage and
Undervoltage Lockout
Dropout voltage is defined as the input-to-output
voltage differential at which the output voltage drops
2% below the nominal value that was measured with a
VR + 0.6V differential applied. The MCP1725 LDO has
a very low dropout voltage specification of 210 mV
(typical) at 0.5A of output current. See Section 1.0
“Electrical Characteristics” for maximum dropout
voltage specifications.
The MCP1725 LDO operates across an input voltage
range of 2.3V to 6.0V and incorporates input Undervoltage Lockout (UVLO) circuitry that keeps the LDO
output voltage off until the input voltage reaches a
minimum of 2.18V (typical) on the rising edge of the
input voltage. As the input voltage falls, the LDO output
will remain on until the input voltage level reaches
2.04V (typical).
4.9
Overtemperature Protection
The MCP1725 LDO has temperature-sensing circuitry
to prevent the junction temperature from exceeding
approximately 150°C. If the LDO junction temperature
does reach 150°C, the LDO output will be turned off
until the junction temperature cools to approximately
140°C, at which point the LDO output will automatically
resume normal operation. If the internal power
dissipation continues to be excessive, the device will
again shut off. The junction temperature of the die is a
function of power dissipation, ambient temperature and
package thermal resistance. See Section 5.0 “Application Circuits/Issues” for more information on LDO
power dissipation and junction temperature.
Since the MCP1725 LDO undervoltage lockout
activates at 2.04V as the input voltage is falling, the
dropout voltage specification does not apply for output
voltages that are less than 1.9V.
For high-current applications, voltage drops across the
PCB traces must be taken into account. The trace
resistances can cause significant voltage drops
between the input voltage source and the LDO. For
applications with input voltages near 2.3V, these PCB
trace voltage drops can sometimes lower the input
voltage enough to trigger a shutdown due to
undervoltage lockout.
© 2007 Microchip Technology Inc.
DS22026B-page 19
MCP1725
5.0
APPLICATION CIRCUITS/
ISSUES
5.1
Typical Application
In addition to the LDO pass element power dissipation,
there is power dissipation within the MCP1725 as a
result of quiescent or ground current. The power
dissipation as a result of the ground current can be
calculated using the following equation:
The MCP1725 is used for applications that require high
LDO output current and a power good output.
EQUATION 5-2:
P I ( GND ) = V IN ( MAX ) × I VIN
Where:
MCP1725-2.5
VIN = 3.3V
VOUT = 2.5V @ 0.5A
C1
10 µF
1 VIN
VOUT 8
2 VIN
Sense 7
R1
10kΩ
3 SHDN CDELAY 6
C2
10 µF
4 GND PWRGD 5
On
Off
PI(GND
=
Power dissipation due to the
quiescent current of the LDO
VIN(MAX)
=
Maximum input voltage
IVIN
=
Current flowing in the VIN pin
with no LDO output current
(LDO quiescent current)
C3
1000 pF
PWRGD
FIGURE 5-1:
5.1.1
Typical Application Circuit.
APPLICATION CONDITIONS
Package Type
=
2x3 DFN8
Input Voltage Range
=
3.3V ± 5%
5.2
VIN maximum
=
3.465V
VIN minimum
=
3.135V
VDROPOUT (max)
=
0.350V
VOUT (typical)
=
2.5V
IOUT
=
0.5A maximum
PDISS (typical)
=
0.4W
Temperature Rise
=
30.4°C
Power Calculations
5.2.1
POWER DISSIPATION
The internal power dissipation within the MCP1725 is a
function of input voltage, output voltage, output current,
and quiescent current. Equation 5-1 can be used to
calculate the internal power dissipation for the LDO.
The total power dissipated within the MCP1725 is the
sum of the power dissipated in the LDO pass device
and the P(IGND) term. Because of the CMOS
construction, the typical IGND for the MCP1725 is
120 µA. Operating at 3.465V results in a power dissipation of 0.42 milli-Watts. For most applications, this is
small compared to the LDO pass device power
dissipation and can be neglected.
