MAX1901, MAX1902, MAX1904 500kHz Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers

Description

The MAX1901/MAX1902/MAX1904 are buck-topology, step-down, switch-mode, power-supply controllers that generate logic-supply voltages in battery-powered systems. These high-performance, dual/triple-output devices include on-board power-up sequencing, power-good signaling with delay, digital soft-start, secondary winding control, low dropout circuitry, internal frequency-compensation networks, and automatic bootstrapping.

Up to 97% efficiency is achieved through synchronous rectification and Maxim's proprietary Idle Mode™ control scheme. Efficiency is greater than 80% over a 1000:1 load-current range, which extends battery life in system suspend or standby mode. Excellent dynamic response corrects output load transients within five clock cycles. Strong 1A on-board gate drivers ensure fast external N-channel MOSFET switching.

These devices feature a logic-controlled and synchronizable, fixed-frequency, pulse-width modulation (PWM) operating mode. This reduces noise and RF interference in sensitive mobile communications and pen-entry applications. Asserting the active-low SKIP pin enables fixed-frequency mode, for lowest noise under all load conditions.

The MAX1901/MAX1902/MAX1904 include two PWM regulators, adjustable from 2.5V to 5.5V with fixed 5.0V and 3.3V modes. All these devices include secondary feedback regulation, and the MAX1902 contains a 12V/120mA linear regulator. The MAX1901/MAX1904 include a secondary feedback input (SECFB), plus a control pin (STEER) that selects which PWM (3.3V or 5V) receives the secondary feedback signal. SECFB provides a method for adjusting the secondary winding voltage regulation point with an external resistor divider, and is intended to aid in creating auxiliary voltages other than fixed 12V.

The MAX1901/MAX1902 contain internal output overvoltage and undervoltage protection features.

Key Features

Applications/Uses

	97% Efficiency
	4.2V to 30V Input Range
	2.5V to 5.5V Dual Adjustable Outputs
	Selectable 3.3V and 5V Fixed or Adjustable Outputs (Dual Mode™)
	12V Linear Regulator
	Adjustable Secondary Feedback (MAX1901/MAX1904)
	5V/50mA Linear Regulator Output
	Precision 2.5V Reference Output
	Programmable Power-Up Sequencing
	Power-Good (active-low RESET) Output
	Output Overvoltage Protection (MAX1901/MAX1902)
	Output Undervoltage Shutdown (MAX1901/MAX1902)
	333kHz/500kHz Low-Noise, Fixed-Frequency Operation
	Low-Dropout, 98% Duty-Factor Operation
	2.5mW Typical Quiescent Power (12V input, both SMPSs on)
	4µA Typical Shutdown Current

	Desktop CPU Local DC-DC Converters
	Notebook and Subnotebook Computers
	PDAs and Mobile Communicators

Key Specifications: Step-Down Switching Regulators

Part Number

V_IN
(V)

V_OUT
(V)

Max. I_OUT
(A)

Output Adjust. Method

DC-DC Outputs

Oper. Freq.
(kHz)

Package/Pins

Smallest Available Pckg.
(mm²)

Price

min

max

min

max

≥

≤

max w/pins

See Notes

MAX1901

4.2

2.5

5.5

Resistor

330

MAX1902

81.6

MAX1904

See All Step-Down Switching Regulators (264)

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: 1-22 of 22

MAX1901

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX1901EAI

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28-1*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1901EAI-T

Active

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX1901EAI+

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1901EAI+T

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1901ETJ

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255-4*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1901ETJ-T

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255-4*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1901ETJ+

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1901ETJ+T

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1902

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX1902EAI

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28-1*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1902EAI-T

Active

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX1902EAI+

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1902EAI+T

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX1904BEAI+

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904BEAI+T

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904EAI

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28-1*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1904EAI-T

Active

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX1904EAI+

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904EAI+T

Active

SSOP;28 pin;81.6 mm²
Outline Drawing: 21-0056 (PDF)
Land Pattern: 90-0095 (PDF)
Use pkgcode/variation: A28+1*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904ETJ

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255-4*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX1904ETJ-T

Active

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX1904ETJ+

Active

TQFN;32 pin;26 mm²
Outline Drawing: 21-0140 (PDF)
Land Pattern: 90-0012 (PDF)
Use pkgcode/variation: T3255+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX1904ETJ+T

Active

Land Pattern: Not Available

-40°C to +85°C

See data sheet

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See All Step-Down Switching Regulators (264 Products)