Datasheet

ManualsBrandsLINEAR TECHNOLOGY ManualsPSU ComponentsDC/DC converter (SMD) 5 V 2 A No. of outputs: 1 x

LTM8023

8023fg

LOAD CURRENT (A)

0.01

EFFICIENCY (%)

POWER LOSS (W)

0.1 1 10

8023 TA01b

0.2

0.4

0.6

0.8

1.2

1.0

1.8

1.6

1.4

= 12V

OUT

= 3.3V

f = 650 kHz

FEATURES

APPLICATIONS

DESCRIPTION

2A, 36V DC/DC

Step-Down µModule

Regulator

The LTM

8023 is a complete 2A, DC/DC step-down power

supply. Included in the package are the switching controller,

power switches, inductor, and all support components.

Operating over an input voltage range of 3.6V to 36V, the

LTM8023 supports an output voltage range of 0.8V to 10V,

and a switching frequency range of 200kHz to 2.4MHz,

each set by a single resistor. Only the bulk input and output

ﬁ lter capacitors are needed to ﬁ nish the design.

The low proﬁ le package enables utilization of unused

space on the bottom of PC boards for high density point

of load regulation.

The LTM8023 is packaged in a thermally enhanced, compact

and low proﬁ le over-molded land grid array (LGA) and ball

grid array (BGA) packages suitable for automated assembly

by standard surface mount equipment. The LTM8023 is

RoHS compliant.

5.5V

to 36V

, 3.3V/2A DC/DC μModule

Converter

Complete Step-Down Switch Mode Power Supply

Wide Input Voltage Range: 3.6V to 36V

2A Output Current

0.8V to 10V Output Voltage

Selectable Switching Frequency: 200kHz to 2.4MHz

Current Mode Control

Programmable Soft-Start

Pb-Free RoHS Compliant Package

Gold Finish LGA (e4)

SAC305 BGA (e1)

Tiny, Low Proﬁ le, Surface Mount LGA (9mm ×

11.25mm × 2.82mm) and BGA (9mm × 11.25mm ×

3.42mm) Packages

Automotive Battery Regulation

Power for Portable Products

Distributed Supply Regulation

Industrial Supplies

Wall Transformer Regulation

Efﬁ ciency and Power Loss

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.

TYPICAL APPLICATION

OUT

RUN/SS

*RUNNING VOLTAGE RANGE. PLEASE

REFER TO APPLICATIONS INFORMATION

FOR START-UP DETAILS

PGOOD

BIAS

ADJ

LTM8023

154k49.9k

8023 TA01

OUT

3.3V

SYNC

5.5V TO 36V

SELECTABLE

OPERATING

FREQUENCY

2.2µF

AUX

GND

2.2µF

Summary of content (24 pages)