The maximum continuous operating junction
temperature specified for the MCP1725 is +125°C. To
estimate the internal junction temperature of the
MCP1725, the total internal power dissipation is
multiplied by the thermal resistance from junction to
ambient (RθJA) of the device. The thermal resistance
from junction to ambient for the 2x3 DFN package is
estimated at 76° C/W.
EQUATION 5-3:
T J ( MAX ) = P TOTAL × Rθ JA + T AMAX
TJ(MAX) = Maximum continuous junction
temperature
PTOTAL = Total device power dissipation
RθJA = Thermal resistance from junction to
ambient
TAMAX = Maximum ambient temperature
EQUATION 5-1:
P LDO = ( V IN ( MAX ) ) – V OUT ( MIN ) ) × I OUT ( MAX ) )
Where:
PLDO
=
LDO Pass device internal
power dissipation
VIN(MAX)
=
Maximum input voltage
VOUT(MIN)
=
LDO minimum output voltage
DS22026B-page 20
© 2007 Microchip Technology Inc.
MCP1725
The maximum power dissipation capability for a
package can be calculated given the junction-toambient thermal resistance and the maximum ambient
temperature for the application. Equation 5-4 can be
used to determine the package maximum internal
power dissipation.
EQUATION 5-4:
( T J ( MAX ) – T A ( MAX ) )
P D ( MAX ) = --------------------------------------------------Rθ JA
PD(MAX) = Maximum device power dissipation
TJ(MAX) = maximum continuous junction
temperature
5.3
Typical Application
Internal power dissipation, junction temperature rise,
junction temperature and maximum power dissipation
is calculated in the following example. The power dissipation as a result of ground current is small enough to
be neglected.
EXAMPLE 5-1:
Package
Package
Type
EQUATION 5-5:
T J ( RISE ) = P D ( MAX ) × Rθ JA
TJ(RISE) = Rise in device junction temperature
over the ambient temperature
VIN
TJ = Junction temperature
TJ(RISE) = Rise in device junction temperature
over the ambient temperature
TA = Ambient temperature
© 2007 Microchip Technology Inc.
=
3.3V ± 5%
VOUT
=
2.5V
IOUT
=
0.5A
Maximum Ambient Temperature
TA(MAX)
=
60°C
Internal Power Dissipation
PLDO(MAX)
=
(VIN(MAX) – VOUT(MIN)) x
IOUT(MAX)
PLDO
=
((3.3V x 1.05) – (2.5V x 0.975))
x 0.5A
PLDO
=
0.51 Watts
RθJA = Thermal resistance from junction to
ambient
T J = T J ( RISE ) + T A
2x3 DFN
LDO Output Voltage and Current
PD(MAX) = Maximum device power dissipation
EQUATION 5-6:
=
Input Voltage
TA(MAX) = maximum ambient temperature
RθJA = Thermal resistance from junction to
ambient
POWER DISSIPATION
EXAMPLE
5.3.1
DEVICE JUNCTION TEMPERATURE
RISE
The internal junction temperature rise is a function of
internal power dissipation and the thermal resistance
from junction-to-ambient for the application. The
thermal resistance from junction-to-ambient (RθJA) is
derived from an EIA/JEDEC standard for measuring
thermal resistance for small surface-mount packages.
The EIA/JEDEC specification is JESD51-7 “High
Effective Thermal Conductivity Test Board for Leaded
Surface-Mount Packages”. The standard describes the
test method and board specifications for measuring the
thermal resistance from junction to ambient. The actual
thermal resistance for a particular application can vary
depending on many factors such as copper area and
thickness. Refer to AN792, “A Method to Determine
How Much Power a SOT23 Can Dissipate in an Application” (DS00792), for more information regarding this
subject.
