DELL MAX1710, MAX1711 Schematics

	KIT	MANUAL
EVALUATION			SHEET
DATA
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Controllers for Notebook CPUs

Description

-down controllers are converters in notebook -threat combination of high DC accuracy, and -edge CPU core QUICK-PWM™ PWM control scheme ratios with ease and to load transients

constant switching fre-

a 2-wire remote-sens- for voltage drops in both

. An on-board, digital-to- output voltage in com-

CPU specifications.

efficiency at a reduced -sense resistor found in

. Efficiency is further very large synchronous-

allows these devices to batteries for the highest 2-stage conversion supply instead of the allows the mini-

are identical except that the MAX1711 has a 5-bit DAC rather than a 4-bit DAC. Also, the MAX1711 has a fixed overvoltage protection threshold at VOUT = 2.25V and undervoltage protection at VOUT = 0.8V, whereas the MAX1710 has variable thresholds that track VOUT. The MAX1711 is intended for applications where the DAC code may change dynamically.

Applications

Notebook Computers

Docking Stations

CPU Core DC-DC Converters

Single-Stage (BATT to VCORE) Converters

Two-Stage (+5V to VCORE) Converters

QUICK-PWM is a trademark of Maxim Integrated Products. Mobile Pentium II is a registered trademark of Intel Corp.

Pin Configuration appears at end of data sheet.

Features

♦Ultra-High Efficiency

♦No Current-Sense Resistor (Lossless ILIMIT)

♦QUICK-PWM with 100ns Load-Step Response

♦±1% V OUT Accuracy over Line and Load

♦4-Bit On-Board DAC (MAX1710)

♦5-Bit On-Board DAC (MAX1711)

♦0.925V to 2V Output Adjust Range (MAX1711)

♦2V to 28V Battery Input Range

♦200/300/400/550kHz Switching Frequency

♦Remote GND and VOUT Sensing

♦Over/Undervoltage Protection

♦1.7ms Digital Soft-Start

♦Drives Large Synchronous-Rectifier FETs

♦2V ±1% Reference Output

♦Power-Good Indicator

♦Small 24-Pin QSOP Package

Ordering Information

PART	TEMP. RANGE	PIN-PACKAGE
MAX1710EEG	-40°C to +85°C	24 QSOP
MAX1711EEG	-40°C to +85°C	24 QSOP

Minimal Operating Circuit

			BATTERY
+5V INPUT			4.5V TO 28V
	VCC	OVP*	VDD
	SHDN		V+
	FBS		BST
	ILIM
			DH
	GNDS
			OUTPUT
			0.925V TO 2V
	MAX1710		(MAX1711)
	MAX1711
	REF		LX
	CC		DL
	D0	PGND
	D1
D/A
	D2
INPUTS			FB
*MAX1710 ONLY	D3	SKIP
**MAX1711 ONLY	D4**	GND

________________________________________________________________ Maxim Integrated Products 1

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MAX1710/MAX1711

MAX1710/MAX1711

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

ABSOLUTE MAXIMUM RATINGS

V+ to GND ..............................................................	-0.3V to +30V	LX to BST..................................................................		- 6V to +0.3V
VCC, VDD to GND .....................................................	-0.3V to +6V	REF Short Circuit to GND ...........................................		Continuous
PGND to GND.....................................................................	±0.3V	Continuous Power Dissipation (TA = +70°C)
SHDN, PGOOD to GND ...........................................	-0.3V to +6V	24-Pin QSOP (derate 9.5mW/°C above +70°C)		..........762mW
OVP, ILIM, FB, FBS, CC, REF, D0–D4,	-0.3V to (VCC + 0.3V)	Operating Temperature Range ...........................	-40°C to +85°C
GNDS, TON to GND..............................		Junction Temperature......................................................		+150°C
SKIP to GND (Note 1).................................	-0.3V to (VCC + 0.3V)	Storage Temperature Range .............................	-65°C to +165°C
DL to PGND................................................	-0.3V to (VDD + 0.3V)	Lead Temperature (soldering, 10sec) .............................		+300°C
BST to GND ............................................................	-0.3V to +36V
DH to LX .....................................................	-0.3V to (BST + 0.3V)

Note 1: SKIP may be forced below -0.3V, temporarily exceeding the absolute maximum rating, for the purpose of debugging prototype breadboards using the no-fault test mode. Limit the current drawn to -5mA maximum.

