Rainbow Electronics MAX1510 User Manual

General Description

The MAX1510 DDR linear regulator sources and sinks up
to 3A peak (typ) using internal n-channel MOSFETs. This
linear regulator delivers an accurate 0.5V to 1.5V output
from a low-voltage power input (V

IN

= 1.1V to 3.6V). The
MAX1510 uses a separate 3.3V bias supply to power the
control circuitry and drive the internal n-channel
MOSFETs.

The MAX1510 provides current and thermal limits to
prevent damage to the linear regulator. Additionally,
the MAX1510 generates a power-good (PGOOD) signal
to indicate that the output is in regulation. During start­up, PGOOD remains low until the output is in regulation
for 2ms (typ). The internal soft-start limits the input
surge current.

The MAX1510 powers the active-DDR termination bus
that requires a tracking input reference. The MAX1510
can also be used in low-power chipsets and graphics
processor cores that require dynamically adjustable
output voltages. The MAX1510 is available in a 10-pin
3mm x 3mm thin DFN package.

Applications

Notebook/Desktop Computers

DDR Memory Termination

Active Termination Buses

Graphics Processor Core Supplies

Chipset/RAM Supplies as Low as 0.5V

Features

♦ Internal Power MOSFETs with Current Limit (3A typ)

♦ Fast Load-Transient Response

♦ External Reference Input with Reference

Output Buffer

♦ 1.1V to 3.6V Power Input

♦ ±15mV (max) Load-Regulation Error

♦ Thermal Fault Protection

♦ Shutdown Input

♦ Power-Good Window Comparator with 2ms

(typ) Delay

♦ Small, Low-Profile 10-Pin 3mm x 3mm TDFN

Package

♦ Ceramic or Polymer Output Capacitors

MAX1510

Low-Voltage DDR Linear Regulator

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

OUT

IN

OUTS

AGND

PGND

V

OUT

= V

TT

V

IN

(1.1V TO 3.6V)

V

BIAS

(2.7V TO 3.6V)

V

DDQ

(2.5V OR 1.8V)

V

REFOUT

= V

TTR

REFOUT

MAX1510

V

CC

PGOOD

SHDN

REFIN

Typical Operating Circuit

19-3279; Rev 0; 5/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

EVALUATION KIT

AVAILABLE

Pin Configuration

PART TEMP RANGE

MAX1510ETB -40°C to +85°C

PIN-

PACKAGE

10 TDFN

(3mm x 3mm)

TOP

MARK

ABD

TOP VIEW

1 INREFOUT

2

V

CC

AGND

REFIN

3

4

5

3mm x 3mm

MAX1510

TDFN

10

98OUT

7

6

PGND

SHDN

OUTSPGOOD

MAX1510

Low-Voltage DDR Linear Regulator

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VIN= 1.8V, VCC= 3.3V, V

REFIN

= V

OUTS

= 1.25V, SHDN = VCC, circuit of Figure 1, TA= -40°C to +85°C, unless otherwise noted.

Typical values are at T

A

= +25°C.) (Note 1)

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.

IN to PGND...............................................................-0.3V to +4V

OUT to PGND ..............................................-0.3V to (V

IN

+ 0.3V)

OUTS to AGND............................................-0.3V to (V

IN

+ 0.3V)

V

CC

to AGND............................................................-0.3V to +4V

REFIN, REFOUT, SHDN, PGOOD to AGND ..-0.3V to (V

CC

+ 0.3V)

PGND to AGND .....................................................-0.3V to +0.3V

REFOUT Short Circuit to AGND .................................Continuous

OUT Continuous RMS Current: 100s ..................................±1.6A

1s......................................±2.5A

Continuous Power Dissipation (T

A

= +70°C)

10-Pin 3mm x 3mm Thin DFN

(derated 24.4mW/°C above +70°C)...........................1951mW

Operating Temperature Range

MAX1510ETB...................................................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

)

