Datasheet AIC1567CS, AIC1567 Datasheet (AIC)

AIC1567

5-bit DAC, Synchronous PWM Power Regulator

with Linear Controller

Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC www.analog.com.tw

DS-1567-00 TEL: [phone] FAX: [phone]

1

 FEATURES

 Switching Regulator and Low Dropout Linear

Regulator on single chip.

 Simple Voltage-Mode PWM Control.

 Dual N-Channel MOSFET Synchronous Drive.

 Fast Transient Response.

 ±1.0% 5-Bit Digital-to-Analog Output Voltage.

 Adjustable Current Limit Without External Sense

Resistor.

 Full 0% to 100% Duty Ratio.

 200KHz Free-Running Oscillator Programmable

up to 350KHz.

 Power-Good Output Voltage Monitor.

 Short Circuit Protection with Low Short Circuit

Output Current.

 APPLICATIONS

 Power Supply for Pentium II, Power PC and

Alpha Microprocessors.

 High-Power 5V to 3.xV DC/DC Regulators.

 Low-Voltage Distributed Power Supplies.

 DESCRIPTION

The AIC1567 is a high power, high efficiency

switching regulator controller optimized for high

performance microprocessor applications. It is

designed to drive dual N-channel MOSFET in a

standard synchronous buck topology.

Featuring a low dropout linear regulator and a

digitally programmable switching regulator, the

AIC1567 includes monitoring and protection

capabilities in addition to all the essential

synchronous PWM control functions.

The internal 5-bit Digital-to-Analog Converter

(DAC) adjusts the output voltage from 2.0V to

3.5V in 0.1V increments and 1.3V to 2.0V in

0.05V increments. The precision reference and

voltage-mode control can provide output

regulation within ±1.0% over temperature and

line voltage shifts.

The internal oscillator of the AIC1567 free-runs

at 200KHz and can be adjusted up to 350KHz.

The resulting PWM duty ratio ranges from 0% to

100%. The error amplifier features a 11MHz

bandwidth and 6V/µS slew rate, which enables

high converter bandwidth for fast transient

response.

AIC1567

2

 ORDERING INFORMATION

AIC1567 XX

PACKAGE TYPE
S: SMALL OUTLINE

TEMPERATURE RANGE
C: 0°C~70°C

PIN CONFIGURATION

ORDER NUMBER

AIC1567CS
(PLASTIC SO)

TOP VIEW

RT

OVP

VCC

LGATE

PGND

BOOT

UGATE

PHASE

PGOOD

GND

LIDRI

VLFB

24

23

22

21

20

19

18

17

1

2

3

4

5

6

7

8

VSEN

OCSET

SS

VID0

VID1

VID2

VID3

VID4

COMP

FB

CLP

CLN

9

10

11

12

16

15

14

13

 TYPICAL APPLICATION CIRCUIT

VSEN RT
OCSET OVP
SS VCC

VID0 LGATE

VID1 PGND
VID2 BOOT

VID3 UGATE
VID4 PHASE
COMP PGOOD
FB GND
CLP LIDRI
CLN VLFB

C2

0.1

µ

F

C1

1

µ

F

C5

1000pF

C7

33pF

C6

1000pF

0.1µF

+

C1

1000

µ

F

5V

137
1%

R3

47K

R5

3.01K

Ω

R6

90.9K

R2

2.2K

C8

R1

237
1%

R7

+

1000µF

x 8

R4
15K

D1

1N5820

M2

NDP603AL

VID0

VID1
VID2

VID3
VID4

V

CORE

V

I/O

3.3V
10A

12V

AIC1567

M3
FD3055

0.1µF

R8

1.2M

C3
1000µF x 3

3µH

L2

M1

RFP45N03L

+

L1

1

µ

H

5V

C4

Pentium



II V

CORE

and V

I/O

DC/DC Converter

AIC1567

3

 ABSOLUTE MAXIMUM RATINGS

Supply Voltage, VCC....…..................................……………........................................... 15V

Boot Voltage, V

BOOT

………...................……………...................................................... 15V

Input, Output, or I/O Voltage .....…….........……………......…....... GND - 0.3V to VCC+0.3V

ESD Classification ...........................…………......................……......................... Class 2

Recommended Operating Conditions

Supply Voltage, VCC....…...................…………………..........................…….......... 12V±10%

Ambient Temperature Range ....……………………............................................ 0°C ~ 70°C

Junction Temperature Range ....…………………….......................................... 0°C ~100°C

Thermal Information

Thermal Resistance, θJA (Typical, Note 1)

SOIC Package .....................…….........……………………………….........…. 100°C/W

SOIC Package (with 3 in

2

of Copper) …………………………………......….. 90°C/W

Maximum Junction Temperature (Plastic Package) ….……………….…................... 150°C

Maximum Storage Temperature Range ……………………..……......…......... -65°C~150°C

Maximum Lead Temperature (Soldering 10 sec) …………………………......…......... 300°C

Note 1: symbol

θ

JA

is measured with the component mounted on an evaluation PC board in free air.

