loading

RT5707 Ultra-Low Quiescent Current HCOT Buck Converter Evaluation Board

EVB_RT5707WSC

Share
ACTIVE

The RT5707 is a high efficiency synchronous step-down converter featuring typ. 360nA quiescent current. This document explains the function and use of the RT5707 evaluation board (EVB), and provides information to related setting of the evaluation board.

General Description

The RT5707 is a high efficiency synchronous step-down converter featuring typ. 360nA quiescent current. This document explains the function and use of the RT5707 evaluation board (EVB), and provides information to related setting of the evaluation board.



Performance Specification Summary

Summary of the RT5707 Evaluation Board performance specificiaiton is provided in Table 1. The ambient temperature is 25°C.


Table 1. RT5707 Evaluation Board Performance Specification Summary

Specification

Test Conditions

Min

Typ

Max

Unit

Input Voltage Range

2.2

--

5.5

V

Output Current

0

--

0.6

A

IQ_Non-SW

VOUT = 1.8V, IOUT = 0A, EN = VIN,

non-switching

--

360

800

nA

IQSW

VOUT = 1.8V, IOUT = 0A, EN = VIN, switching

--

460

1200

nA

Operation Frequency

VOUT = 1.8V, CCM mode

--

1.2

--

MHz

Line Regulation

VOUT = 1.8V, IOUT = 100mA, VIN = 2.2V to 5.5V

--

0.1

--

%/V

Load Regulation (VOUT_LoadReg1)

VOUT = 1.8V, including PFM operation

--

0.001

--

%/mA

Load Regulation

(VOUT_LoadReg2)

VOUT = 1.8V, only CCM operation

--

0.0005

--



Power-up Procedure

Suggestion Required Equipments

  • RT5707 Evaluation Board
  • DC power supply capable of at least 5.5V and 3A
  • Electronic load capable of 2A
  • Function Generator
  • Oscilloscope

Quick Start Procedures

The Evaluation Board is fully assembled and tested. Follow the steps below to verify board operation. Do not turn on supplies until all connections are made. When measuring the output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the output voltage ripple by touching the probe tip and ground ring directly across the last output capacitor.


Proper measurement equipment setup and follow the procedure below.

1) With power off, connect the input power supply to VIN and GND pins.

2) With power off, connect the electronic load between the VOUT and nearest GND pins.

3) Put jumper connectors on JP5 (VSEL1)/JP4 (VSEL2)/JP6 (VSEL3) to select VOUT value.


Table 2. Output Voltage Setting

Device

VOUT (V)

VSEL3

VSEL2

VSEL1

RT5707

1.2

0

0

0

1.5

0

0

1

1.8

0

1

0

2.1*

0

1

1

2.5

1

0

0

2.8

1

0

1

3

1

1

0

3.3*

1

1

1


4) Turn on the power supply at the input. Make sure that the input voltage does not exceeds 5.5V on the Evaluation Board.

5) Put jumper connectors on JP3 (EN Pull high).

6) Check for the proper output voltage using a voltmeter.

7) Once the proper output voltage is established, adjust the load within the operating ranges and observe the output voltage regulation, ripple voltage, efficiency and other performance.



Detailed Description of Hardware

Headers Description and Placement

一張含有 文字, 電路, 電子產品, 電子工程 的圖片

自動產生的描述

Carefully inspect all the components used in the EVB according to the following Bill of Materials table, and then make sure all the components are undamaged and correctly installed. If there is any missing or damaged component, which may occur during transportation, please contact our distributors or e-mail us at evb_service@richtek.com.


Test Points

The EVB is provided with the test points and pin names listed in the table below.

Test Point/

Pin Name

Function

VIN

Input voltage.

VOUT

Output voltage.

GND

Ground.

EN

Enable test point.

VSEL1

Output Voltage Select 1

VSEL2

Output Voltage Select 2

VSEL3

Output Voltage Select 3



Bill of Materials

Reference

Count

Part Number

Value

Description

Package

Manufacturer

U1

1

RT5707WSC

RT5707WSC

Step-Down Converter

WL-CSP-8B 0.9x1.6 (BSC)

RICHTEK

C1, C3

2

GRM155R60J106ME15

10µF

Capacitor, Ceramic

6.3V/X5R

0402

Murata

L1

1

1239AS-H-2R2M

2.2µH

Power Inductors

2520

Murata



Typical Applications

EVB Schematic Diagram

Technical Document Image Preview

1. The capacitance values of the input and output capacitors will influence the input and output voltage ripple.

2. MLCC capacitors have degrading capacitance at DC bias voltage, and especially smaller size MLCC capacitors will have much lower capacitance.


Measure Result

Output Ripple Measurement

Load Transient Response

Technical Document Image Preview

Technical Document Image Preview

Power On from EN

100% Duty Cycle

Technical Document Image Preview

Technical Document Image Preview

Quiescent Current

Shutdown Current

Technical Document Image Preview

Technical Document Image Preview

Efficiency vs. Output Current

Switching Frequency vs. Load Current

Technical Document Image Preview

Technical Document Image Preview


Note: When measuring the input or output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the output voltage ripple by touching the probe tip directly across the output capacitor.



Evaluation Board Layout

Figure 1 to Figure 2 are RT5707 Evaluation Board layout. This board size is 35mm x 35mm and is constructed on two-layer PCB.

一張含有 文字, 螢幕擷取畫面, 圓形, 字型 的圖片

自動產生的描述

Figure 1. Top View (1st layer)


一張含有 螢幕擷取畫面, 圓形, 文字, 設計 的圖片

自動產生的描述

Figure 2. Bottom View (2nd Layer)

Title Last Update Share Download
Evaluation Board User Guide 2023/11/03
Bill of Materials 2023/11/03
Schematic 2023/11/03
Gerber File 2023/11/03
RT5707/RT5707A
RT5707/RT5707A

The RT5707/A is a high efficiency synchronous step-down converter featuring typ. 360nA quiescent current. It provides high efficiency at light load down to 10mA. Its input voltage range is from 2.2V to 5.5V. The RT5707 provides eight programmable output voltage 1.2V to 3.3V while delivering output current up to 600mA, peak to 1A. The RT5707A provides eight programmable output voltage 0.7V to 3.1V while delivering output current up to 400mA, peak to 0.5A.

The Hysteretic Constant-On-Time (HCOT) operation with internal compensation allow the transient response to be optimized over a wide range of loads and output capacitors.

The RT5707/A is a available in WL-CSP-8B 0.9x1.6 (BSC) package.

Part NumberDistributorStockBuy From Authorized Distributor
EVB_RT5707WSC Digikey 6 Buy
Mouser 0 Lead-Time: 14 weeks
IC
Part NumberPackage TypePackage Qty.Free SampleDistributorStockBuy From Authorized Distributor
RT5707WSCWL-CSP0.9x1.6-8(BSC)3,000 Request Digikey 771 Buy
Mouser 0 Lead-Time: 14 weeks
TOP