)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Input Voltage Range

Quiescent Supply Current (VCC)ICCLoad = 0, V

Shutdown Supply Current (VCC)I

Quiescent Supply Current (VIN)IINLoad = 0 0.4 10 mA

Shutdown Supply Current (VIN)I

Feedback-Voltage Error V

Load-Regulation Error -1A ≤ I

Line-Regulation Error 1.4V ≤ VIN ≤ 3.3V, I

OUTS Input Bias Current I

OUTPUT

Output Adjust Range 0.5 1.5 V

OUT On-Resistance

Output Current Slew Rate C

OUT Power-Supply Rejection
Ratio

OUT to OUTS Resistance R

Discharge MOSFET On­Resistance

V

V

CC(SHDN

IN(SHDN

OUTS

OUTS

PSRR

OUTS

R

DISCHARGE

IN

CC

Power input 1.1 3.6

Bias supply 2.7 3.6

> 0.45V 0.7 1.3 mA

REFIN

SHDN = GND, V

> 0.45V 350 600 µA

REFIN

SHDN = GND, REFIN = GND 50 100 µA

SHDN = GND 0.1 10 µA

REFIN to OUTS
I

= ±200mA

OUT

≤ +1A -15 +15 mV

OUT

High-side MOSFET (source) (I

Low-side MOSFET (sink) (I

= 100µF, I

OUT

10Hz < f < 10kHz, I

= 100µF

C

OUT

TA = 25°C-40+4

T

= -40°C to +85°C-6 +6

A

= ±100mA 1 mV

OUT

= 0.1A) 0.10 0.25

OUT

= -0.1A) 0.10 0.25

OUT

= 0.1A to 2A 3 A/µs

OUT

= 200mA,

OUT

SHDN = GND 8 Ω

-1 +1 µA

80 dB

12 kΩ

V

mV

Ω

MAX1510

Low-Voltage DDR Linear Regulator

_______________________________________________________________________________________ 3

Note 1: Limits are 100% production tested at TA= +25°C. Limits over the operating temperature range are guaranteed through cor-

relation using statistical-quality-control (SQC) methods.

ELECTRICAL CHARACTERISTICS (continued)

(VIN= 1.8V, VCC= 3.3V, V

REFIN

= V

OUTS

= 1.25V, SHDN = VCC, circuit of Figure 1, TA= -40°C to +85°C, unless otherwise noted.

Typical values are at T

A

= +25°C.) (Note 1)

REFERENCE

REFIN Voltage Range V

REFIN Input Bias Current I

REFIN Undervoltage-Lockout
Voltage

REFOUT Voltage V

REFOUT Load Regulation ∆V

FAULT DETECTION

Thermal-Shutdown Threshold T

VCC Undervoltage-Lockout
Threshold

IN Undervoltage-Lockout
Threshold

Current-Limit Threshold I

Soft-Start Current-Limit Time t

INPUTS AND OUTPUTS

PGOOD Lower Trip Threshold

PGOOD Upper Trip Threshold

PGOOD Propagation Delay t

PGOOD Startup Delay

PGOOD Output Low Voltage I

PGOOD Leakage Current I

SHDN Logic Input Threshold

SHDN Logic Input Current SHDN = VCC or GND -1 +1 µA

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

REFIN

REFIN

REFOUTVCC

REFOUTIREFOUT

SHDN

V

UVLO

LIMIT

SS

PGOOD

PGOOD

0.5 1.5 V

-1 +1 µA

Rising edge, hysteresis = 75mV 0.35 0.45 V

V

= 3.3V, I

= ±5mA -20 +20 mV

Rising edge, hysteresis = 15°C +165 °C

Rising edge, hysteresis = 100mV 2.45 2.55 2.65 V

Rising edge, hysteresis = 55mV 0.9 1.1 V

With respect to feedback threshold,
hysteresis = 12mV

With respect to feedback threshold,
hysteresis = 12mV

OUTS forced 25mV beyond PGOOD trip
threshold

Startup rising edge, OUTS within ±100mV of
the feedback threshold

= 4mA 0.3 V

SINK

OUTS = REFIN (PGOOD high impedance),
PGOOD = V

Logic high 2.0 V

Logic low 0.8 V

CC

REFOUT

+ 0.3V

= 0

REFIN

-0.01

-200 -150 -100 mV

V

REFIN

1.8 3 4.2 A

100 150 200 mV

51035µs

1 2 3.5 ms

V

REFIN

+0.01

200 µs

1µA

V

MAX1510

Low-Voltage DDR Linear Regulator

4 _______________________________________________________________________________________

