Richtek RT8207PGQW, RT8561DGQW Schematic

®

RT8207P

Complete DDRII/DDRIII/Low-Power DDRIII/DDRIV Memory Power Supply Controller

General Description

The RT8207P provides a complete power supply for both

DDRII/DDRIII/Low-Power DDRIII/DDRIV memory systems.

It integrates a synchronous PWM buck controller with a

1.5A sink/source tracking linear regulator and buffered low

noise reference.

The PWM controller provides the high efficiency, excellent

transient response, and high DC output accuracy needed

for stepping down high voltage batteries to generate low

voltage chipset RAM supplies in notebook computers.

The constant-on-time PWM control scheme handles wide

input/output voltage ratios with ease and provides 100ns

“instant-on” response to load transients while maintaining

a relatively constant switching frequency.

The RT8207P achieves high efficiency at a reduced cost

by eliminating the current sense resistor found in

traditional current mode PWMs. Efficiency is further

enhanced by its ability to drive very large synchronous

rectifier MOSFETs. The buck conversion allows this device

to directly step down high voltage batteries for the highest

possible efficiency.

The 1.5A sink/source LDO maintains fast transient

response, only requiring 20μF of ceramic output

capacitance. In addition, the LDO supply input is available

externally to significantly reduce the total power losses.

The RT8207P supports all of the sleep state controls

placing VTT at high-Z in S3 and discharging VDDQ, VTT

and VTTREF (soft-off) in S4/S5.

The RT8207P has all of the protection features including

thermal shutdown and is available in a WQFN-20L 3x3

packages.

Features

zz

z PWM Controller

zz

``

` Resistor Progra mmable Current Limit by Low Side

``

R

``

` Quick Load Step Response Within 100ns

``

` 1% V

``

` Fixed 1.8V (DDRII), 1.5V (DDRIII) or Adjustable

``

DS(ON)

Sense

Accuracy Over Line and Load

VDDQ

0.75V to 3.3V Output Range for 1.35V (Low-Power DDRIII) and 1.2V (DDRIV)

``

` 4.5V to 26V Battery Input Range

``

` Resistor Programmable Frequency

``

` Over/Under Voltage Protection

``

` Internal Current Limit Ramp Soft-Start

``

` Drives Large Synchronous-Re ctifier FETs

``

` Power Good Indicator

``

zz

z 1.5A LDO (VTT), Buffered Reference (VTTREF)

zz

``

` Capable to Sink and Source 1.5A

``

` External Input Available to Minimize Power Losses

``

` Integrated Divider Tracks 1/2 VDDQ for Both VTT

``

and VTTREF

``

` Buffered Low Noise 10mA VTTREF Output

``

` Remote Sensing (VTTSNS)

``

±±

``

`

±20mV Accuracy for Both VTTREF and VTT

``

±±

``

` Supports High-Z in S3 and Soft-Off in S4/S5

``

zz

z RoHS Compliant and Halogen Free

zz

Ordering Information

RT8207P

Package Type QW : WQFN-20L 3x3 (W-Type)

Lead Plating System G : Green (Halogen Free and Pb Free)

Applications

z DDRI/II/III/Low-Power DDRIII/DDRIV Memory Power

Supplies

z Notebook Computers

z SSTL18, SSTL15 and HSTL Bus Termination

©

Note :

Richtek products are :

` RoHS compliant and compatible with the current require-

ments of IPC/JEDEC J-STD-020.

` Suitable for use in SnPb or Pb-free soldering processes.

DS8207P-01 October 2013 www.richtek.com

1

RT8207P

Marking Information

4B= : Product Code

4B=YM

DNN

YMDNN : Date Code

Pin Configurations

(TOP VIEW)

VTT

VLDOIN

VTTGND

VTTSNS

VTTREF

1

2

3

GND

VDDQ VDD

GND

4

S3

FB

WQFN-20L 3x3

BOOT

S5

17181920

21

9876

UGATE

16

10

TON

PHASE

15

14

13

12

115

PGOOD

LGATE PGND CS VDDP

©

DS8207P-01 October 2013www.richtek.com

2

Typical Application Circuit

9

V

D

P

V

5

C

1

F

µ

1

2

R

k

0

1

D

O

G

P

V

T

/

T

R

E

F

C

o

n

V

D

Q

D

C

o

n

1

R

.

5

1

2

C

F

µ

1

o

l

r

t

r

t

o

l

3

,

2

1

E

x

p

(

1

2

1

3

R

k

6

.