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, VBATT = 15V, VCC = VDD = 5V, SKIP = GND, TA = 0°C to +85°C, unless otherwise noted.)

PARAMETER		CONDITIONS				MIN	TYP	MAX	UNIT
Input Voltage Range	Battery voltage, V+					2		28	V
	VCC, VDD					4.5		5.5
	VBATT = 4.5V to 28V, includes			DAC codes from 1.3V to 2V		-1		1
DC Output Voltage Accuracy									%
				DAC codes from 0.925V
	load regulation error					-1.2		1.2
				to 1.275V
Load Regulation Error	ILOAD = 0 to 7A						9		mV
Remote Sense Voltage Error	FB-FBS or GNDS-GND = 0 to 25mV						3		mV
Line Regulation Error	VCC = 4.5V to 5.5V, VBATT = 4.5V to 28V						5		mV
FB Input Bias Current	FB (MAX1710 only) or FBS					-0.2		0.2	µA
FB Input Resistance (MAX1711)						130	180	240	kΩ
GNDS Input Bias Current						-1		1	µA
Soft-Start Ramp Time	Rising edge of SHDN to full ILIM						1.7		ms
		TON = GND (550kHz)				140	160	180
	VBATT = 24V,
		TON = REF (400kHz)				175	200	225
On-Time	FB = 2V								ns
		TON = open (300kHz)				260	290	320
	(Note 2)
		TON = VCC (200kHz)				380	425	470
Minimum Off-Time	(Note 2)						400	500	ns
Quiescent Supply Current (VCC)	Measured at VCC, FB forced above the regulation point						600	950	µA
Quiescent Supply Current (VDD)	Measured at VDD, FB forced above the regulation point						<1	5	µA
Quiescent Battery Supply Current	Measured at V+						25	40	µA
Shutdown Supply Current (VCC)	SHDN = 0						<1	5	µA
Shutdown Supply Current (VDD)	SHDN = 0						<1	5	µA
Shutdown Battery Supply	SHDN = 0, measured at V+ = 28V, VCC = VDD = 0 or 5V						<1	5	µA
Current
Reference Voltage	VCC = 4.5V to 5.5V, no external REF load					1.98	2	2.02	V
Reference Load Regulation	IREF = 0 to 50µA							0.01	V
REF Sink Current	REF in regulation					10			µA
REF Fault Lockout Voltage	Falling edge, hysteresis = 40mV						1.6		V

2 _______________________________________________________________________________________

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, VBATT = 15V, VCC = VDD = 5V, SKIP = GND, TA = 0°C to +85°C, unless otherwise noted.)