TJ(RISE)
=
TJRISE
=
0.51 W x 76.0° C/W
TJRISE
=
38.8°C
PTOTAL x RθJA
DS22026B-page 21
MCP1725
5.3.2
JUNCTION TEMPERATURE
ESTIMATE
To estimate the internal junction temperature, the
calculated temperature rise is added to the ambient or
offset temperature. For this example, the worst-case
junction temperature is estimated below:
5.4
CDELAY Calculations (typical)
ΔT
C = I • ------ΔV
Where:
C
=
CDELAY Capacitor
I
=
CDELAY charging current,
140 nA typical.
ΔT
=
time delay
ΔV
=
CDELAY threshold voltage, 0.42V
typical
TJ = TJRISE + TA(MAX)
TJ = 38.8°C + 60.0°C
TJ = 98.8°C
As you can see from the result, this application will be
operating near around a junction temperature of
100°C. The PCB layout for this application is very
important as it has a significant impact on the junctionto-ambient thermal resistance (RθJA) of the 2x3 DFN
package, which is very important in this application.
5.3.3
MAXIMUM PACKAGE POWER
DISSIPATION AT 60°C AMBIENT
TEMPERATURE
ΔT
– 09
( 140nA • Δ T )
C = I • ------- = ---------------------------------- = 333.3 ×10 • Δ T
ΔV
0.42V
For a delay of 300ms,
C = 333.3E-09 *.300
C = 100E-09 µF (0.1 µF)
2x3 DFN (76°C/W RθJA):
PD(MAX)
=
(125°C – 60°C) / 76°C/W
PD(MAX)
=
0.855W
SOIC8 (163°C/Watt RθJA):
PD(MAX)
=
(125°C – 60°C)/ 163°C/W
PD(MAX)
=
0.399W
From this table, you can see the difference in maximum
allowable power dissipation between the 2x3 DFN
package and the 8-pin SOIC package. This difference
is due to the exposed metal tab on the bottom of the
DFN package. The exposed tab of the DFN package
provides a very good thermal path from the die of the
LDO to the PCB. The PCB then acts like a heatsink,
providing more area to distribute the heat generated by
the LDO.
DS22026B-page 22
© 2007 Microchip Technology Inc.
MCP1725
6.0
PACKAGING INFORMATION
6.1
Package Marking Information
8-Lead DFN (2x3)
Example:
Standard
Extended Temp
XXX
YWW
NN
Code
Voltage
Options *
Code
ABL
750
25
Voltage
Options *
ABL
0.8
ABR
3.0
ABM
1.2
ABS
3.3
ABP
1.8
ABT
5.0
ABQ
2.5
ABU
ADJ
* Custom output voltages available upon request.
Contact your local Microchip sales office for more
information.
8-Lead SOIC (150 mil)
XXXXXXXX
XXXXYYWW
NNN
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
Example:
250802E
e3
SN^^0750
256
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
© 2007 Microchip Technology Inc.
DS22026B-page 23
MCP1725
/HDG3ODVWLF'XDO)ODW1R/HDG3DFNDJH 0& ±[[PP%RG\>')1@
1RWH
)RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW
KWWSZZZPLFURFKLSFRPSDFNDJLQJ
D
e
b
N
N
L
K
E2
E
EXPOSED PAD
NOTE 1
2
1
NOTE 1
1
2
D2
BOTTOM VIEW
TOP VIEW
A
A3
A1
NOTE 2
8QLWV
'LPHQVLRQ/LPLWV
1XPEHURI3LQV
0,//,0(7(56
0,1
1
120
0$;
3LWFK
H
2YHUDOO+HLJKW
$
6WDQGRII
$
&RQWDFW7KLFNQHVV
$
5()
2YHUDOO/HQJWK
'
%6&
2YHUDOO:LGWK
(
([SRVHG3DG/HQJWK
'
±
([SRVHG3DG:LGWK
(
±
E
&RQWDFW/HQJWK
/
&RQWDFWWR([SRVHG3DG
.
