Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - DC/DC voltage regulator Holder TQFN 16

General Description

The MAX5090A/B/C easy-to-use, high-efficiency, high-

voltage step-down DC-DC converters operate from an input

voltage up to 76V, and consume only 310µA quiescent

current at no load. This pulse-width-modulated (PWM)

converter operates at a fixed 127kHz switching frequency at

heavy loads, and automatically switches to pulse-skipping

mode to provide low quiescent current and high efficiency

at light loads. The MAX5090 includes internal frequency

compensation simplifying circuit implementation. The

device can also be synchronized with external system clock

frequency in a noise-sensitive application. The MAX5090

uses an internal low on-resistance and a high-voltage DMOS

transistor to obtain high efficiency and reduce overall system

cost. This device includes undervoltage lockout, cycle-

by-cycle current limit, hiccup-mode output short-circuit

protection, and overtemperature shutdown.

The MAX5090 delivers up to 2A output current. External

shutdown is included, featuring 19µA (typ) shutdown

current. The MAX5090A/MAX5090B versions have fixed

output voltages of 3.3V and 5V, respectively, while the

MAX5090C features an adjustable 1.265V to 11V output

voltage.

The MAX5090 is available in a space-saving 16-pin

thin QFN package (5mm x 5mm) and operates over the

automotive temperature range (-40°C to +125°C).

Applications

● Industrial

● Distributed Power

Features

● Wide Input Voltage Range: 6.5V to 76V

● Fixed (3.3V, 5V) and Adjustable (1.265V to 11V)

Output-Voltage Versions

● 2A Output Current

● Efficiency Up to 92%

● Internal 0.26Ω High-Side DMOS FET

● 310µA Quiescent Current at No Load

● 19µA Shutdown Current

● Internal Frequency Compensation

● Fixed 127kHz Switching Frequency

● External Frequency Synchronization

● Thermal Shutdown and Short-Circuit Current Limit

● -40°C to +125°C Automotive Temperature Range

● 6-Pin (5mm x 5mm) Thin QFN Package

● Capable of Dissipating 2.67W at +70°C

Ordering Information continued at end of data sheet.

19-3872; Rev 1; 9/14

+Denotes a lead(Pb)-free/RoHS-compliant package.

*EP = Exposed pad.

PART

TEMP

RANGE

PIN-

PACKAGE

OUTPUT

VOLTAGE

(V)

MAX5090AATE+ -40°C to +125°C 16 TQFN-EP* 3.3

MAX5090AATE -40°C to +125°C 16 TQFN-EP* 3.3

MAX5090BATE+ -40°C to +125°C 16 TQFN-EP* 5.0

MAX5090BATE -40°C to +125°C 16 TQFN-EP* 5.0

PGND

BST

SGND

OUT

5V/2A

100µH

BST

0.22µF

3.3µF

ON/OFF

OUT

100µF

SYNC

PDS5100H

DRAIN

0.047µF

68µF

BYPASS

0.47µF

10Ω

7.5V TO 76V

MAX5090B

N.C.

ON/OFF

PGND

1 2

DRAIN

11 9

N.C.

SYNC

MA5090

BST SGND

DRAIN

TQFN

TOP VIEW

MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower

Step-Down DC-DC Converters

Typical Operating Circuit

Pin Conguration

Ordering Information

EVALUATION KIT AVAILABLE

Summary of content (17 pages)

