MAX1729EVKIT

MAX1729EVKIT Datasheet

MAX1729 Evaluation Kit

Part	Datasheet
MAX1729EVKIT	MAX1729EVKIT (pdf)

PDF Datasheet Preview
MAX1729 Evaluation Kit Evaluates MAX1729 The MAX1729 evaluation kit EV kit is a low-power, step-up DC-DC converter followed by a low-dropout linear regulator. It accepts a positive input voltage between 2.7V to 5.5V and converts it to an output voltage ranging from 2.5V to 16V. The output voltage is dynamically adjustable through an external 3kHz to 12kHz pulse-width-modulated PWM control signal. An on-chip temperature sensor provides compensation for display temperature characteristics. This makes the MAX1729 ideally suited for electrically controlled birefringence ECB and LCD bias-supply generation o High-Accuracy Reference Voltage ±1% o On-Chip Temperature-Sensor Output o 2.7V to 5.5V Input Range o Dynamic Control of Output Voltage o 0.4µA Typical Shutdown Current o 10-Pin µMAX Package o Surface-Mount Construction o Fully Assembled and Tested Component List DESIGNATION QTY C1, C6 DESCRIPTION 0.1µF ceramic capacitors Not installed 0.068µF ceramic capacitor C4, C7 1µF ceramic capacitors Taiyo Yuden TMK316BJ105KL 1 1000pF ceramic capacitor 1 3-pin jumper 220µH inductor Murata LQH3C221K34 0 Not installed 1 MAX1729EUB SUPPLIER Murata Taiyo Yuden Component Suppliers PHONE 814-237-1431 408-573-4150 FAX 814-238-0490 408-573-4159 PART MAX1729EVKIT Ordering Information TEMP. RANGE 0°C to +70°C IC PACKAGE 10µMAX Quick Start The MAX1729 EV kit is a fully assembled and tested surface-mount board. Follow the steps below to verify board operation. Do not turn on the power supply until all connections are completed. 1 Connect a 2.7V to 5.5V supply to the pads marked VIN and GND. 2 Connect a voltmeter and load, if any, to the VOUT pad. 3 Place the shunt on JU1 across pins 2 and 4 Turn on the power and verify that the output voltage is approximately 16.35V. 5 For other output voltages, refer to the Output Voltage Control section. Detailed Description Jumper Selection Jumper JU1, in the 2-3 position, connects CTLIN to VIN. This places the output voltage at maximum and is equivalent to applying a PWM signal with a 100% duty cycle. In the 1-2 position, CTLIN is connected to GND. This places the MAX1729 into shutdown mode and is equivalent to applying a PWM signal with a 0% duty cycle. When applying a PWM signal to the CTLIN pad, the shunt must be removed from jumper JU1. Maxim Integrated Products 1 For free samples & the latest literature or phone For small orders, phone MAX1729 Evaluation Kit Evaluates MAX1729 Table Jumper JU1 Functions JUMPER JUMPER POSITION FUNCTION CTLIN = high, MAX1729 enabled. Output voltage at maximum value. CTLIN = low, MAX1729 in shutdown mode. Open Drive CTLIN pad with external PWM signal. Output Voltage Control The output voltage of the MAX1729 EV kit is dynamically adjustable through a 3kHz to 12kHz PWM control signal applied to the CTLIN pad. The output is adjustable from 2.5V to 16V in internal feedback mode or from 2.5V to 18V in external feedback mode. The EV kit is initially set up for internal feedback operation. To use the EV kit for external feedback operation, cut the traces across R2 and R4 and insert resistors Refer to the MAX1729 data sheet to determine the resistor values. Temperature Compensation The MAX1729 EV kit includes a TC pad, which is a temperature-sensor output. This pad is used to compensate for ECB color or LCD contrast variations caused by changes in temperature. In internal feedback mode, this output is read by an external ADC and used to adjust the duty cycle of the PWM control signal. In external feedback mode, this output is summed directly into the feedback-resistor network. Refer to the MAX1729 data sheet to determine feedback-resistor values. L1 220µH VIN GND CTLIN C2 OPEN VIN 3 2 JU1 1 1 IN C1 0.1µF 10 GND 3 REF C6 0.1µF CTLIN 6 U1 MAX1729 LX 9 PS 8 C3 0.068µF OUT 7

