Micrel MIC5259-2.85BML 300ma high psrr, low noise î¼cap cmos ldo Datasheet

MIC5259
300mA High PSRR, Low Noise µCap CMOS LDO
General Description
Features
The MIC5259 is an efficient CMOS voltage regulator
optimized for low-noise applications. It offers 1.5% initial
accuracy, low dropout voltage (300mV at 300mA) and low
ground current (typically 105µA at light load). The
MIC5259 provides a very-low-noise output, ideal for RF
applications where a clean voltage source is required. The
MIC5259 has a high PSRR even at low supply voltages,
critical for battery operated electronics. A noise bypass pin
is also available for further reduction of output noise.
Designed specifically for handheld and battery-powered
devices, the MIC5259 provides a TTL-logic-compatible
enable pin. When disabled, power consumption drops to
nearly zero.
The MIC5259 also works with low-ESR ceramic
capacitors, reducing the amount of board space necessary
for power applications; critical issue in handheld wireless
devices.
Key features include current limit, thermal shutdown, faster
transient response, and an active clamp to speed up
device turn-off. The MIC5259 is available in the 6-pin
2mm × 2mm MLF® package and the 5-pin Thin SOT-23
package in a wide range of output voltages.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
•
•
•
•
•
•
•
•
•
•
•
Input voltage range: 2.7V to 6.0V
PSRR = 70dB @ 1kHz
Low output noise: 30µV(rms)
Stability with ceramic output capacitors
Low-dropout: 300mV @ 300mA
High-output accuracy:
– 1.5% initial accuracy
– 3.0% over temperature
Low quiescent current: 105µA
Tight load and line regulation
TTL-Logic-controlled enable input
“Zero” off-mode current
Thermal shutdown and current limit protection
Applications
•
•
•
•
•
•
•
Cellular phones and pagers
Cellular accessories
Battery-powered equipment
Laptop, notebook, and palmtop computers
Consumer/personal electronics
Industrial portable electronics
PC peripherals
Typical Application
CIN = 1.0µF
Ceramic
Enable
Shutdown
VIN MIC5259-x.xBD5/YD5
1
5
2
3
4
COUT = 1.0µF
Ceramic
ENABLE
SHUTDOWN
EN
CIN = 1.0µF
EN
EN (pin 3) may be
connected directly
to IN (pin 1).
VIN
VOUT
VOUT
MIC5259-x.xBML/YML
1
6
2
5
3
4
CBYP
(optional)
COUT = 1.0µF
0.01µF
CBYP = 0.01µF
Ultra-Low Noise Regulator Application
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
September 2006
1
M9999-091406
Micrel, Inc.
MIC5259
Ordering Information(1)
Part Number
Marking
Standard
Pb-Free
Standard
Pb-Free*
Voltage
Junction
Temp. Range**
Package
MIC5259-1.5BD5
MIC5259-1.5YD5
NY15
NY15
1.5V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-1.8BD5
MIC5259-1.8YD5
NY18
NY18
1.8V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-2.5BD5
MIC5259-2.5YD5
NY25
NY25
2.5V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-2.8BD5
MIC5259-2.8YD5
NY28
NY28
2.8V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-2.85BD5
MIC5259-2.85YD5
NY2J
NY2J
2.85V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-3.0BD5
MIC5259-3.0YD5
NY30
NY30
3.0V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-3.3YD5
NY33
MIC5259-3.3BD5
NY33
3.3V
–40°C to +125°C
5-Pin Thin SOT23-5
MIC5259-1.5YML
Y15
1.5V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-1.8YML
Y18
1.8V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-2.1YML
Y21
2.1V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-2.5BML
MIC5259-2.5YML
Y25
Y25
2.5V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-2.8BML
MIC5259-2.8YML
Y28
Y28
2.8V
–40°C to +125°C
6-Pin 2mm x 2mm MLF
MIC5259-2.85BML
MIC5259-2.85YML
Y2J
Y2J
2.85V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-3.0BML
MIC5259-3.0YML
Y30
Y30
3.0V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
MIC5259-3.3BML
MIC5259-3.3YML
Y33
Y33
3.3V
–40°C to +125°C
6-Pin 2mm x 2mm MLF®
*
Under bar / Over bar symbol ( _ /
**
Other voltages available, please contact Micrel Marketing for details.
®
) may not be to scale.
Pin Configuration
EN GND IN
3
2
EN 1
1
6
BYP
5
NC
4
OUT
Yxx
NYxx
NYxx
GND 2
4
5
BYP
OUT
Yxx
IN 3
MIC5259-x.xBD5/YD5
5-Pin Thin SOT-23 (D5)
(Top View)
MIC5259-x.xBML/YML
®
6-Pin 2mm x 2mm MLF (ML)
(Top View)
Pin Description
Pin Number
TSOT-23-5
Pin Number
MLF®-6
Pin Name
1
3
IN
2
2
GND
3
1
EN
4
6
BYP
Reference Bypass: Connect external 0.01µF ≤ CBYP ≤ 1.0µF
capacitor to GND to reduce output noise. May be left open.