	PARAMETER		CONDITIONS	MIN	TYP	MAX	UNIT
	Overvoltage Trip Threshold	With respect to unloaded output voltage (MAX1710)		10.5	12.5	14.5	%
		(MAX1711)		2.21	2.25	2.29	V
	Overvoltage Fault Propagation	FB forced 2% above trip threshold			1.5		µs
	Delay
	Output Undervoltage Protection	With respect to unloaded output voltage (MAX1710)		65	70	75	%
	Threshold	(MAX1711)		0.76	0.8	0.84	V
	Output Undervoltage Protection	From SHDN signal going high		10		30	ms
	Time
	Current-Limit Threshold	LX to PGND, ILIM tied to VCC		90	100	110	mV
	(Positive Direction, Fixed)
	Current-Limit Threshold	LX to PGND	RLIM = 100kΩ	40	50	60	mV
	(Positive Direction, Adjustable)		RLIM = 400kΩ	170	200	230
	Current-Limit Threshold	LX to PGND, TA = +25°C		-150	-120	-80	mV
	(Negative Direction)
	Current-Limit Threshold	LX to PGND			3		mV
	(Zero Crossing)
	PGOOD Propagation Delay	FB forced 2% below PGOOD trip threshold, falling edge			1.5		µs
	PGOOD Output Low Voltage	ISINK = 1mA				0.4	V
	PGOOD Leakage Current	High state, forced to 5.5V				1	µA
	Thermal Shutdown Threshold	Hysteresis = 10°C			150		°C
	VCC Undervoltage Lockout	Rising edge, hysteresis = 20mV,		4.1		4.4	V
	Threshold	PWM disabled below this level
	DH Gate-Driver On-Resistance	BST-LX forced to 5V				5	Ω
	DL Gate-Driver On-Resistance	DL, high state				5	Ω
	(Pull-Up)
	DL Gate-Driver On-Resistance	DL, low state			0.5	1.7	Ω
	(Pull-Down)
	DH Gate-Driver Source/Sink	DH forced to 2.5V, BST-LX forced to 5V			1		A
	Current
	DL Gate-Driver Sink Current	DL forced to 2.5V			3		A
	DL Gate-Driver Source Current	DL forced to 2.5V			1		A
	Dead Time	DL rising			35		ns
		DH rising			26
	SKIP Input Current Logic	To enable no-fault mode, TA = +25°C		-1.5		-0.1	mA
	Threshold
	PGOOD Trip Threshold	Measured at FB with respect to unloaded output voltage,		-8	-5	-3	%
		falling edge, hysteresis = 1%
	Logic Input High Voltage	D0–D4, SHDN, SKIP, OVP		2.4			V
	Logic Input Low Voltage	D0–D4, SHDN, SKIP, OVP				0.8	V
	Logic Input Current	SHDN, SKIP, OVP		-1		1	µA
	Logic Input Pull-Up Current	D0–D4, each forced to GND		3	5	10	µA

MAX1710/MAX1711

_______________________________________________________________________________________ 3

MAX1710/MAX1711

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, VBATT = 15V, VCC = VDD = 5V, SKIP = GND, TA = 0°C to +85°C, unless otherwise noted.)

PARAMETER	CONDITIONS		MIN	TYP	MAX	UNIT
TON VCC Level	TON logic input high level		VCC - 0.4			V
TON Float Voltage	TON logic input upper-mid-range level		3.15		3.85	V
TON Reference Level	TON logic input lower-mid-range level		1.65		2.35	V
TON GND Level	TON logic input low level				0.5	V
TON Logic Input Current	TON only, forced to GND or VCC		-3		3	µA

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, VBATT=15V, VCC = VDD = 5V, SKIP = GND, TA = -40°C to +85°C, unless otherwise noted.) (Note 3)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNIT

Input Voltage Range

Battery voltage, V+

2

28

V

VCC, VDD

4.5

5.5

VBATT = 4.5V to 28V, for all

DAC codes from 1.32V to 2V

-1.5

1.5

%

DC Output Voltage Accuracy

D/A codes, includes load

DAC codes from 0.925V to

-1.7

1.7

%

regulation error

1.275V

TON = GND (550kHz)

140

180

VBATT = 24V,

TON = REF (400kHz)

175

225

On-Time

FB = 2V

ns

TON = open (300kHz)

260

320

(Note 2)

TON = VCC (200kHz)

380

470

Minimum Off-Time

(Note 2)

500

ns

Quiescent Supply Current (VCC)

Measured at VCC, FB forced above the regulation point

950

µA

Reference Voltage

VCC = 4.5V to 5.5V, no external REF load

1.98

2.02

V

Overvoltage Trip Threshold

With respect to unloaded output voltage (MAX1710)

10

15

%

(MAX1711)

2.20

2.30

V

Output Undervoltage

With respect to unloaded output voltage (MAX1710)

65

75

%

Protection Threshold

(MAX1711)

0.75

0.85

V

Current-Limit Threshold

LX to PGND, ILIM tied to VCC

85

115

mV

(Positive Direction, Fixed)

