19-5771; Rev 1; 1/12
MAX16952 Evaluation Kit
Evaluates: MAX16952
General Description
The MAX16952 evaluation kit (EV kit) is a fully assem-
bled and tested PCB that contains all the components
necessary to evaluate the performance of the MAX16952
synchronous PWM step-down controller. The device is
available in a 16-pin TSSOP package and features an
exposed pad for enhanced thermal dissipation.
The EV kit requires a 6V to 36V power supply for normal
operation. The EV kit output is configured to 5V and can
deliver up to 5A output current. The EV kit can be easily
reconfigured to operate the controller in continuous PWM
mode, SKIP mode, or external synchronization operation.
The controller switching frequency is set to 2.2MHz. The
EV kit includes a jumper to enable the circuit and an LED
to monitor the power-good output.
S
6V to 36V Input Range
S
5V at Up to 5A Output
S
2.2MHz Switching Frequency
S
Selectable Forced Fixed-Frequency PWM Mode,
Features
SKIP Mode, or External Synchronization
S
Power-Good LED Indicator
S
Enable Input
S
Cycle-by-Cycle Current Limit and Thermal
Protection
S
Proven PCB Layout
S
Fully Assembled and Tested
Ordering Information
appears at end of data sheet.
Component List
DESIGNATION
BIAS, EN, FSYNC,
OUT (x2),
SUP (x2)
C1, C4
QTY
7
DESCRIPTION
Red multipurpose test points
0.1FF
Q10%,
50V X7R ceramic
capacitors (0603)
Murata GRM188R71H104K
47FF
Q20%,
50V electrolytic
capacitor (D8)
Panasonic EEE-FK1H470XP
Not installed, ceramic
capacitors (0603)
47FF
Q20%,
6.3V X7R ceramic
capacitors (1210)
Murata GRM32ER70J476M
2.2FF
Q10%,
10V X7R ceramic
capacitor (0603)
Murata GRM188R71A225K
3300pF
Q10%,
50V X7R
ceramic capacitor (0603)
Murata GRM188R71H332K
4.7FF
Q10%,
50V X7R ceramic
capacitors (1206)
Murata GRM31CR71H475K
60V, 3A Schottky diode (SMB)
Diodes Inc. B360B-13-F
Red LED (0603)
DESIGNATION
D3
JU1
JU2
L1
2
QTY
0
1
1
1
DESCRIPTION
Not installed, Schottky diode
(3 SOT23)
3-pin header
2-pin header
1.5FH, 18A inductor
Würth 7443330150
40V, 7.6A n-channel MOSFETs
(8 SO)
Fairchild FDS8449
Black multipurpose test points
Not installed, resistors (0603)
0.015I
Q1%,
1/2W resistor
(1206)
IRC LRF1206LF-01-R015-F
0I
Q5%
resistors (0603)
13.0kI
Q1%
resistor (0603)
30kI
Q5%
resistor (0603)
10kI
Q5%
resistor (0603)
51.1kI
Q1%
resistor (0603)
Synchronous buck converter
(16 TSSOP-EP)
Maxim MAX16952AUE/V+
Shunts
PCB: MAX16952 EVALUATION
KIT
C2
1
N1, N2
PGND (x5), SGND
R2, R5, R6
R4
R7, R12
R8
R9
R10
R11
U1
—
—
2
6
0
1
2
1
1
1
1
1
2
1
C5, C9
0
C6, C7
2
C8
1
C10
1
C11, C13
2
D1
D2
1
1
For pricing, delivery, and ordering information, please contact Maxim Direct at
1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
MAX16952 Evaluation Kit
Evaluates: MAX16952
Component Suppliers
SUPPLIER
Diodes Incorporated
Fairchild Semiconductor
IRC, Inc.
Murata Electronics North America, Inc.
Panasonic Corp.
Würth Electronik GmbH & Co. KG
PHONE
805-446-4800
888-522-5372
361-992-7900
770-436-1300
800-344-2112
201-785-8800
www.diodes.com
www.fairchildsemi.com
www.irctt.com
www.murata-northamerica.com
www.panasonic.com
www.we-online.com
WEBSITE
Note:
Indicate that you are using the MAX16952 when contacting these component suppliers.
Quick Start
• MAX16952 EV kit
• 12V, 1A power supply
• An electronic load capable of sinking 1A (e.g.,
HP6060B)
• Two digital voltmeters (DVMs)
The EV kit is fully assembled and tested. Follow the steps
below to verify board operation:
1) Verify that a shunt is installed across pins 2-3 on
jumper JU1.
2) Verify that a shunt is not installed across jumper JU2
(output enabled).
3) Connect the load across the OUT and PGND test
points.
4) Connect the first DVM across the SUP and PGND test
points.
5) Connect the second DVM across the OUT and PGND
test points.
6) Connect the power supply’s positive and ground ter-
minals to the SUP and PGND test points, respectively.
7) Turn on the power supply and set to 12V with a 1A
current limit.
8) Enable the 1A electronic load.
9) Verify that the red LED (D2) is off and the DVM at OUT
measures 5V.
Detailed Description of Hardware
The MAX16952 EV kit is a fully assembled and tested
PCB that contains all the components necessary to
evaluate the performance of the MAX16952 synchronous
PWM step-down controller. The device is available in a
16-pin TSSOP package and features an exposed pad for
thermal dissipation. The device has a 3.5V to 36V input
voltage range. The EV kit circuit is designed to operate
from a single 6V to 36V DC power supply.