5
4
OUT
Regulator Output
―
5
NC
September 2006
Pin Name
Supply Input
Ground
Enable/Shutdown (Input): CMOS compatible input. Logic high =
enable; logic low = shutdown. Do not leave open.
No Connect
2
M9999-091406
Micrel, Inc.
MIC5259
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Input Voltage (VIN).................................... 0V to +7V
Enable Input Voltage (VEN)................................... 0V to +7V
Power Dissipation (PD) ........................... Internally Limited(3)
Junction Temperature (TJ) ........................–40°C to +125°C
Storage Temperature (TS)........................... –65°C to 150°C
Lead Temperature (soldering, 5sec.)......................... 260°C
EDS Rating(4) .................................................................. 2kV
Supply voltage (VIN) ........................................ +2.7V to +6V
Enable Input Voltage (VEN)..................................... 0V to VIN
Junction Temperature (TJ) ........................ –40°C to +125°C
Thermal Resistance
TSOT-23 (θJA)..................................................235°C/W
2x2 MLF® (θJA)...................................................90°C/W
Electrical Characteristics(5)
VIN = VOUT + 1V; VEN = VIN; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C< TJ < +125°C, unless noted.
Symbol
Parameter
Condition
Min
VO
Output Voltage Accuracy
IOUT = 100µA
∆VLRN
∆VLDR
VIN – VOUT
Line Regulation
Load Regulation
Dropout Voltage(7)
VIN = VOUT + 1V to 6V
IOUT = 0.1mA to 300mA(6)
IOUT = 150mA
IOUT = 300mA
–1.5
–3
–0.3
IQ
IGND
Quiescent Current
Ground Pin Current(8)
PSRR
Ripple Rejection; IOUT = 150mA
ILIM
en
Current Limit
Output Voltage Noise
VEN ≤ 0.4V (shutdown)
IOUT = 0mA
IOUT = 300mA
f = 10Hz, COUT = 1.0µF, CBYP = 0.01µF
f = 10Hz, VIN = VOUT + 0.3V
f = 10kHz, VIN = VOUT + 0.3V
VOUT = 0V
350
Typ
0.02
0.6
150
300
0.2
105
120
65
53
53
475
Max
Units
1.5
3
0.3
3.0
%
%
%/V
%
mV
500
550
1
150
250
mV
mV
µA
µA
µA
dB
dB
dB
mA
30
COUT 1.0µF, CBYP = 0.01µF,
f = 10Hz to 100kHz
µV(RMS)
Enable Input
VIL
VIH
IEN
Enable Input Logic-Low Voltage
Enable Input Logic-High Voltage
Enable Input Current
VIN = 2.7 to 5.5V, regulator shutdown
VIN = 2.7V to 5.5V, regulator enabled
VIL ≤ 0.4V, regulator shutdown
VIH ≥ 1.6V, regulator enabled
Shutdown Resistance Discharge
Thermal Protection
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
0.4
1.6
0.01
0.01
500
150
10
1
1
V
V
µA
µA
Ω
°C
°C
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. The maximum allowable power dissipation of any TA (ambient temperature) is PD(max) = (TJ(max) – TA) / θJA. Exceeding the maximum allowable power
dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The θJA of the MIC5259-x.xBM5 (all versions) is
235°C/W on a PC board. See “Thermal Considerations” section for further details.
4. Devices are ESD sensitive. Handling precautions recommended.
5. Specification for packaged product only.
6. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range
from 0.1mA to 300mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
7. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value measured at 1V differential.
For outputs below 2.7V, dropout voltage is the input-to-output voltage differential with the minimum input voltage 2.7V. Minimum input operating
voltage is 2.7V.
8. Ground pin current is the regulator quiescent current. The total current drawn from the supply is the sum of the load current plus the ground pin
current.
September 2006
3
M9999-091406
Micrel, Inc.
MIC5259
Typical Characteristics
September 2006
4
M9999-091406
Micrel, Inc.
MIC5259
Typical Characteristics (cont.)
September 2006
5
M9999-091406
Micrel, Inc.
MIC5259
Functional Characteristics
September 2006
6
M9999-091406
Micrel, Inc.
MIC5259
Functional Diagram
IN
Reference
Voltage
Startup/
Shutdown
Control
Quickstart/
Noise
Cancellation
EN
BYP
Thermal
Sensor
FAULT
Error
Amplifier
Undervoltage
Lockout
Current
Amplifier
OUT
ACTIVE SHUTDOWN
GND
September 2006
7
M9999-091406
Micrel, Inc.
MIC5259
Bypass Capacitor
A capacitor is required from the noise bypass pin to
ground to reduce output voltage noise. The capacitor
bypasses the internal reference. A 0.01µF capacitor is
recommended for applications that require low-noise
outputs. The bypass capacitor can be increased, further
reducing noise and improving PSRR. Turn-on time
increases slightly with respect to bypass capacitance. A
unique quick-start circuit allows the MIC5259 to drive a
large capacitor on the bypass pin without significantly
slowing turn-on time. Refer to the “Typical Characteristics” section for performance with different bypass
capacitors.