PDF Datasheet Preview

MAX1729 Evaluation Kit

Evaluates MAX1729

The MAX1729 evaluation kit EV kit is a low-power, step-up DC-DC converter followed by a low-dropout linear regulator. It accepts a positive input voltage between 2.7V to 5.5V and converts it to an output voltage ranging from 2.5V to 16V. The output voltage is dynamically adjustable through an external 3kHz to 12kHz pulse-width-modulated PWM control signal. An on-chip temperature sensor provides compensation for display temperature characteristics. This makes the MAX1729 ideally suited for electrically controlled birefringence ECB and LCD bias-supply generation
o High-Accuracy Reference Voltage ±1% o On-Chip Temperature-Sensor Output o 2.7V to 5.5V Input Range o Dynamic Control of Output Voltage o 0.4µA Typical Shutdown Current o 10-Pin µMAX Package o Surface-Mount Construction o Fully Assembled and Tested

Component List

DESIGNATION QTY

C1, C6

DESCRIPTION 0.1µF ceramic capacitors Not installed 0.068µF ceramic capacitor

C4, C7
1µF ceramic capacitors Taiyo Yuden TMK316BJ105KL
1 1000pF ceramic capacitor
1 3-pin jumper
220µH inductor Murata LQH3C221K34
0 Not installed 1 MAX1729EUB

SUPPLIER Murata Taiyo Yuden

Component Suppliers

PHONE 814-237-1431 408-573-4150

FAX 814-238-0490 408-573-4159

PART MAX1729EVKIT
Ordering Information

TEMP. RANGE 0°C to +70°C

IC PACKAGE 10µMAX

Quick Start

The MAX1729 EV kit is a fully assembled and tested surface-mount board. Follow the steps below to verify board operation. Do not turn on the power supply until all connections are completed.
1 Connect a 2.7V to 5.5V supply to the pads marked VIN and GND.
2 Connect a voltmeter and load, if any, to the VOUT pad.
3 Place the shunt on JU1 across pins 2 and
4 Turn on the power and verify that the output voltage is approximately 16.35V.
5 For other output voltages, refer to the Output Voltage Control section.

Detailed Description

Jumper Selection Jumper JU1, in the 2-3 position, connects CTLIN to VIN. This places the output voltage at maximum and is equivalent to applying a PWM signal with a 100% duty cycle.

In the 1-2 position, CTLIN is connected to GND. This places the MAX1729 into shutdown mode and is equivalent to applying a PWM signal with a 0% duty cycle.

When applying a PWM signal to the CTLIN pad, the shunt must be removed from jumper JU1.

Maxim Integrated Products 1

For free samples & the latest literature or phone For small orders, phone

MAX1729 Evaluation Kit

Evaluates MAX1729

Table Jumper JU1 Functions

JUMPER

JUMPER POSITION

FUNCTION

CTLIN = high, MAX1729 enabled. Output voltage at maximum value.

CTLIN = low, MAX1729 in shutdown mode.

Open

Drive CTLIN pad with external PWM signal.

Output Voltage Control The output voltage of the MAX1729 EV kit is dynamically adjustable through a 3kHz to 12kHz PWM control signal applied to the CTLIN pad. The output is adjustable from 2.5V to 16V in internal feedback mode or from 2.5V to 18V in external feedback mode.

The EV kit is initially set up for internal feedback operation. To use the EV kit for external feedback operation, cut the traces across R2 and R4 and insert resistors Refer to the MAX1729 data sheet to determine the resistor values.

Temperature Compensation The MAX1729 EV kit includes a TC pad, which is a temperature-sensor output. This pad is used to compensate for ECB color or LCD contrast variations caused by changes in temperature. In internal feedback mode, this output is read by an external ADC and used to adjust the duty cycle of the PWM control signal. In external feedback mode, this output is summed directly into the feedback-resistor network. Refer to the MAX1729 data sheet to determine feedback-resistor values.

L1 220µH

VIN GND CTLIN

C2 OPEN

VIN 3 2 JU1 1
1 IN C1 0.1µF
10 GND
3 REF C6 0.1µF

CTLIN 6

U1 MAX1729

LX 9 PS 8

C3 0.068µF

OUT 7

Notice: we do not provide any warranties that information, datasheets, application notes, circuit diagrams, or software stored on this website are up-to-date or error free. The archived MAX1729EVKIT Datasheet file may be downloaded here without warranties.

Datasheet ID: MAX1729EVKIT 647260