Current-Limit Threshold

LX to PGND

RLIM = 100kΩ

35

65

mV

(Positive Direction, Adjustable)

RLIM = 400kΩ

160

240

VCC Undervoltage Lockout

Rising edge, hysteresis = 20mV, PWM disabled below

4.1

4.4

V

Threshold

this level

Logic Input High Voltage

D0–D4, SHDN, SKIP, OVP

2.4

V

Logic Input Low Voltage

D0–D4, SHDN, SKIP, OVP

0.8

V

Logic Input Current

SHDN, SKIP, OVP

-1

1

µA

Logic Input Pull-Up Current

D0–D4, each forced to GND

3

10

µA

4 _______________________________________________________________________________________

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, VBATT=15V, VCC = VDD = 5V, SKIP = GND, TA = -40°C to +85°C, unless otherwise noted.) (Note 3)

PARAMETER	CONDITIONS	MIN	TYP	MAX	UNIT
PGOOD Trip Threshold	Measured at FB with respect to unloaded output voltage,	-8.5		-2.5	%
	falling edge, hysteresis = 1%
PGOOD Output Low Voltage	ISINK = 1mA			0.4	V
PGOOD Leakage Current	High state, forced to 5.5V			1	µA

Note 2: On-Time and Off-Time specifications are measured from 50% point to 50% point at the DH pin with LX forced to 0V, BST forced to 5V, and a 250pF capacitor connected from DH to LX. Actual in-circuit times may differ due to MOSFET switching speeds.

Note 3: Specifications from -40°C to 0°C are guaranteed but not production tested.

__________________________________________Typical Operating Characteristics

(7A CPU supply circuit of Figure 1, TA = +25°C, unless otherwise noted.)

		EFFICIENCY vs. LOAD CURRENT						EFFICIENCY vs. LOAD CURRENT					EFFICIENCY vs. LOAD CURRENT
		(VO = 2.0V, f = 300kHz)						(VO = 1.6V, f = 300kHz)						(VO = 1.3V, f = 300kHz)
	100			-01		100		VIN = 4.5V		-02		100						-03
		VIN = 4.5V		MAX1710						MAX1710					VIN = 4.5V			MAX1710
								VIN = 7V
	90					90						90		VIN = 7V
(%)	80		VIN	= 7V	(%)	80					(%)	80
EFFICIENCY					EFFICIENCY						EFFICIENCY
	70	VIN = 15V				70			VIN = 15V			70
																VIN = 15V
	60	VIN = 24V				60		VIN = 24V				60
	50					50						50			VIN = 24V
	40					40						40
	0.01	0.1	1	10			0.01	0.1	1	10		0.01		0.1		1		10
		LOAD CURRENT (A)						LOAD CURRENT (A)						LOAD CURRENT (A)
		EFFICIENCY vs. LOAD CURRENT						FREQUENCY vs. LOAD CURRENT					FREQUENCY vs. INPUT VOLTAGE
		(VO = 1.6V, f = 550kHz)						(VO = 1.6V)
						350									(IO = 7A)
	100											320
		VIN = 4.5V		MAX1710-04						MAX1710-05								MAX1710-06
	90					300						318
		VIN = 7V				250	VIN = 15V, PWM MODE					316
(%)EFFICIENCY	60				(kHz)FREQUENCY			VIN = 15V, SKIP MODE			(kHz)FREQUENCY	314
	80
						200	VIN = 4.5V, SKIP MODE					312			VO = 2.0V
	70											310
						150							VO = 1.6V
		VIN = 15V										308
						100						306
	50	VIN = 24V				50						304
									TON = OPEN			302
	40					0										TON = OPEN
							0.01	0.1	1	10		300
	0.01	0.1	1	10
												0	5	10	15	20	25	30
		LOAD CURRENT (A)						LOAD CURRENT (A)
														INPUT VOLTAGE (V)

MAX1710/MAX1711

_______________________________________________________________________________________ 5

MAX1710/MAX1711

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

_____________________________Typical Operating Characteristics (continued)

(7A CPU supply circuit of Figure 1, TA = +25°C, unless otherwise noted.)

