Linear LTM4636 User Manual

DESCRIPTION

DEMO MANUAL DC2230A-A

LTM4636

40A DC/DC µModule Regulator

Demonstration circuit 2230A-A features the LTM®4636EY,
a 40A high efficiency, switch mode step-down power
µModule
15V. For input voltage range from 4.7V to 5.5V, short PV
pin to V
output voltage range is 0.6V to 3.3V. Derating is necessary
for certain V
board operates in continuous conduction mode in heavy
load conditions. For high efficiency at low load currents,
the MODE_PLLIN jumper selects pulse-skipping mode for
noise sensitive applications or BurstMode
less noise sensitive applications. The MODE_PLLIN pin

®

regulator. The input voltage range is from 4.7V to

pin with R8 = R21 = 0Ω and remove R17. The

IN

, V

IN

, frequency and thermal conditions. The

OUT

®

operation in

CC

BOARD PHOTO

also allows the LTM4636 to synchronize to an external
clock signal. DC2230A-A has the option of choosing both
internal and external compensation circuit for LTM4636.
Tying the PHASMD pin to different voltage generates cer
tain phase difference between MODE_PLLIN and CLKOUT.
The LTM4636
this demo manual prior to working on or modifying demo
circuit DC2230A-A.

Design files for this circuit board are available at

http://www.linear.com/demo/DC2230A-A

L, LT, LTC, LTM, Linear Technology, the Linear logo, Burst Mode and μModule are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.

data sheet must be read in conjunction with

-

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DEMO MANUAL DC2230A-A

PERFORMANCE SUMMARY

PARAMETER CONDITIONS/NOTES VALUE

Input Voltage Range 4.7V to 15V

Output Voltages 1.0V ± 1.3%

Maximum Continuous Output Current Derating is Necessary for Certain Operating Conditions. See Data Sheet for Details. 40ADC

Operating Frequency 350kHz

Efficiency V

Load Transient V

= 12V, V

IN

= 12V, V

IN

= 1.0V, I

OUT

= 1.0V, I

OUT

= 40A 87.7% (see Figure 2)

OUT

= 0A to 10A 81mV (see Figure 3)

STEP

QUICK START PROCEDURE

Vary the input voltage from 6V to 15V and adjust the

Demonstration circuit 2230A-A is an easy way to evalu­ate the performance of the LTM4636EY. Please refer to
Figure1

for proper measurement equipment setup and

follow the procedure below.

4.
load current from 0A – 40A. Observe the output volt­age regulation, ripple voltage, efficiency, and other
parameters.

1. Place jumpers in the following positions for a typical
application:

MODE RUN

CCM ON

2. With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A
and V

supply to 12V.

IN

3. Turn on the power supply at the input. The output volt­age should be 1.0V ± 1.3% (0.987V to 1.013V).

(Optional) For optional load transient test, apply an

5.
adjustable pulse signal between IOSTEP_CLK and GND
test points. The pulse amplitude sets the load step cur
rent amplitude. Keep the pulse width short (<1ms) and

<

pulse duty cycle low (

5%) to limit the thermal stress

on the load transient circuit.

6. (Optional) LTM4636 can be synchronized to an external
clock signal. Place the JP1 jumper on EXT_CLK and
apply a clock signal (0V to 5V, square wave) on the
MODE_PLLIN test point.

-

2

dc2230aaf

+

–

+

–

+

–

QUICK START PROCEDURE

DEMO MANUAL DC2230A-A

LOAD

+

–

Figure 1. Measurement Setup of DC2230A-A

dc2330aaf

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