PAGE 1
EVALUATION KIT AVAILABLE MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters General Description The MAX5090A/B/C easy-to-use, high-efficiency, highvoltage step-down DC-DC converters operate from an input voltage up to 76V, and consume only 310µA quiescent current at no load.
PAGE 2
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Absolute Maximum Ratings (Voltages referenced to PGND, unless otherwise specified.) VIN, DRAIN.............................................................-0.3V to +80V SGND, PGND........................................................-0.3V to +0.3V LX................................................................-0.8V to (VIN + 0.3V) BST...............................................................-0.3V to (VIN + 10V) BST to LX..
PAGE 3
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Electrical Characteristics (continued) (VIN = +12V, VON/OFF = +12V, VSYNC = 0V, IOUT = 0, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. See the Typical Operating Circuit.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP 3.3 MAX UNITS INTERNAL SWITCH/CURRENT LIMIT Peak Switch Current Limit ILIM (Note 3) 2.
PAGE 4
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Typical Operating Characteristics (VIN = 12V, VON/OFF =12V, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. See the Typical Operating Circuit, if applicable.) 3.36 5.10 5.05 IOUT = 0 3.32 3.30 3.26 4.95 IOUT = 2A 3.24 -25 0 25 50 75 4.85 100 125 150 3.22 -50 -25 0 25 50 75 3.20 100 125 150 3.38 3.36 3.34 36 46 56 66 5.10 VOUT (V) 36 46 56 66 76 3.20 0.
PAGE 5
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Typical Operating Characteristics (continued) (VIN = 12V, VON/OFF =12V, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. See the Typical Operating Circuit, if applicable.) 2.0 1.5 -25 0 25 50 75 3.0 2.0 1.0 100 125 150 6.5 16 26 NO-LOAD SUPPLY CURRENT vs. TEMPERATURE (MAX5090AATE) VOUT = 3.3V 500 450 400 350 -50 -25 0 25 50 75 600 4.0 3.0 2.0 1.0 76 500 450 400 350 6.
PAGE 6
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Typical Operating Characteristics (continued) (VIN = 12V, VON/OFF =12V, TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C. See the Typical Operating Circuit, if applicable.) LX WAVEFORMS (MAX5090AATE) LOAD-TRANSIENT RESPONSE (MAX5090AATE) MAX5090 toc19 LX WAVEFORMS (MAX5090AATE) MAX5090 toc20 MAX5090 toc21 VOUT = 3.3V A A A VOUT = 3.3V VOUT = 3.
PAGE 7
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Pin Description PIN NAME FUNCTION 1, 2 LX 3 BST Source Connection of Internal High-Side Switch 4 VIN Input Voltage. Bypass VIN to SGND with a low-ESR capacitor as close as possible to the device. 5 VD Internal Regulator Output. Bypass VD to PGND with a 3.3µF/10V or greater ceramic capacitor. 6 SYNC 7 SS Soft-Start Capacitor Connection. Connect an external capacitor from SS to SGND to adjust the soft-start time.
PAGE 8
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Simplified Functional Diagram ON/OFF ENABLE 1.38V VD DRAIN VIN REGULATOR (FOR DRIVER) REGULATOR (FOR ANALOG) IREF-PFM CPFM HIGH-SIDE CURRENT SENSE OSC VREF RAMP CILIM IREF-LIM CLKI RMP BST SRMP SYNC SRAMP SCK MUX MAX5090 SS CLK MIN FB RAMP *RH x1 N LX TYPE 3 COMPENSATION *RL CONTROL LOGIC EAMP CPWM THERMAL SHUTDOWN PGND *RH = 0Ω AND RL = ∞ FOR MAX5090C SGND www.maximintegrated.
PAGE 9
MAX5090A/B/C Boost High-Side Gate Drive (BST) Connect a flying bootstrap capacitor between LX and BST to provide the gate-drive voltage to the high-side n-channel DMOS switch. The capacitor is alternately charged from the internally regulated output-voltage VD and placed across the high-side DMOS driver. Use a 0.22µF, 16V ceramic capacitor located as close as possible to the device. On startup, an internal low-side switch connects LX to ground and charges the BST capacitor to (VD - VDIODE).