		FREQUENCY vs. TEMPERATURE											ON-TIME vs. TEMPERATURE										CURRENT-LIMIT TRIP POINT
			(VIN = 15V, VO = 2.0V)																					vs. TEMPERATURE
	315								MAX1710-07		474									MAX1710-08		30								MAX1710-09
	310						IO = 7A				472					IO = 1A						25
											470										(A)						ILIM = 400kΩ
(kHz)FREQUENCY										(ns)TIMEON
	305										468										POINTTRIPCURRENT	20
	300						IO = 4A				466											15
											464
																												ILIM = VCC
	295										462											10
	290										460					IO = 4A OR 7A						5
											458																ILIM = 100kΩ
		TON = OPEN					IO = 1A
	285
											456											0
	-60	-40	-20	0	20	40	60	80	100			-60	-40	-20	0	20	40	60	80	100		-60	-40	-20	0	20	40	60	80	100
				TEMPERATURE (°C)											TEMPERATURE (°C)										TEMPERATURE (°C)

		0.9
		0.8
		0.7
	(A)	0.6
	CURRENT
		0.5
	LOAD	0.4
		0.3
		0.2

0.1

0

0

		0.7
		0.6
	(mA)	0.5
	CURRENT	0.4
	SUPPLY	0.3
		0.2
		0.1
		0

0

CONTINUOUS TO DISCONTINUOUS INDUCTOR CURRENT POINT

vs. INPUT VOLTAGE

			MAX1710-10
	VO = 2.0V

VO = 1.6V

VO = 1.3V

5	10	15	20	25	30
	INPUT VOLTAGE (V)

NO-LOAD SUPPLY CURRENTS vs. INPUT VOLTAGE

(SKIP MODE, f = 550kHz)

		-13
		MAX1710
	ICC

IBATT

IDD

5

10

15

20

25

30

INPUT VOLTAGE (V)

		14.0
		13.5
	(A)	13.0
	CURRENT	12.5
	INDUCTOR	12.0
		11.5
		11.0
		10.5
		10.0

0

		20
		18
	(mA)	16
		14
	CURRENT
		12
	SUPPLY	10
		6
		8

4

2

0

0

INDUCTOR CURRENT PEAKS AND VALLEYS vs. INPUT VOLTAGE (AT CURRENT-LIMIT POINT)

11-MAX1710

IPEAK

IVALLEY

5	10	15	20	25	30
	INPUT VOLTAGE (V)

NO-LOAD SUPPLY CURRENTS vs. INPUT VOLTAGE

(PWM MODE, f = 300kHz)

													MAX1710-14
	IDD
		IBAT
					ICC
5	10					15		20		25		30

INPUT VOLTAGE (V)

		0.7
		0.6
	(mA)	0.5
	CURRENT	0.4
	SUPPLY	0.3
		0.2
		0.1
		0

0

		20
		18
	(mA)	16
		14
	CURRENT
		12
	SUPPLY	10
		6
		8

4

2

0

0

NO-LOAD SUPPLY CURRENTS vs. INPUT VOLTAGE

(SKIP MODE, f = 300kHz)

			-12
				MAX1710
ICC
		IBATT

IDD

5	10	15	20	25	30
	INPUT VOLTAGE (V)

NO-LOAD SUPPLY CURRENTS vs. INPUT VOLTAGE

(PWM MODE, f = 550kHz)

		-15
	IDD
		MAX1710

IBAT

ICC

5	10	15	20	25	30
	INPUT VOLTAGE (V)

6 _______________________________________________________________________________________

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

_____________________________Typical Operating Characteristics (continued)

(7A CPU supply circuit of Figure 1, TA = +25°C, unless otherwise noted.)