 TEST CIRCUIT

Refer to TYPICAL APPLICATION CIRCUIT.

 ELECTRICAL CHARACTERISTICS (VCC= 12V, Ta=25°

°°

°C, unless otherwise

specified.)

PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT

VCC Supply Current

Nominal Supply UGATE Open I

VCC

2mA

Power-On Reset

VCC Threshold V

OCSET

=4.5V 7 8.5 V

Rising V

OCSET

Threshold 1.26 V

Oscillator

Free Running Frequency RT Open 170 200 230 KHz

Total Variation 6KΩ< RT<200KΩ -20 +20 %

Ramp Amplitude RT Open ∆V

OSC

1.5 V

P-P

AIC1567

4

 ELECTRICAL CHARACTERISTICS (Continued)

PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT

Reference and DAC

DACOUT Voltage Accuracy V

DAC

=1.8V ~3.5V -1.0 +1.0 %

Error Amplifier

DC Gain 76 dB

Gain-Bandwidth Product GBW 11 MHz

Slew Rate SR 6 V/µS

Gate Driver

Upper Gate Source R

UGATE

8.0 12 Ω

Upper Gate Sink R

UGATE

5.5 10 Ω

Lower Gate Source R

LGATE

8.0 12 Ω

Lower Gate Sink R

LGATE

5.5 10 Ω

Protection

Over-Voltage Trip (V

SEN/DACOUT

) 106 115 125 %

OCSET Current Source

V

OCSET

=4.5VDC I

OCSET

170 200 230 µA

OVP Sourcing Current

V

VSEN

=5.5V, V

OVP

=0V I

OVP

30 mA

Soft Start Current I

SS

10 µA

Soft Start Sink Current under

Current Limit

V

VSEN

=V

DAC

, V

OCSET

=5.0V,

V

PHASE

=0V,

V

FB

=VDAC=50mV

130 µA

Soft Start Sink Current under

Hard Current Limit

V

VSEN

=0, V

OCSET

=5.0V,

V

PHASE

=0V, VFB=0V

65 mA

Power Good

Upper Threshold (V

VSEN

/V

DAC

)V

VSEN

Rising 106 114 %

Lower Threshold (V

VSEN

/ V

DAC )VVSEN

Falling 84 94 %

Hysteresis (V

VSEN

/ V

DAC

) Upper and Lower Threshold 2 %

PGOOD Voltage Low I

PGOOD

=5mA V

PGOOD

0.5 V

Linear Regulator

VLFB Feedback Voltage 1.18 1.21 1.24 V

VLFB Bias Current 40 nA

LIDRI Sourcing Current 10 mA

Current Limiting Threshold 10 20 30 mV

AIC1567

5



BLOCK DIAGRAM

PWM

COMPARATOR

CURRENT SENSE

LINEAR AMP.

ERROR

AMP

CLN

VDAC

1.2V

CLP

COMP

FB

VLFB

LIDRI

OSCILLATOR

REFERENCE

5BITS

DAC

RT

PHASE

OVER

CURRENT

VSEN

OCSET

SOFT

START

200µA

CONTROL

LOGIC

OVP

POW ER-ON

RESET

VCC

50%

POW ER

GOOD

90%

PGOOD

110%

115%

+

-

VID0

VID3

VID2

VID1

GND

BOOT

UGATE

10µA

4V

SS

+

-

+

-

+

-

+

-

+
+

-

+

-

+

-

+

-

+

-

20m

V

VID4

PGND

LGATE

OVP

VCC

AIC1567

6



PIN DESCRIPTIONS

PIN 1: VSEN - Converter output voltage sense

pin. Connect this pin to the
converter output. The PGOOD
and OVP comparator circuits use
this signal to report output
voltage status and for
overvoltage protection function.