±
±
&RQWDFW:LGWK
%6&
%6&
1RWHV
3LQYLVXDOLQGH[IHDWXUHPD\YDU\EXWPXVWEHORFDWHGZLWKLQWKHKDWFKHGDUHD
3DFNDJHPD\KDYHRQHRUPRUHH[SRVHGWLHEDUVDWHQGV
3DFNDJHLVVDZVLQJXODWHG
'LPHQVLRQLQJDQGWROHUDQFLQJSHU$60(<0
%6& %DVLF'LPHQVLRQ7KHRUHWLFDOO\H[DFWYDOXHVKRZQZLWKRXWWROHUDQFHV
5() 5HIHUHQFH'LPHQVLRQXVXDOO\ZLWKRXWWROHUDQFHIRULQIRUPDWLRQSXUSRVHVRQO\
0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &%
DS22026B-page 24
© 2007 Microchip Technology Inc.
MCP1725
/HDG3ODVWLF6PDOO2XWOLQH 61 ±1DUURZPP%RG\>62,&@
1RWH
)RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW
KWWSZZZPLFURFKLSFRPSDFNDJLQJ
D
e
N
E
E1
NOTE 1
1
2
3
α
h
b
h
A2
A
c
φ
L
A1
L1
8QLWV
'LPHQVLRQ/LPLWV
1XPEHURI3LQV
β
0,//,0(7(56
0,1
1
120
0$;
3LWFK
H
2YHUDOO+HLJKW
$
±
%6&
±
0ROGHG3DFNDJH7KLFNQHVV
$
±
±
6WDQGRII†
$
±
2YHUDOO:LGWK
(
0ROGHG3DFNDJH:LGWK
(
%6&
2YHUDOO/HQJWK
'
%6&
%6&
&KDPIHU RSWLRQDO
K
±
)RRW/HQJWK
/
±
)RRWSULQW
/
5()
)RRW$QJOH
ƒ
±
ƒ
/HDG7KLFNQHVV
F
±
/HDG:LGWK
E
±
0ROG'UDIW$QJOH7RS
ƒ
±
ƒ
0ROG'UDIW$QJOH%RWWRP
ƒ
±
ƒ
1RWHV
3LQYLVXDOLQGH[IHDWXUHPD\YDU\EXWPXVWEHORFDWHGZLWKLQWKHKDWFKHGDUHD
†6LJQLILFDQW&KDUDFWHULVWLF
'LPHQVLRQV'DQG(GRQRWLQFOXGHPROGIODVKRUSURWUXVLRQV0ROGIODVKRUSURWUXVLRQVVKDOOQRWH[FHHGPPSHUVLGH
'LPHQVLRQLQJDQGWROHUDQFLQJSHU$60(<0
%6& %DVLF'LPHQVLRQ7KHRUHWLFDOO\H[DFWYDOXHVKRZQZLWKRXWWROHUDQFHV
5() 5HIHUHQFH'LPHQVLRQXVXDOO\ZLWKRXWWROHUDQFHIRULQIRUPDWLRQSXUSRVHVRQO\
0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &%
© 2007 Microchip Technology Inc.
DS22026B-page 25
MCP1725
NOTES:
DS22026B-page 26
© 2007 Microchip Technology Inc.
MCP1725
APPENDIX A:
REVISION HISTORY
Revision B (December 2007)
• Updated Temperature Specifications in
Section 1.0 “Electrical Characteristics”.
• Updated Section 6.0 “Packaging Information”.
• Updated Templates.
Revision A (December 2006)
• Original Release of this Document.
© 2007 Microchip Technology Inc.
DS22026B-page 27
MCP1725
NOTES:
DS22026B-page 28
© 2007 Microchip Technology Inc.