Typical Operating Characteristics

(Circuit of Figure 1. TA = +25°C, unless otherwise noted)

INPUT CURRENT (IIN)

vs. INPUT VOLTAGE (V

IN

)

MAX1510 toc04

VIN (V)

I

IN

(µA)

3.02.52.01.51.00.5

50

100

150

200

250

0

0.0 3.5

V

OUT

= 1.25V

V

OUT

= 0.90V

0.96

OUTPUT LOAD REGULATION

0.94

(V)

V

OUT

0.92

0.90

0.88

0.86

V

VIN = 1.2V

REFIN

VIN = 1.5V

= 0.9V

MAX1510 toc01

(V)

V

OUT

1.300

1.275

1.250

1.225

OUTPUT LOAD REGULATION

V

REFIN

VIN = 1.8V

VIN = 1.5V

= 1.25V

3.0
V

OUT

2.5

MAX1510 toc02

2.0

1.5

1.0

MAXIMUM OUTPUT CURRENT (A)

0.5

MAXIMUM OUTPUT CURRENT

vs. INPUT VOLTAGE

= 0.9V

V

= 1.25V

OUT

THERMALLY LIMITED

DROPOUT VOLTAGE LIMITED

MAX1510 toc03

0.84

-3 3-2 -1 0 1 2
I

(A)

OUT

1.200

-3 3-2 -1 0 1 2
I

(A)

OUT

BIAS CURRENT (ICC)

vs. INPUT VOLTAGE (V

1.0

0.9

0.8

0.7

0.6

(mA)

0.5

IN

I

0.4

0.3

0.2

0.1

0.0

0.0 3.5

POWER GROUND CURRENT (I
vs. SOURCE LOAD CURRENT (I

0.25

0.20

0.15

(mA)

PGND

I

0.10

0.05

0.00

V

= 1.25V

OUT

V

= 0.90V

OUT

0.0 2.0
I

OUT

(A)

PGND

OUT

VIN = 1.5V

ENTERING
DROPOUT

1.51.00.5

)
)

MAX1510 toc07

(mA)

CC

I

vs. SINK LOAD CURRENT (I

7

6

5

4

3

V

= 1.25V

OUT

2

1

0

-2.0 0.0

DROPOUT

INPUT UVLO

VIN (V)

INPUT CURRENT (IIN)

V

= 0.90V

OUT

I

(A)

OUT

IN

V

OUT

VIN = 1.5V

-0.5-1.0-1.5

)

= 1.25V

3.02.51.5 2.01.00.5

OUT

MAX1510 toc05

)

MAX1510 toc08

0

1.0 1.5 2.0 2.5 3.0
INPUT VOLTAGE (V)

BIAS CURRENT (ICC)

vs. LOAD CURRENT (I

1.4

1.2

(mA)

CC

I

1.0

0.8

0.6

0.4

0.2

0.0

V

= 1.25V

OUT

V

= 0.90V

OUT

ENTERING
DROPOUT

-2 2
I

(A)

OUT

DROPOUT VOLTAGE

vs. OUTPUT CURRENT

0.6

0.5

V

0.4

0.3

0.2

DROPOUT VOLTAGE (V)

0.1

0

03.00.5 1.0 1.5 2.0 2.5

= 1.25V

OUT

V

= 0.9V

OUT

OUTPUT CURRENT (A)

)

OUT

VIN = 1.5V

10-1

MAX1510 toc06

MAX1510 toc09