PIN 2: OCSET - Current limit sense pin. Connect

a resistor R

OCSET

from this pin to
the drain of the external
MOSFET. R

OCSET

, an internal

200µA current source (I

OCS

), and

the external MOSFET on­resistance (R

DS(ON)

) jointly set
the over current trip point
according to the following
equation:

I

IR

R

PEA K

OCS OCSET

DS ON

=

×

()

If FB pin voltage is sensed to be
below 50% of the internal
voltage reference VDAC, the
over current comparator cycles
the soft-start function.

PIN 3: SS - Soft start pin. Connect a

capacitor from this pin to ground.
An internal 10µA current source
provides soft start function for
the converter.

PIN 4: VID0
PIN 5: VID1
PIN 6: VID2
PIN 7: VID3
PIN 8: VID4 - 5-bit DAC voltage select pin. TTL

inputs used to set the internal
voltage reference VDAC. When
left open, these pins are
internally pulled up to 5V and
provide logic ones. The level of
VDAC sets the converter output
voltage as well as the PGOOD
and OVP thresholds.

Table 1 specifies the VDAC
voltage for the 32 combinations
of DAC inputs.

PIN 9: COMP - External compensation pin. This

pin is connected to error
amplifier output and PWM

comparator. An RC network is
connected to FB pin to
compensate the voltage-control
feedback loop of the converter.

PIN 10: FB - The error amplifier inverting

input pin. The FB pin and COMP
pin are used to compensate the
voltage-control feedback loop.

PIN 11: CLP - Linear regulator current sense

pin. This pin is the positive input
of the current sense comparator.

PIN 12: CLN - Linear regulator current sense

pin. This pin is the negative input
of the current sense comparator.

PIN 13: VLFB - Negative feedback pin for the

linear regulator error amplifier.

PIN 14: LIDRI - Linear regulator output drive pin.

This pin can drive either a
Darlington NPN or an N-channel
MOSFET.

PIN 15: GND - Signal GND. It also serves as

the power GND for the upper
gate driver.

PIN 16: PGOOD-Power good indicator pin.

PGOOD is an open drain output.
This pin is pulled low when the
converter output is ±10% out of
the VDAC reference voltage.

Table 1. Output Voltage Program

VID4 VID3 VID2 VID1 VID0 VDAC

100003.5V

100013.4V

100103.3V

100113.2V

101003.1V

101013.0V

101102.9V

101112.8V

110002.7V

110012.6V

110102.5V

110112.4V

111002.3V

111012.2V

AIC1567

7

111102.1V

111112.0V

000002.05V

000012.00V

000101.95V

000111.90V

001001.85V

001011.80V

001101.75V

001111.70V

010001.65V

010011.60V

010101.55V

010111.50V

011001.45V

011011.40V

011101.35V

011111.30V

PIN 17: PHASE - Over current detection pin. Connect

the PHASE pin to source of the
external MOSFET. This pin detects
the voltage drop across the MOSFET
R

DS(ON)

for over-current protection.

PIN 18: UGATE- External MOSFET gate drive pin.

Connect UGATE to gate of the
external MOSFET.

PIN 19: BOOT - External MOSFET driver power

supply pin. To convert 5V main power

to V

CORE

power by driving N-channel
MOSFET, supply voltage of no higher
than 12V is recommended since the
negative power terminal of the
internal driver is internally tied to
GND.

PIN 20: PGND - Driver power GND pin. PGND should

be connected to a low impedance
ground plane in close to lower N­MOSFET source.

PIN 21: LGATE - Lower N-MOSFET gate driver pin.

PIN 22: VCC - The chip power supply pin. It also

serves as power supply for LGATE
driver. Recommended supply voltage
is 12V.

PIN 23: OVP -Over voltage indicator pin. This pin

also provides a driver source current
to turn on an external SCR in the
event of an over voltage condition.

PIN 24: RT - Frequency adjustment pin.

Connecting a resistor (RT) from this
pin to GND, increase the frequency
by the following equation.

FKHzST≅+

×

200

510

5

log R



PHYSICAL DIMENSIONS

 24 LEAD PLASTIC SO (300 mil) (unit: mm)

SYMBOL MIN MAX

A 2.35 2.65

A1 0.10 0.30

B 0.33 0.51

C 0.23 0.32

D 15.20 15.60

E 7.40 7.60

e 1.27(TYP)

H 10.00 10.65

e

B

D

A

A

1

C

E

H

L

L 0.40 1.27