MIC69103YML Evaluation Board User Guide

MIC69101/03 Evaluation Board
Low VIN, Low VOUT 1A LDO Regulator
General Description
This evaluation board can be used to evaluate several of
Micrel’s new, low-voltage, high-current, low-dropout linear
voltage regulators. The MIC69101YML is a 1A LDO in a
MLF® package with a fixed output voltage that offers the
added functionality of an enable pin and an error flag
output. The MIC69103YML is an adjustable version of the
MIC69101 in a MLF® package and it also has the added
functionality of an enable pin, allowing the user to disable
the device and put it into a zero-current off mode state.
Requirements
The evaluation board requires a power supply capable of
supplying a minimum of 1A of output current. The
maximum voltage of that power supply should be at least
5V. The evaluation board has jumpers to set the output
voltage to: 3.3V, 2.5V, 1.8V or 1.5V. The output voltage
can also be set to a different value by using the adjustable
version (MIC69103) and by choosing R1 and R2 as
detailed on the right. The MIC69101 has an input voltage
range of 1.65V to 5.5V, therefore it is not limited to just 5V
systems.
Circuit Description
The MIC69101 regulator is simple to implement, requiring
only an output capacitor for proper operation. An input
capacitor is required when the supply is greater than 4
inches away from the device. The evaluation board
includes an input capacitor within 1 inch of the device. This
is the recommended maximum distance away from the
device that a capacitor should be placed.
A minimum of 4.7µF of output capacitance is required for
the MIC69101. Using large values of capacitance at the
input and output will help to improve transient response.
MIC69101/MIC69103
The MIC69101 circuit implements an error flag, an enable
function, and sense pin. The enable function allows the
user to put the device into a zero-current off state when
the regulator is not required. The enable pin is an activehigh pin and needs to be pulled high (≥2V) to enable the
device and pulled low (≤0.8V) to disable the device. The
error flag function is a voltage monitor that indicates when
the output falls out of regulation for any reason. The error
flag output is an open-collector output, which is active-low,
and requires a pull-up resistor for proper operation. R1 is a
zero ohm resistor. All berg jumpers on JP2 must be left
open. Boards assembled with the MIC69101 have a
100kΩ pull-up resistor from FLG to the output voltage.
The MIC69103 is an adjustable regulator that implements
an enable pin that allows the user to disable the device.
The enable pin is also active-high and requires that pin to
be pulled high to turn-on the output and pulled low to
disable the output. A jumper (JP1) is available to tie that
pin to either the input or to ground. The output voltage of
the MIC69103 is adjustable down to 0.5V. The board is
set-up with four set voltage options, A through D. A fifth
option is available that can be custom set. The equation to
set the output voltage is as follows:
R1 ⎞
⎛
VOUT = VREF ⎜1 +
⎟
R2 ⎠
⎝
VREF = 0.5V
On the board as it stands, R1 is set to 10kΩ. Using the
equation and knowing that R1 = 10kΩ, a custom voltage
can be determined by solving for R2 and placing an 0805
or 1206 resistor in the slot prepared and labeled E.
⎛
⎞
VREF
R2 = ⎜⎜
× R1⎟⎟
⎝ VOUT − VRE F
⎠
⎛
⎞
0.5V
R2 = ⎜⎜
× 10k Ω ⎟⎟
⎝ VOUT − 0.5 V
⎠
Leaving all jumpers open sets the output voltage to 0.5V.
The MIC69103YML adjustable output evaluation board
can be configured into a fixed output version in the
following way:
R1 = zero ohms
Remove R2, R3, R4, R5
Remove all jumpers from JP2
Replace U1 with MIC69101YML
Minimum Load
All of the devices require a minimum load of 10mA. A
resistor is included on the board to provide a minimum
load of 10mA. The resistor value is different depending on
the voltage option that the board has. The MIC69101 has
a 140Ω resistor to maintain approximately 10mA at 1.4V
output voltage. The 140Ω resistor can be changed to set a
10mA load depending upon the desired output voltage.
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
May 2008
M9999-052908-A
Micrel, Inc.
MIC69101/03 Evaluation Board
Ordering Information
Part Number
Description
MIC69103YML EV
Evaluation board with the
adjustable output MIC69103 device
with Enable and Error Flag pins
Evaluation Board Schematic
U1
MIC69101/03YML
J1
VIN
J2
GND
7
VIN
VOUT
9
C1
10µF/6.3V
R6
100k
J3
FLG
R1
10k
ADJ/SNS
FLG
J5
GND
10
J6
ADJ/SNS
3
1
J4
VOUT
C2
4.7µF/6.3V
2
6
EN
R2
4.99k
R3
3.83k
R4
2.49k
R5
1.78k
A
B
C
D
3
6
4
2
3
1
JP2: Voltages Selector
A: VOUT = 1.5V
B: VOUT = 1.8V
C: VOUT = 2.5V
D: VOUT = 3.3V
JP2
Header 4X2
Option for Adjustable VOUT (MIC69103YML)
R1 = 10k
Select desired output voltage with berg jumper on JP2
Option for Fixed VOUT (MIC69101YML)
R2, R3, R4, R5 = Open
Remove all jumpers from JP2
May 2008
5
8
8
5
NC
NC
NC
NC
7
2
4
GND
1
JP1
2
M9999-052908-A
Micrel, Inc.
MIC69101/03 Evaluation Board
Bill of Materials
Item
Part Number
C1
R1
R2
Description
Qty
10µF/6.3V, X5R, 0603 Ceramic Capacitor
1
4.7µF/6.3V, X7R, 0805 Ceramic Capacitor
1
(1)
C1608X5R106M
TDK
0603D106MAT2A
AVX(2)
GRM188R60J106ME47D
C2
Manufacturer
Murata
(3)
0805ZC475MAT2A
AVX(2)
GRM21BC71A475KA73L
Murata(3)
CRCW06031002FKEA
Vishay Dale(4)
10k, 1%, 0603 Resistor
1
CRCW06034K99FKEA
(4)
4.99k, 1%, 0603 Resistor
1
(4)
Vishay Dale
R3
CRCW06033K83FKEA
Vishay Dale
3.83k, 1%, 0603 Resistor
1
R4
CRCW06032K49FKEA
Vishay Dale(4)
2.49k, 1%, 0603 Resistor
1
CRCW06031K78FKEA
(4)
1.78k, 1%, 0603 Resistor
1
(4)
100k, 1%, 0603 Resistor
R5
R6
CRCW0603100KFKEA
U1
MIC69101YML
MIC69103YML
Vishay Dale
Vishay Dale
Micrel
(5)
Low VIN, Low VOUT 1A LDO Regulator
1
Notes:
1. TDK: www.tdk.com
2. AVX: www.avx.com
3. Murata: www.murata.com
4. Vishay Dale: www.vishay.com
5. Micrel: www.micrel.com
May 2008
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M9999-052908-A
Micrel, Inc.
MIC69101/03 Evaluation Board
PCB Layout Recommendations
Top Layer
Bottom Layer
May 2008
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M9999-052908-A
Micrel, Inc.
MIC69101/03 Evaluation Board
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.
© 2007 Micrel, Incorporated.
May 2008
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M9999-052908-A