Application Information
Enable/Shutdown
The MIC5259 comes with an active-high enable pin that
allows the regulator to be disabled. Forcing the enable
pin low disables the regulator and sends it into a “zero”
off-mode-current state. In this state, current consumed
by the regulator goes nearly to zero. Forcing the enable
pin high enables the output voltage. This part is CMOS
and the enable pin cannot be left floating; a floating
enable pin may cause an indeterminate state on the
output.
Input Capacitor
The MIC5259 is a high performance, high bandwidth
device. Therefore, it requires a well-bypassed input
supply for optimal performance. A 1µF capacitor is
required from the input-to-ground to provide stability.
Low-ESR ceramic capacitors provide optimal performance at a minimum of space. Additional high frequency
capacitors, such as small valued NPO dielectric type
capacitors, help filter out high frequency noise and are
good practice in any RF based circuit.
Active Shutdown
The MIC5259 also features an active shutdown clamp,
which is an N-Channel MOSFET that turns on when the
device is disabled. This allows the output capacitor and
load to discharge, de-energizing the load.
No-Load Stability
The MIC5259 will remain stable and in regulation with no
load unlike many other voltage regulators. This is
especially important in CMOS RAM keep-alive applications.
Output Capacitor
The MIC5259 requires an output capacitor for stability.
The design requires 1µF or greater on the output to
maintain stability. The design is optimized for use with
low-ESR ceramic chip capacitors. High ESR capacitors
may cause high frequency oscillation. The maximum
recommended ESR is 300mΩ. The output capacitor can
be increased, but performance has been optimized for a
1µF ceramic output capacitor and does not improve
significantly with larger capacitance.
X7R/X5R dielectric-type ceramic capacitors are
recommended because of their temperature performance. X7R-type capacitors change capacitance by 15%
over their operating temperature range and are the most
stable type of ceramic capacitors. Z5U and Y5V
dielectric capacitors change value by as much as 50%
and 60%, respectively, over their operating temperature
ranges. To use a ceramic chip capacitor with Y5V
dielectric, the value must be much higher than an X7R
ceramic capacitor to ensure the same minimum
capacitance over the equivalent operating temperature
range.
Thermal Considerations
The MIC5259 is designed to provide 300mA of
continuous current in a very small package. Maximum
power dissipation can be calculated based on the output
current and the voltage drop across the part. To
determine the maximum power dissipation of the
package, use the junction-to-ambient thermal resistance
of the device and the following basic equation:
⎛ TJ(max) − TA
PD(max) = ⎜⎜
θ JA
⎝
⎞
⎟
⎟
⎠
TJ(max) is the maximum junction temperature of the die,
125°C, and TA is the ambient operating temperature.
θJA is layout dependent; Table 1 shows examples of
junction-to-ambient thermal resistance for the MIC5259.
Package
SOT-23-5
(M5 or D5)
MLF (ML)
θJA Recommended
Minimum Footprint
235°C/W
θJA 1” Square
Copper Clad
185°C/W
θJC
145°C/W
90°C/W
Table 1. Thermal Resistance
September 2006
8
M9999-091406
Micrel, Inc.
MIC5259
The junction-to-ambient thermal resistance for the
minimum footprint is 90°C/W, from Table 1. The
maximum power dissipation must not be exceeded for
proper operation. Using the output voltage of 2.8V and
an output current of 200mA, the maximum input voltage
can be determined. Because this device is CMOS and
the ground current is typically 110µA over the load
range, the power dissipation contributed by the ground
current is < 1% and can be ignored for this calculation.
611mW = (VIN – 2.8V) 200mA
611mW = VIN × 200mA – 560mW
1171mW = VIN × 200mA
VIN(max) = 5.85V
Therefore, a 2.8V application at 200mA of output current
can accept a maximum input voltage of 5.85V in an MLF
package. For a full discussion of heat sinking and
thermal effects on voltage regulators, refer to the
“Regulator Thermals” section of Micrel’s Designing with
Low-Dropout Voltage Regulators handbook.
The actual power dissipation of the regulator circuit can
be determined using the equation:
PD = (VIN – VOUT) IOUT + VIN IGND
Substituting PD(max) for PD and solving for the operating
conditions that are critical to the application will give the
maximum operating conditions for the regulator circuit.
For example, when operating the MIC5259-2.8BML at
70°C with a minimum footprint layout, the maximum
input voltage for a set output current can be determined
as follows:
⎛ 125°C − 70°C ⎞
PD(max) = ⎜
⎟
⎝ 90°C/W ⎠
PD(max) = 611mW
September 2006
9
M9999-091406
Micrel, Inc.
MIC5259
Package Information
5-Pin Thin SOT-23 (D5)
6-Pin 2mm x 2mm MLF® (ML)
September 2006
10
M9999-091406
Micrel, Inc.
MIC5259
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http:/www.micrel.com
The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant
into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2004 Micrel, Incorporated.
September 2006
11
M9999-091406
Similar pages