PAGE 1
LTM8023 2A, 36V DC/DC Step-Down µModule Regulator DESCRIPTION FEATURES n n n n n n n n n Complete Step-Down Switch Mode Power Supply Wide Input Voltage Range: 3.6V to 36V 2A Output Current 0.8V to 10V Output Voltage Selectable Switching Frequency: 200kHz to 2.4MHz Current Mode Control Programmable Soft-Start Pb-Free RoHS Compliant Package Gold Finish LGA (e4) SAC305 BGA (e1) Tiny, Low Proﬁle, Surface Mount LGA (9mm × 11.25mm × 2.82mm) and BGA (9mm × 11.25mm × 3.
PAGE 2
LTM8023 ABSOLUTE MAXIMUM RATINGS (Note 1) VIN, RUN/SS Voltage .................................................40V ADJ, RT, SHARE Voltage .............................................5V VOUT, AUX .................................................................10V PGOOD, SYNC ..........................................................30V BIAS ..........................................................................16V VIN + BIAS .................................................................
PAGE 3
LTM8023 ELECTRICAL CHARACTERISTICS The l denotes the speciﬁcations which apply over the full operating temperature range, otherwise speciﬁcations are at TA = 25°C. VIN = 10V, VRUN/SS = 10V, VBIAS = 3V, RT = 60.4k, COUT = 4.7μF unless otherwise speciﬁed. SYMBOL PARAMETER CONDITIONS MIN VIN Input DC Voltage VOUT Output DC Voltage 0A < IOUT ≤ 2A, RADJ Open, COUT = 51μF (Note 3) 0A < IOUT ≤ 2A, RADJ = 43.2k, COUT = 51μF (Note 3) l TYP 3.6 MAX 36 0.
PAGE 4
LTM8023 TYPICAL PERFORMANCE CHARACTERISTICS Efﬁciency (8VOUT) Efﬁciency (5VOUT) 100 Efﬁciency (3.3VOUT) 90 90 VOUT = 8V VOUT = 5V VOUT = 3.3V 85 85 80 80 80 70 60 50 40 EFFICIENCY (%) 90 EFFICIENCY (%) EFFICIENCY (%) TA = 25°C unless otherwise noted 75 70 65 60 12VIN 24VIN 36VIN 30 20 0.01 0.1 OUTPUT CURRENT (A) 70 65 60 12VIN 24VIN 36VIN 55 50 0.01 1 75 0.1 OUTPUT CURRENT (A) 8023 G01 5VIN 12VIN 24VIN 36VIN 55 50 0.01 1 0.
PAGE 5
LTM8023 TYPICAL PERFORMANCE CHARACTERISTICS Output Short-Circuit Current vs Input Voltage Maximum Load Current vs Input Voltage (8VOUT, LGA) BIAS Current vs Load Current 30 3200 3000 2500 25 2600 2400 2200 2000 LOAD CURRENT (mA) 2800 BIAS CURRENT (mA) OUTPUT CURRENT (mA) TA = 25°C unless otherwise noted 20 3.
PAGE 6
LTM8023 TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise noted 5VOUT Temperature Rise vs Load Current (BGA) 3.
PAGE 7
LTM8023 PIN FUNCTIONS VIN (Bank 1): The VIN pin supplies current to the LTM8023’s internal regulator and to the internal power switch. This pin must be locally bypassed with an external, low ESR capacitor of at least 2.2μF. VOUT (Bank 2): Power Output Pins. Apply the output ﬁlter capacitor and the output load between these pins and GND pins. AUX (Pin F5): Low Current Voltage Source for BIAS.
PAGE 8
LTM8023 BLOCK DIAGRAM VIN VOUT 4.7μH 0.1μF 4.
PAGE 9
LTM8023 OPERATION The LTM8023 is a standalone nonisolated step-down switching DC/DC power supply. It can deliver up to 2A of DC output current with only bulk external input and output capacitors. This module provides a precisely regulated output voltage programmable via one external resistor from 0.8VDC to 10VDC. The input voltage range is 3.6V to 36V. Given that the LTM8023 is a step-down converter, make sure that the input voltage is high enough to support the desired output voltage and load current.
PAGE 10
LTM8023 APPLICATIONS INFORMATION Table 1. Recommended Component Values and Conﬁguration (TA = 25°C) VIN VOUT CIN COUT RADJ BIAS fOPTIMAL (kHz) RT(OPTIMAL) fMAX (kHz) RT(MIN) 3.6V to 36V 0.82V 10μF 200μF 1206 13M ≥2.8V, <16V 250 150k 250 150k 3.6V to 36V 1.00V 10μF 147μF 1206 1.87M ≥2.8V, <16V 300 124k 300 124k 3.6V to 36V 1.20V 10μF 100μF 1206 953k ≥2.8V, <16V 350 105k 350 105k 3.6V to 36V 1.50V 10μF 100μF 1206 549k ≥2.8V, <16V 400 88.7k 400 88.7k 3.
PAGE 11
LTM8023 APPLICATIONS INFORMATION Ceramic capacitors are also piezoelectric. In Burst Mode operation, the LTM8023’s switching frequency depends on the load current, and can excite a ceramic capacitor at audio frequencies, generating audible noise. Since the LTM8023 operates at a lower current limit during Burst Mode operation, the noise is typically very quiet to a casual ear. If this audible noise is unacceptable, use a high performance electrolytic capacitor at the output.
PAGE 12
LTM8023 APPLICATIONS INFORMATION Load Sharing Minimum Input Voltage Two or more LTM8023’s may be paralleled to produce higher currents. To do this, tie the VIN, ADJ, VOUT and SHARE pins of all the paralleled LTM8023’s together. To ensure that paralleled modules start up together, the RUN/SS pins may be tied together, as well. If the RUN/SS pins are not tied together, make sure that the same valued soft-start capacitors are used for each module.
PAGE 13