MCP1725
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
Device
XX
X
X
X/
XX
Output Feature Tolerance Temp. Package
Voltage Code
Device:
MCP1725: 500 mA Low Dropout Regulator
MCP1725T: 500 mA Low Dropout Regulator
Tape and Reel
Output Voltage *:
08
12
18
25
30
33
50
=
=
=
=
=
=
=
0.8V “Standard”
1.2V “Standard”
1.8V “Standard”
2.5V “Standard”
3.0V “Standard”
3.3V “Standard”
5.0V “Standard”
*Contact factory for other output voltage options
Extra Feature Code:
0
= Fixed
Tolerance:
2
= 2.0% (Standard)
Temperature:
E
= -40°C to +125°C
Package Type:
MC = Plastic Dual Flat No Lead (DFN) (2x3 Body), 8-lead
SN = Plastic Small Outline (150 mil Body), 8-lead
© 2007 Microchip Technology Inc.
Examples:
a)
MCP1725-0802E/MC:
0.8V Low Dropout
Regulator,
8LD DFN pkg.
b)
MCP1725T-1202E/MC: Tape and Reel,
1.2V Low Dropout
Regulator,
8LD DFN pkg.
c)
MCP1725-1802E/MC:
d)
MCP1725T-2502E/MC: Tape and Reel,
2.5V Low Dropout
Voltage Regulator,
8LD DFN pkg.
e)
MCP1725-3002E/MC:
3.0V Low Dropout
Voltage Regulator,
8LD DFN pkg.
f)
MCP1725-3302E/MC:
3.3V Low Dropout
Voltage Regulator,
8LD DFN pkg.
g)
MCP1725T-5002E/MC: Tape and Reel,
5.0V Low Dropout
Voltage Regulator,
8LD DFN pkg.
h)
MCP1725-ADJE/MC:
i)
MCP1725T-0802E/SN: Tape and Reel,
0.8V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
j)
MCP1725-1202E/SN:
k)
MCP1725T-1802E/SN: Tape and Reel,
1.8V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
l)
MCP1725-2502E/SN:
2.5V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
m)
MCP1725-3002E/SN:
3.0V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
n)
MCP1725-3302E/SN:
3.3V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
o)
MCP1725T-5002E/SN: Tape and Reel,
5.0V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
p)
MCP1725T-ADJE/SN: Tape and Reel,
ADJ Low Dropout
Voltage Regulator,
8LD SOIC pkg.
1.8V Low Dropout
Voltage Regulator,
8LD DFN pkg.
ADJ Low Dropout
Voltage Regulator,
8LD DFN pkg.
1.2V Low Dropout
Voltage Regulator,
8LD SOIC pkg.
DS22026B-page 29
MCP1725
NOTES:
DS22026B-page 30
© 2007 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, Accuron,
dsPIC, KEELOQ, KEELOQ logo, microID, MPLAB, PIC,
PICmicro, PICSTART, PRO MATE, rfPIC and SmartShunt are
registered trademarks of Microchip Technology Incorporated
in the U.S.A. and other countries.
AmpLab, FilterLab, Linear Active Thermistor, Migratable
Memory, MXDEV, MXLAB, SEEVAL, SmartSensor and The
Embedded Control Solutions Company are registered
trademarks of Microchip Technology Incorporated in the
U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, FlexROM, fuzzyLAB,
In-Circuit Serial Programming, ICSP, ICEPIC, Mindi, MiWi,
MPASM, MPLAB Certified logo, MPLIB, MPLINK, PICkit,
PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal,
PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, Select
Mode, Smart Serial, SmartTel, Total Endurance, UNI/O,
WiperLock and ZENA are trademarks of Microchip
Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2007, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
© 2007 Microchip Technology Inc.
DS22026B-page 31
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://support.microchip.com
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Harbour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-4182-8400
Fax: 91-80-4182-8422
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Kokomo
Kokomo, IN
Tel: 765-864-8360
Fax: 765-864-8387
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
China - Fuzhou
Tel: 86-591-8750-3506
Fax: 86-591-8750-3521
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Hsin Chu
Tel: 886-3-572-9526
Fax: 886-3-572-6459
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Shunde
Tel: 86-757-2839-5507
Fax: 86-757-2839-5571
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
10/05/07
DS22026B-page 32
© 2007 Microchip Technology Inc.
Similar pages