The EV kit is configured to output 5V and provides up to
5A load current at the OUT and PGND test points. The
switching frequency is set to 2.2MHz using resistor R8.
The peak inductor current is set to 5.3A using resistor
R4. The EV kit can be configured to operate in forced
fixed-frequency PWM mode, low-quiescent current SKIP
mode, or external synchronization using jumper JU1. The
EV kit features test points to evaluate the enable (EN)
feature and to monitor the BIAS output voltage. A
red LED (D2) is available to monitor the power-good
(PGOOD) output signal.
Jumper JU1 configures the EV kit for external synchro-
nization, forced fixed-frequency PWM, or SKIP mode
operation. Install a shunt across pins 1-2 on JU1 to
operate the EV kit in forced fixed-frequency PWM mode.
Place a shunt across pins 2-3 on JU1 to operate in SKIP
mode. Remove the shunt on JU1 when synchronizing,
using an external digital clock signal at the FSYNC and
SGND test points. Refer to the
Forced Fixed-Frequency
PWM Mode
and
Light-Load Low-Quiescent Operating
(SKIP) Mode
sections in the MAX16952 IC data sheet for
additional information. See Table 1 for JU1 configuration.
Required Equipment
Procedure
Modes of Operation (JU1)
Maxim Integrated
2
MAX16952 Evaluation Kit
Evaluates: MAX16952
Table 1. Jumper Descriptions (JU1, JU2)
JUMPER
SHUNT POSITION
1-2
2-3*
JU1
Open
Closed
Open*
DESCRIPTION
Connects FSYNC to V
BIAS
to enable continuous PWM mode.
Connects FSYNC to AGND to enable SKIP mode under light-load conditions.
When FSYNC is unconnected or when a clock source is present, continuous PWM mode is
enabled. FSYNC can be used to synchronize with other supplies when a clock source is
present.
Connects EN to AGND (shutdown).
Connects EN to V
SUP
through a pullup resistor (normal operation).
JU2
*Default
position.
For external synchronization, apply a digital signal at the
FSYNC and SGND test points with a frequency between
1MHz and 2.42MHz. For proper frequency synchroniza-
tion, FSYNC’s input frequency must be at least 110% of
the EV kit’s programmed internal oscillator frequency.
When FSYNC is driven with an external digital clock, the
device synchronizes to the rising edge of the external
clock. The digital square-wave clock source at FSYNC
must provide the following signal qualities:
• 0 to 0.4V logic-low
• 1.4V to 5.5V logic-high
• 1MHz to 2.42MHz input frequency
• 100ns minimum pulse width
The EV kit output is enabled through pullup resistor R11
when the power source applied between the SUP and
PGND test points is greater than 1.8V. To enable the EV
kit output, remove the shunt on jumper JU2. To disable
the EV kit output, install a shunt on JU2. See Table 2 for
JU2 configuration. If the EN pin is toggled from low to
high, the switching regulator shuts down and remains
off until the output voltage decays to 1.25V. At that point,
the EV kit output turns on using the soft-start sequence.
The controller’s approximate switching frequency is
set to 2.2MHz by resistor R8. Replace R8 with a new
resistor value to set the switching frequency between
1MHz and 2.2MHz. Refer to the
Setting the Switching
Frequency
section in the MAX16952 IC data sheet for
selecting R8 when reconfiguring the EV kit switching
frequency. When reconfiguring the EV kit switching
frequency, it is necessary to replace the compensation
network components C9, C10, R9, and power com-
ponents. Refer to the
Design Procedure
section in the
MAX16952 IC data sheet for computing new compensa-
tion and power component values.
The EV kit step-down controller’s output voltage (OUT) is
configured to 5V. OUT can be reconfigured between 1V
and 10V by removing resistor R7 and inserting feedback
resistors at the R5 and R6 (0603) PCB pads. To configure
the EV kit’s output voltage, refer to the
Setting the Output
Voltage
section in the MAX16952 IC data sheet for
instructions on selecting resistor values. Also refer to the
Effective Input-Voltage Range
and
Output Capacitor
sec-
tions in the MAX16952 IC data sheet. Refer to the
Design
Procedure
section in the MAX16952 IC data sheet and
modify the compensation network accordingly.
The EV kit provides a red LED power-good indicator (D2)
to monitor undervoltage and overvoltage conditions at
OUT. D2 illuminates when OUT falls below 90% (typ) or
rises above 111% (typ) of its nominal regulated voltage.
The device’s current-limit circuit uses differential current-
sense inputs (CS and OUT) to limit the peak inductor
current. The EV kit peak inductor current is set to 5.3A
using resistor R4. Use the following equation to calculate
the resistance needed to reconfigure the inductor peak
current limit:
R4
=
80mV
I
ILIM
Configuring the Output Voltage (OUT)
Enable Control (JU2)
Power-Good Indicator (D2)
Peak Inductor Current Limit
Switching Frequency
where R4 is in milliohms and I
ILIM
is the peak inductor
current in amps.
Maxim Integrated
3
MAX16952 Evaluation Kit
Evaluates: MAX16952
Figure 1. MAX16952 EV Kit Schematic
Maxim Integrated
4
MAX16952 Evaluation Kit
Evaluates: MAX16952
1.0”
1.0”
Figure 2. MAX16952 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX16952 EV Kit PCB Layout—Component Side
1.0”
Figure 4. MAX16952 EV Kit PCB Layout—VCC Layer 2
Maxim Integrated
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