LTM8023 APPLICATIONS INFORMATION Soft-Start Shorted Input Protection The RUN/SS pin can be used to soft-start the LTM8023, reducing the maximum input current during start-up. The RUN/SS pin is driven through an external RC ﬁlter to create a voltage ramp at this pin. Figure 3 shows the start-up and shutdown waveforms with the soft-start circuit. By choosing an appropriate RC time constant, the peak start-up current can be reduced to the current that is required to regulate the output, with no overshoot.
PAGE 14
LTM8023 APPLICATIONS INFORMATION PCB Layout Most of the headaches associated with PCB layout have been alleviated or even eliminated by the high level of integration of the LTM8023. The LTM8023 is nevertheless a switching power supply, and care must be taken to minimize EMI and ensure proper operation. Even with the high level of integration, you may fail to achieve speciﬁed operation with a haphazard or poor layout. See Figure 5 for a suggested layout. GND RT RUN/SS AUX BIAS CIN 6.
PAGE 15
LTM8023 APPLICATIONS INFORMATION CLOSING SWITCH SIMULATES HOT PLUG IIN VIN DANGER VIN 20V/DIV RINGING VIN MAY EXCEED ABSOLUTE MAXIMUM RATING LTM8023 + 4.7μF LOW IMPEDANCE ENERGIZED 24V SUPPLY IIN 10A/DIV STRAY INDUCTANCE DUE TO 6 FEET (2 METERS) OF TWISTED PAIR 20μs/DIV (6a) 0.7Ω LTM8023 VIN 20V/DIV + 0.1μF 4.7μF IIN 10A/DIV (6b) LTM8023 + 22μF 35V AI.EI. 20μs/DIV VIN 20V/DIV + 4.7μF IIN 10A/DIV (6c) 20μs/DIV 8023 F06 Figure 6.
PAGE 16
LTM8023 APPLICATIONS INFORMATION Thermal Considerations The LTM8023 output current may need to be derated if it is required to operate in a high ambient temperature or deliver a large amount of continuous power. The amount of current derating is dependent upon the input voltage, output power and ambient temperature. The temperature rise curves given in the Typical Performance Characteristics section can be used as a guide.
PAGE 17
LTM8023 APPLICATIONS INFORMATION A graphical representation of these thermal resistances is given in Figure 7. The blue resistances are contained within the μModule regulator, and the green are outside. The die temperature of the LTM8023 must be lower than the maximum rating of 125°C, so care should be taken in the layout of the circuit to ensure good heat sinking of the LTM8023. The bulk of the heat ﬂow out of the LTM8023 is through the bottom of the module and the LGA pads into the printed circuit board.
PAGE 18
LTM8023 TYPICAL APPLICATIONS 0.82V Step-Down Converter VIN* 3.6V TO 15V VIN 1.8V Step-Down Converter VOUT BIAS 10μF 200μF VOUT 0.82V 2A VIN* 3.6V TO 15V VIN VOUT BIAS 4.7μF RUN/SS 100μF RUN/SS AUX AUX LTM8023 LTM8023 SHARE PGOOD SHARE PGOOD ADJ ADJ RT GND SYNC RT GND SYNC 8023 TA02 105k 8023 TA03 13M 79k *RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS VIN 5V Step-Down Converter VOUT 47μF 2.2μF VOUT 2.5V 2A VIN* 7.
PAGE 19
LTM8023 TYPICAL APPLICATIONS –5V Positive to Negative Converter VIN* 7V TO 31V VIN –5V Positive to Negative Converter Load Current vs Input Voltage VOUT 2500 AUX RUN/SS BIAS LOAD CURRENT (mA) 2000 LTM8023 SHARE 2.2μF PGOOD 10μF ADJ RT 1500 1000 500 GND SYNC 8023 TA06 39.2k 93.1k 0 –5V 0 *RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS 10 20 30 INPUT VOLTAGE (V) 40 8023 TA06b Two LTM8023’s in Parallel, 3.3V at 4A VIN* 6.
PAGE 20
000 3.810 2.540 1.270 0.3175 0.3175 1.270 2.540 SUGGESTED PCB LAYOUT TOP VIEW 1.905 PACKAGE TOP VIEW 0.000 3.175 X 9.00 BSC Y aaa Z 2.45 – 2.55 DETAIL A MOLD CAP 0.27 – 0.37 SUBSTRATE DETAILS OF PAD #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE PAD #1 IDENTIFIER MAY BE EITHER A MOLD OR A MARKED FEATURE 4 SYMBOL TOLERANCE aaa 0.15 bbb 0.10 6. THE TOTAL NUMBER OF PADS: 50 5.
PAGE 21
0.630 ±0.025 Ø 50x E PACKAGE TOP VIEW 2.540 SUGGESTED PCB LAYOUT TOP VIEW 2.540 4 1.270 PIN “A1” CORNER 0.3175 0.000 0.3175 aaa Z 1.270 Y 4.445 3.175 1.905 0.635 0.000 0.635 1.905 3.175 4.445 D X 4.76 4.13 aaa Z NOM 3.42 0.60 2.82 0.78 0.63 11.25 9.0 1.27 8.89 7.62 0.32 2.50 DIMENSIONS b1 A A2 MAX 3.62 0.70 2.92 0.85 0.66 NOTES DETAIL B PACKAGE SIDE VIEW 0.37 2.55 0.15 0.10 0.20 0.30 0.15 TOTAL NUMBER OF BALLS: 50 0.27 2.45 MIN 3.22 0.50 2.72 0.71 0.
PAGE 22
LTM8023 PACKAGE DESCRIPTION Table 3.
PAGE 23
LTM8023 REVISION HISTORY (Revision history begins at Rev F) REV DATE DESCRIPTION PAGE NUMBER F 8/10 Added Note 5 3 G 8/11 Added BGA package. Changes reﬂected throughout the data sheet. 1 to 24 8023fg Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use.
PAGE 24
LTM8023 PACKAGE PHOTOGRAPHS LGA BGA RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTM8022 36V, 1A Step-Down μModule Regulator 0.8V ≤ VOUT ≤ 10V, Synchronizable, 9mm × 11.25mm × 2.8mm LGA LTM8025 36V, 3A Step-Down μModule Regulator 0.8V ≤ VOUT ≤ 24V, Synchronizable, 9mm × 15mm × 4.3mm LGA LTM8027 60V, 4A Step-Down μModule Regulator 2.5V ≤ VOUT ≤ 24V, Synchronizable, 15mm × 15mm × 4.3mm LGA LTM4612 EN55022B Certiﬁed 36V, 5A Step-Down μModule Regulator 3.