PAGE 10
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters VIN 6.5V TO 76V R1 CIN 68µF RIN 10Ω CBYPASS 0.47µF VIN DRAIN VOUT 3.3V, 2A D1 PDS5100H COUT 100µF LX ON/OFF 0.22µF MAX5090A R2 100µH BST FB SS SYNC SGND 0.047µF VD PGND 3.3µF Figure 1. Fixed Output-Voltage Configuration VIN 7.5V TO 76V CIN 68µF RIN 10Ω CBYPASS 0.47µF VIN DRAIN VOUT 5.25V, 2A 100µH LX ON/OFF 0.22µF MAX5090C D1 PDS5100H R3 0.047µF R4 BST COUT 100µF FB SS SYNC SGND PGND VD 3.
PAGE 11
MAX5090A/B/C Thermal-overload protection is intended to protect the MAX5090 in the event of a fault condition. For normal circuit operation, do not exceed the absolute maximum junction temperature rating of TJ = +150°C. Setting the Output Voltage The MAX5090A/MAX5090B have preset output voltages of 3.3V and 5.0V, respectively. Connect FB to VOUT for the preset output voltage (Figure 1). The MAX5090C offers an adjustable output voltage.
PAGE 12
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters calculate the input capacitance and the ESR required for a specified ripple using the following equations: ∆VESR ∆IL   I OUT + 2    I OUT × D(1 − D) C IN = ∆VQ × f SW 800 700 ESR IN = VF_D1 (mV) where: 600 (V − VOUT ) × VOUT ∆IL = IN VIN × f SW × L D= 0 Low-ESR ceramic multilayer chip capacitors are recommended for size-optimized application.
PAGE 13
MAX5090A/B/C overshoot. Large output capacitors take longer than the programmed soft-start time (tSS) and cause error-amplifier saturation. This results in output overshoot. Use greater than 2ms soft-start time for a 100µF output capacitor. In a dynamic-load application, the allowable deviation of the output voltage during the fast transient load dictates the output capacitance value and the ESR. The output capacitors supply the step-load current until the controller responds with a greater duty cycle.
PAGE 14
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Application Circuit VIN CIN R1 RIN CBYPASS VIN DRAIN L1 LX ON/OFF MAX5090B R2 CBST D1 VOUT COUT BST FB SS SYNC SGND PGND VD CSS 3.3µF Figure 4. Fixed Output Voltage Table 2. Typical External Components Selection (Circuit of Figure 4) VIN (V) 6.5 to 76 7.5 to 76 www.maximintegrated.com VOUT (V) 3.3 5 IOUT (A) EXTERNAL COMPONENTS 2 MAX5090AATE CIN = 2 x 68µF/100V EEVFK2A680Q, Panasonic CBYPASS = 0.
PAGE 15
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Table 2. Typical External Components Selection (Circuit of Figure 4) (continued) VIN (V) 6.5 to 40 7.5 to 40 15 to 40 VOUT (V) IOUT (A) 3.3 5 11 EXTERNAL COMPONENTS 2 MAX5090AATE CIN = 330µF/50V EEVFK1H331Q, Panasonic CBYPASS = 0.47µF/50V, GRM21BR71H474KA, Murata COUT = 100µF/6.3V 6SVP100M, Sanyo CBST = 0.22µF/16V, GRM188R71C224K, Murata R1 = 0Ω R2 = Open RIN = 10Ω, ±1%, 0603 D1 = B360, Diodes Inc.
PAGE 16
MAX5090A/B/C VIN 12V 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters CIN 68µF RIN CBYPASS VIN DRAIN LX ON/OFF PTC Rt MAX5090B Ct VOUT 5V, 2A 100µH CBST D1 B360 COUT 100µF BST FB SS SYNC SGND PGND VD CSS 3.3µF *LOCATE PTC AS CLOSE TO HEAT-DISSIPATING COMPONENT AS POSSIBLE. Figure 5.
PAGE 17
MAX5090A/B/C 2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters Revision History REVISION NUMBER REVISION DATE PAGES CHANGED 0 3/06 Initial release — 1 9/14 No /V OPNs; Removed automotive reference from Applications section 1 DESCRIPTION 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.