	LOAD-TRANSIENT RESPONSE			LOAD-TRANSIENT RESPONSE			LOAD-TRANSIENT RESPONSE
	(WITH INTEGRATOR)			(WITH INTEGRATOR)			(WITHOUT INTEGRATOR)
		MAX1710-16			MAX1710-17			MAX1710-18
A			A			A

B		B		B
	10μs/div		10μs/div		10μs/div
VIN = 15V, VO = 1.6V, IO = 0A TO 7A		VIN = 15V, VO = 1.6V, IO = 30mA, TO 7A		VIN = 15V, VO = 1.6V, IO = 30mA TO 7A
A = VOUT, AC COUPLED, 50mV/div		A = VOUT, AC COUPLED, 50mV/div		A = VOUT, AC COUPLED, 50mV/div
B = INDUCTOR CURRENT, 5A/div		B = INDUCTOR CURRENT, 5A/div		B = INDUCTOR CURRENT, 5A/div

MAX1710/MAX1711

LOAD-TRANSIENT RESPONSE	LOAD-TRANSIENT RESPONSE	START-UP WAVEFORM
(WITH INTEGRATOR)	(WITH INTEGRATOR)

A

B

C

20μs/div

VIN = 4.5V, VO = 2V, IO = 30mA TO 7A A = VOUT, AC COUPLED, 50mV/div

B = INDUCTOR CURRENT, 5A/div C = DL, 10V/div

MAX1710-19		MAX1710-20	A		MAX171021-
A
			B
B			C
C

20μs/div			500μs/div
VIN = 4.5V, VO = 1.3V, IO = 30mA TO 7A	A =	SHDN
A = VOUT, AC COUPLED, 50mV/div	B = VOUT, 0.5V/div
B = INDUCTOR CURRENT, 5A/div	C = INDUCTOR CURRENT, 5A/div
C = DL, 10V/div

_______________________________________________________________________________________ 7

MAX1710/MAX1711

High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

_____________________________Typical Operating Characteristics (continued)

(7A CPU supply circuit of Figure 1, TA = +25°C, unless otherwise noted.)

	OUTPUT OVERLOAD WAVEFORM				LOAD-TRANSIENT RESPONSE				SHUTDOWN WAVEFORM
		MAX1710-22					MAX1710-23			MAX1710-24
A					CERAMIC COUT
								A
B			A
								B
								C
			B
C								D
			C
	50μs/div					5μs/div			5μs/div
	VOUT = 1.6V		L = 0.7μH, VOUT = 1.6V, VIN = 15V, COUT = 47μF (x4), f = 550kHz					VIN = 15V, V0 = 1.6V, I0 = 7A
	A = VIN, AC COUPLED, 2V/div		A = VOUT, AC COUPLED, 100mV/div					A = VOUT, 0.5V/div
	B = VOUT, 0.5V/div		B = INDUCTOR CURRENT, 5A/div					B = INDUCTOR CURRENT, 5A/div
	C = INDUCTOR CURRENT, 5A/div		C = DL, 5V/div					C = SHDN, 2V/div

D = DL, 5V/div

Pin Description

	PIN	NAME		FUNCTION
	1	CC		Battery Voltage Sense Connection. V+ is used only for PWM one-shot timing. DH on-time is inversely propor-
				tional to V+ input voltage over a range of 2V to 28V.
	2	SHDN		Shutdown Control Input, active low. SHDN cannot withstand the battery voltage. In shutdown mode, DL is
				forced to VDD in order to enforce overvoltage protection, even when powered down (unless OVP is high).
	3	FB		Fast Feedback Input, normally connected to VOUT. FB is connected to the bulk output filter capacitors local-
				ly at the power supply. An external resistor-divider can optionally set the output voltage.
				Feedback Remote-Sense Input, normally connected to VOUT directly at the load. FBS internally connects to
	4	FBS		the integrator that fine-tunes the DC output voltage. Tie FBS to VCC to disable all three integrator amplifiers.
				Tie FBS to FB (or disable the integrators) when externally adjusting the output voltage with a resistor-divider.
5		CC		Integrator Capacitor Connection. Connect a 100pF to 1000pF (470pF typical) capacitor to GND to set the
				integration time constant.
				Current-Limit Threshold Adjustment. Connects to an external resistor to GND. The LX-PGND current-limit
	6	ILIM		threshold defaults to +100mV if ILIM is tied to VCC. The current-limit threshold is 1/10 of the voltage forced at
				ILIM. In adjustable mode the threshold is VTH = RLIM · 5µA/10.
	7	VCC		Analog Supply Voltage Input for PWM Core, 4.5V to 5.5V. Bypass VCC to GND with a 0.1µF minimum
				capacitor.
8		TON		On-Time Selection Control Input. This is a four-level input that sets the K factor to determine DH on-time.
				GND = 550kHz, REF = 400kHz, open = 300kHz, VCC = 200kHz.
				2.0V Reference Output. Bypass REF to GND with a 0.22µF minimum capacitor. REF can source 50µA for
	9	REF		external loads. Loading REF degrades FB accuracy according to the REF load-regulation error
				(see Electrical Characteristics).

