MAX8543, MAX8544 Step-Down Controllers with Prebias Startup, Lossless Sensing, Synchronization, and OVP

Description

The MAX8543/MAX8544 current-mode, constant-frequency PWM buck controllers operate from a 3V to 13.2V input supply and generate adjustable 0.8V to 0.9 x V_IN output voltages at loads up to 25A. They feature adjustable switching frequency and synchronization for noise-sensitive applications.

The MAX8543/MAX8544 can start with (or without) a preexisting bias on the output, without discharging the output. This feature simplifies tracking supply designs for core and I/O applications and redundant supply designs.

The MAX8543/MAX8544 use the DC resistance of the output inductor as the current-sense element for lossless, low-cost current sensing. The current-sense threshold can be set to four discrete levels to accommodate inductors with different DC resistance values.

The MAX8544 features a power-OK monitor and two MAX8544 controllers that can operate at 180° out-of-phase for dual-output applications.

Learn More About PowerMind™

Key Features

Applications/Uses

Prebias Startup/Monotonic
1% Output Accuracy
Ceramic, Polymer, or Electrolytic Capacitors
200kHz to 1MHz Adjustable Frequency
160kHz to 1.2MHz Synchronization
Lossless, Foldback Current Limit
Overvoltage Protection
Enable (On/Off)
Adjustable Soft-Start
MAX8544
- Latch-Off/Autorecovery
- Power-OK Monitor
- Out-of-Phase Clock Output

	Networks and Telecom
	Servers
	Storage
	Wireless Base Stations

Key Specifications: Step-Down Switching Regulators

Part Number

V_IN (min) (V)

V_IN (max) (V)

Min. V_OUT (V)

Max. V_OUT (V)

I_OUT (A)

Output Adj. Method

Operating Current, I_CC (max) (mA)

Number of DC-DC Outputs

Operating Freq. (kHz)

Features

EV-Kit

Package

RoHS Available

Operating Temp. Range (°C)

Price^**

MAX8543

13.2

0.8

Resistor

1000

•	Adjustable Frequency

•	Current Limit

•	External Synchronization

•	Fixed Frequency/ PWM Operation

•	Output Overvoltage Protection

•

Shutdown

•	Soft Start

•	Synchronous Rectifier

Yes

QSOP/16

Yes

-40 to +85

$1.05 @ 1k

MAX8544

•	Adjustable Frequency

•	Current Limit

•	External Synchronization

•	Fixed Frequency/ PWM Operation

•	Low Battery/ Power OK Output

•	Output Overvoltage Protection

•

Shutdown

•	Soft Start

•	Synchronous Rectifier

QSOP/20

$1.22 @ 1k

See All Step-Down Switching Regulators (223)

Key Specifications: Switch-Mode DC-DC Power Supplies

Part Number

Topology

V_IN (min) (V)

V_IN (max) (V)

Number of DC-DC Outputs

Digital/VID Programmed Output

Min. Adjustable V_OUT (V)

Max. Adjustable V_OUT (V)

I_OUT (A)

Operating Current, I_CC (max) (mA)

Operating Freq. (kHz)

Internal Power Switch(es)

Package

Price^**

MAX8543

Step-Down

13.2

0.8

1000

QSOP/16

$1.05 @ 1k

MAX8544

QSOP/20

$1.22 @ 1k

See All Switch-Mode DC-DC Power Supplies (429)

Notes:
^**This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Software/Models


		MAX8543 Mathcad Worksheet Use with the MAX8543 datasheet to speed the design of power supplies using the MAX8543. The Mathcad worksheet incorporates most of the equations in the datasheet along with equations and graphs of current waveforms, voltage noise and loop response. Requires Mathcad software that is able to run Mathcad 2000 worksheets.

Ordering Information

Notes:

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.
Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.
Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt. More: SeeFull Data Sheet or Part Naming Conventions.
* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Devices: 1-8 of 8

MAX8543

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8543EEE

QSOP;13 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E16-1*

-40°C to +85°C

See data sheet

MAX8543EEE-T

QSOP;13 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E16-1*

-40°C to +85°C

See data sheet

MAX8543EEE+

QSOP;16 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E16+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8543EEE+T

QSOP;16 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E16+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8544

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8544EEP

QSOP;20 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E20-1*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX8544EEP-T

QSOP;20 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E20-1*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX8544EEP+

QSOP;20 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E20+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8544EEP+T

QSOP;20 pin;
Dwg: 21-0055H (PDF)
Use pkgcode/variation: E20+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

Related Products

MAX1954A Low-Cost, Current-Mode PWM Buck Controller with Foldback Current Limit
MAX1953, MAX1954, MAX1957 Low-Cost, High-Frequency, Current-Mode PWM Buck Controllers
MAX8545, MAX8546, MAX8548 Low-Cost, Wide Input Range, Step-Down Controllers with Foldback Current Limit