MAX1762, MAX1791 High-Efficiency, 10-Pin µMAX, Step-Down Controllers for Notebooks

Description

The MAX1762/MAX1791 PWM step-down controllers provide high efficiency, excellent transient response, and high DC output accuracy needed for stepping down, high-voltage batteries to generate low-voltage CPU core, I/O, and chipset RAM supplies in notebook computers and PDAs.

Maxim's proprietary Quick-PWM™ pulse-width modulator is a free-running constant on-time type with input feed-forward. Its high operating frequency (300kHz) allows small external components to be utilized in PC board area-critical applications such as subnotebook computers and smart phones. PWM operation occurs at heavy loads, and automatic switchover to pulse-skipping operation occurs at lighter loads. The external high-side p-channel and low-side n-channel MOSFETs require no bootstrap components. The MAX1762/MAX1791 are simple, easy to compensate, and do not have the noise sensitivity of conventional fixed-frequency current-mode PWMs.

These devices achieve high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by their ability to drive synchronous-rectifier MOSFETs. The MAX1762/MAX1791 come in a 10-pin µMAX® package and offer two fixed voltages (Dual Mode™) for each device, 1.8V/2.5V/adj (MAX1762) and 3.3V/5.0V/adj (MAX1791).

Key Features

Applications/Uses

High Operating Frequency (300kHz)
No Current-Sense Resistor
Accurate Current Limit
±1% Total DC Error over Line and During Continuous Conduction
Dual Mode Fixed Output
- 1.8V/2.5V/adj (MAX1762)
- 3.3V/5.0V/adj (MAX1791)
0.5V to 5.5V Output Adjust Range
5V to 20V Input Range
Automatic Light-Load Pulse Skipping Operation
Free-Running On-Demand PWM
Foldback Mode™ UVLO
PFET/NFET Synchronous Buck
4.65V at 25mA Linear Regulator Output
5µA Shutdown Supply Current
230µA Quiescent Supply Current
10-Pin µMAX Package

	2-Way Pagers
	Analog Cellular Phones
	Digital Cellular Phones
	Digital Still Cameras
	Notebook Computers

Key Specifications: Step-Down Switching Regulators

Part Number

V_IN (min) (V)

V_IN (max) (V)

Min. V_OUT (V)

Max. V_OUT (V)

Preset V_OUT (V)

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^**

MAX1762

0.5

5.5

1.8
2.5

Preset
Resistor

0.41

300

•	Adjustable Frequency

•	Current Limit

•	Fixed Frequency/ PWM Operation

•

Shutdown

•	Soft Start

•	Synchronous Rectifier

Yes

uMAX/10

Yes

-40 to +85

$2.30 @ 1k

MAX1791

3.3

•	Adjustable Frequency

•	Fixed Frequency/ PWM Operation

•

Shutdown

•	Synchronous Rectifier

$2.30 @ 1k

See All Step-Down Switching Regulators (223)

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.

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

MAX1762

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX1762EUB

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN-1*

-40°C to +85°C

See data sheet

MAX1762EUB-T

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN-1*

-40°C to +85°C

See data sheet

MAX1762EUB+

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1762EUB+T

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1791

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX1791EUB

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN-1*

-40°C to +85°C

See data sheet

MAX1791EUB-T

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN-1*

-40°C to +85°C

See data sheet

MAX1791EUB+

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1791EUB+T

uMAX;10 pin;
Dwg: 21-0061L (PDF)
Use pkgcode/variation: U10CN+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

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