MAXIM MAX8561EVKIT

19-2982; Rev 0; 9/03
MAX8561 Evaluation Kit
Features
♦ 2.7V to 5.5V Input Voltage Range
♦ 0.6V to 2.5V Adjustable Output Voltage Range
♦ VOUT1 = 1.8V/1.5V at 500mA (MAX8561)
♦ VOUT2 = 1.2V at 400mA or Bypass Mode
(MAX8562)
♦ 2MHz PWM Switching Frequency (MAX8561)
♦ 4MHz PWM Switching Frequency (MAX8562)
♦ 0.1µA (typ) Shutdown Current
♦ Surface-Mount Construction
Ordering Information
PART
TEMP RANGE
MAX8561EVKIT
0°C to +70°C
♦ Fully Assembled and Tested
IC PACKAGE
8 Thin DFN (3mm x 3mm)
Component List
DESIGNATION
C1, C4
C2, C5
C3
C6
QTY
DESCRIPTION
2
4.7µF ±10%, 6.3V X5R ceramic
capacitors (0603)
TDK C1608X5R0J475K
2
2.2µF ±10%, 6.3V X5R ceramic
capacitors (0603)
Taiyo Yuden JMK107BJ225KA or
TDK C1608X5R0J225K
DESIGNATION
QTY
DESCRIPTION
L2
1
1.0µH inductor (0806)
Taiyo Yuden LB2016B1R0M
P1
1
P-channel MOSFET (SC70)
Vishay Si1417EDH (top mark BB)
R1
1
150kΩ ±1% resistor (0603)
R2
1
301kΩ ±1% resistor (0603)
3
100kΩ ±1% resistors (0603)
1
150pF ±5%, 50V C0G ceramic
capacitor (0603)
TDK C1608C0G1H151JT or
equivalent
R3, R4, R5
U1
1
MAX8561ETA (8-pin thin DFN 3mm x
3mm) top mark AHD
U2
1
MAX8562ETA (8-pin thin DFN 3mm x
3mm) top mark AHE
1
100pF ±5%, 50V C0G ceramic
capacitor (0603)
TDK C1608C0G1H101JT or
equivalent
U3
0
Not installed
None
4
Shunts
None
1
MAX8561/MAX8562 PC board
JU1–JU4
4
3-pin headers
L1
1
2.2µH inductor
Murata LQH32CN2R2M51
Component Suppliers
PHONE
FAX
Murata
SUPPLIER
770-436-1300
770-436-3030
www.murata.com
WEBSITE
Taiyo Yuden
800-348-2496
847-925-0899
www.t-yuden.com
TDK
847-803-6100
847-390-4405
www.component.tdk.com
Vishay
203-268-6261
203-452-5670
www.vishay.com
Note: Please indicate that you are using the MAX8561/MAX8562 when contacting these component suppliers.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
Evaluates: MAX8561/MAX8562
General Description
The MAX8561 evaluation kit (EV kit) demonstrates the
MAX8561/MAX8562s’ up to 4MHz pulse-width modulated (PWM) step-down DC-DC converters. The two circuits
are optimized for powering the DSP/microprocessor or
the power amplifiers (PAs) in wireless applications. The
MAX8561 circuit provides two adjustable output voltages
in the 0.6V to 2.5V range from a 2.7V to 5.5V input, and
can deliver 500mA of load current. In comparison, the
MAX8562 circuit provides an adjustable voltage in the
0.6V to 2.5V range and a bypass mode where the output
voltage is shorted to the input by an external MOSFET.
Evaluates: MAX8561/MAX8562
MAX8561 Evaluation Kit
Quick Start
The MAX8561 EV kit is a fully assembled and tested
surface-mount board. Follow the steps below for board
operation. Do not turn on the power supply until all
connections are completed:
1) Verify that a shunt is connected across pins 1 and 2
of jumper JU1/JU3 (output enabled).
2) Verify that a shunt is connected across pins 2 and 3
of jumper JU2/JU4.
3) Connect a voltmeter across the VOUT1/VOUT2 and
the GND1/GND2 pads to monitor the output
voltage(s).
4) Connect a 2.7V to 5.5V power supply to the
BATT1/BATT2 pad. Connect the power-supply
ground terminal to the GND1/GND2 pad.
5) Turn on the power supply and verify that VOUT1 =
1.5V/VOUT2 = 1.2V.
Detailed Description
The MAX8561 EV kit circuit board demonstrates both the
MAX8561 (upper circuit) and the MAX8562 (lower circuit). The MAX8561 circuit is optimized for DSP or microprocessor application, and its switching frequency is set
at approximately 2MHz. The MAX8562 circuit is optimized to power the PA in wireless applications, and its
switching frequency is set to 4MHz. The EV kit requires a
power supply in the 2.7V to 5.5V range. The EV kit board
features jumpers that enable the user to configure the
shutdown mode and open-drain output control.