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High-Speed, Digitally Adjusted Step-Down Controllers for Notebook CPUs

						Pin Description (continued)
		PIN	NAME		FUNCTION
		10	GND	Analog Ground
		11	GNDS	Ground Remote-Sense Input, normally connected to ground directly at the load. GNDS internally con-
				nects to the integrator that fine-tunes the ground offset voltage.
		12	PGOOD	Open-Drain Power-Good Output.
	13		DL	Low-Side Gate-Driver Output, swings 0 to VDD.
		14	PGND	Power Ground. Also used as the inverting input for the current-limit comparator.
		15	VDD	Supply Voltage Input for the DL gate driver, 4.5V to 5.5V
		16	OVP	Overvoltage-Protection Disable Control Input (Table 3). GND = normal operation and overvoltage
		(MAX1710)		protection active, VCC = overvoltage protection disabled.
	16
			D4	DAC Code Input, MSB, 5µA internal pull-up to VCC (Tables 1 and 2).
		(MAX1711)
		17	D3	DAC Code Input. 5µA internal pull-up to VCC.
		18	D2	DAC Code Input. 5µA internal pull-up.
		19	D1	DAC Code Input. 5µA internal pull-up.
		20	D0	DAC Code Input LSB. 5µA internal pull-up.
				Low-Noise-Mode Selection Control Input. Low-noise forced-PWM mode causes inductor current
				recirculation at light loads and suppresses pulse-skipping operation. Normal operation prevents
		21	SKIP	current recirculation. SKIP can also be used to disable both overvoltage and undervoltage protection
				circuits and clear the fault latch (Figure 6). GND = normal operation, VCC = low-noise mode. Do not
				leave SKIP floating.
				Boost Flying-Capacitor Connection. An optional resistor in series with BST allows the DH pull-up
	22		BST	current to be adjusted (Figure 5). This technique of slowing the LX rise time can be used to prevent
				accidental turn-on of the low-side MOSFET due to excessive gate-drain capacitance.
				Inductor Connection. LX serves as the lower supply rail for the DH high-side gate driver. Also used
		23	LX	for the noninverting input to the current-limit comparator as well as the skip-mode zero-crossing com-
				parator.
	24		DH	High-Side Gate-Driver Output. Swings LX to BST.

MAX1710/MAX1711

Standard Application Circuit

The standard application circuit (Figure 1) generates a low-voltage, high-power rail for supplying up to 7A to the core CPU VCC in a notebook computer. This DC-DC converter steps down a battery or AC adapter voltage to sub-2V levels with high efficiency and accuracy, and represents a good compromise between size, efficiency, and cost.

See the MAX1710 EV kit manual for a list of components and suppliers.

Detailed Description

The MAX1710/MAX1711 buck controllers are targeted for low-voltage, high-current CPU power supplies for notebook computers. CPU cores typically exhibit 0 to 10A or greater load steps when the clock is throttled. The proprietary QUICK-PWM pulse-width modulator in the MAX1710/MAX1711 is specifically designed for handling these fast load steps while maintaining a relatively constant operating frequency and inductor operating point over a wide range of input voltages. The QUICKPWM architecture circumvents the poor load-transient timing problems of fixed-frequency current-mode PWMs

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