Shutdown Mode
The EV kit contains jumpers JU1 and JU3 to allow the
user to switch the MAX8561 and MAX8562 converters
from enable to shutdown mode. Shutdown mode reduces
the supply current to 0.1µA (typ) and sets the output voltage to 0V. See Table 1 for JU1 and JU3 configurations.
2
Open-Drain Control
Jumper JU2 allows the user to set VOUT1 at either 1.8V
or 1.5V. Jumper JU4 allows the user to enable the converter to regulate at 1.2V or set the output voltage VOUT2
to equal the input voltage BATT2 under the bypass
mode. See Table 2 for JU2 and JU4 configurations.
Evaluating Other Voltage Outputs
The MAX8561 EV kit circuit board comes with two independent circuits, the MAX8561 (upper circuit) and the
MAX8562 (lower circuit). The MAX8561 circuit can provide two adjustable output voltages, and the EV kit
default voltages of VOUT1 are set at 1.8V and 1.5V. To
evaluate other voltages at VOUT1, use 150kΩ at R1, and
calculate R2 and R3 using the following two equations:
R3 =
R2 =
R1VFB
VOUT(LOW ) − VFB
R1
VOUT(HIGH)
VFB
−
and
R1
−1
R3
where VFB = 0.6V and VOUT1(HIGH) and VOUT1(LOW)
are the two desired output voltages.
The EV kit default output voltage of VOUT2 is set at
1.2V. To evaluate other voltage outputs on the MAX8562
circuit, keep R4 as 100kΩ. Then R5 is given by:
R5 =
R4 VFB
VOUT2 − VFB
where VFB = 0.6V and VOUT2 is the desired output
voltage.
_______________________________________________________________________________________
MAX8561 Evaluation Kit
SHDN PIN
JU1/JU3 SHUNT LOCATION
MAX8561/MAX8562 OUTPUT
Pins 1 and 2
Connected to BATT_
Output enabled
Pins 2 and 3
Connected to GND
Output disabled
Connected to SHDN pad
Output controlled by the user (user-supplied control signal must be
connected to SHDN pad)
None
Table 2. Jumpers JU2 and JU4 Functions (ODI1/ODI2)
JU2/JU4 SHUNT
LOCATION
ODI1/ODI2 PIN
MAX8561 OUTPUT
MAX8562 OUTPUT
Pins 1 and 2
Connected to VIN
Pins 2 and 3
Connected to GND
VOUT1 = 1.5V
VOUT2 = 1.2V
Connected to
ODI1/ODI2 pad
Output controlled by the user (usersupplied control signal must be
connected to ODI1 pad)
Output controlled by the user (usersupplied control signal must be
connected to ODI2 pad)
None
VOUT1 = 1.8V
VOUT2 = BATT2
Table 3. Recommended R2 and R3 Values for Typical Dynamic Output Voltages
MAX8561 OUTPUTS
R2 VALUE (kΩ)
R3 VALUE (kΩ)
1.3
226
301
1.1
1.3
432
182
0.9
1.5
150
301
1.1
1.5
221
182
1.2
1.5
301
150
VOUT1LOW (V)
VOUT1HIGH (V)
0.9
Note: R1 = 150kΩ, L1 = 2.2µH, and C3 = 150pF.
_______________________________________________________________________________________
3
Evaluates: MAX8561/MAX8562
Table 1. Jumpers JU1 and JU3 Functions (SHDN)
Evaluates: MAX8561/MAX8562
MAX8561 Evaluation Kit
BATT1
1
C1
4.7µF
6.3V
GND1
LX
IN
R1
150kΩ
1%
U1
7
AGND
MAX8561
FB
JU1
1
3
ODI1
8
SHDN
1
2
4
ODI
3
BATT2
ODO
5
1
PGND
2
IN
ODO
5
U2
7
JU3
1
3
ODI2
4
3
P1
C4
4.7µF
6.3V
AGND
MAX8562
LX
L2
1µH
3
BATT2
SHDN2
R3
100kΩ
1%
BATT1
JU2
GND2
C3
150pF
R2
301kΩ
1%
2
C2
2.2µF
6.3V
6
BATT1
SHDN1
VOUT1
1.8V/1.5V AT 500mA
L1
2.2µH
3
R4
100kΩ
1%
8
2
SHDN
FB
1
3
2
5
1
2
VOUT2
1.2V AT 400mA/BATT2
C5
2.2µF
6.3V
6
R5
100kΩ
1%
BATT2
JU4
C6
100pF
6
4
ODI
PGND
2
Figure 1. MAX8561 EV Kit Schematic
4
_______________________________________________________________________________________
MAX8561 Evaluation Kit
Evaluates: MAX8561/MAX8562
Figure 2. MAX8561 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX8561 EV Kit PC Board Layout—Component Side
_______________________________________________________________________________________
5
Evaluates: MAX8561/MAX8562
MAX8561 Evaluation Kit
Figure 4. MAX8561 EV Kit PC Board Layout—Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
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