5

1

3

1

0

7

8

o

s

e

P

d

a

d

)

1

4 1

R

T

O

N

V

D

P

D

V

S

C

D

O

G

O

P

S

3

S5

D

N

G

PGND VTTGND

RT8207P

V

I

N

4

.

5

t

V

2

o

6

R

N

T

O

6

2

0

k

5

8

2

0

7

P

1

B

O

T

U

P

L

V

T

V

T

1

G

A

T

E

1

H

A

S

E

1

G

A

T

E

6

F

B

1

L

D

N

O

I

5

D

V

D

Q

2

V

T

2

T

S

N

S

4

T

R

E

F

R

0

8

0

6

R

7

4

C 0

.

1

µ

F

6

5

Q

B

S

C

2

0

3

2

N

0

3

S

9

0

C

8

1

0

µ

F

C

3

n

F

V

C

9

1

0

x

F

µ

3

V

D

Q

2

1

.

Q

1

B

S

C

0

9

L

1

µ

4

N

0

3

S

p

O

*

:

t

V 0

x

2

H

R

7

*

C

6

5

C

o

i

n

a

l

T

.

6

V

R

*

6

R 1

*

8

k

C

9

0

k

9

0

.

V

7

C 2

2

0

µ

F

1

F

µ

Figure 1. Adjustable Voltage Regulator

V

I

N

4

5

t

.

V

o

2

6

R

T

N

O

6

2

0

k

R

T

8

2

0

7

9

T

O

V

P

D

V

5

C

1

F

µ

1

2

R

k

0

1

D

O

G

P

V

T

V

T

/

T

R

E

F

C

o

n

V

D

Q

C

o

n

1

R

.

1

5

2

C

µ

1

o

l

r

t

o

l

r

t

3

,

2

E

1

(

3

R

F

.

6

5

x

p

o

s

e

d

P

1

k

1

a

d

1

2

V

1

V

3

C

0

P

7

S

8

S5

)

G

4

PGND

1

VTTGND

N

D

P

D

S

O

G

3

D

N

P

1

B

U

G

P

H

L

G

D

O

V

L

V

T

V

T

8

O

T

1

7

A

T

E

1

6

A

S

E

1

5

A

T

E

5

D

Q

1

9

O

D

I

N

2

0

V

T

2

S

N

S

4

R

E

F

6

F

B

5

0

R

6

4

C 0

1

.

µ

F

Q

B

S

C

C 3

3

2

0

3

2

N

0

3

S

7

C 1

0

x

µ

F

3

n

F

V G

V

8

C 1

0

µ

F

x

2

V

D

Q

1

8

.

1

5

V

/

.

Q

1

B

S

C

0

9

L

1

µ

4

0

N

3

S

V

T

0

9

.

V

0

/

H

R

7

*

5

C

*

p

O

*

:

o

n

i

t

a

7

.

5

V

C

6

2

0

µ

F

l

2

o

f

r

D

R

I

V

D

P

D

N

o

f

D

I

r

D

I

R

I

Figure 2. Fixed Voltage Regulator for

DS8207P-01 October 2013 www.richtek.com

©

3

RT8207P

Functional Pin Description

Pin No. Pin Name Pin Function

1 VTTGND Power Ground Output for VTT LDO.

2 VTTSNS

3,

21 (Exposed Pad)

4 VTTREF Buffered Reference Output.

5 VDDQ

6 FB

7 S3 S3 Signal Input.

8 S5 S5 Signal Input

9 TON Set the UGATE on time through a pull-up resistor connecting to VIN.

GND

Voltage Sense Input for VTT LDO. Connect to the terminal of the VTT LDO output capacitor.

Analog Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum thermal dissipation.

Reference Input for VTT and VTTREF. Discharge current sinking terminal for VDDQ non-tracking discharge. Output voltage feedback input for VDDQ output i f the FB pi n is connected to VDD or GND. VDDQ Output Setting. Connect to GND for DDR3 (V supply. Connect to VDD for DDR2 (V a resistive voltage divider from VDDQ to GND to adjust the output of PWM from

0.75V to 3.3V.

= 1.5V) power

VDD Q

= 1.8V) power supply. Or connect to

VDDQ

10 PGOOD

11 VDD Supply Input for Analog Supply.

12 VDDP Supply Input for LGATE Gate Driver.

13 CS

14 PGND Power Ground for Low Side MOSFET.

15 LGATE Low Side Gate Driver Output for VDDQ.

16 PHASE

17 UGATE High Side Gate Driver Output for VDDQ.

18 BOOT Boost Flying Capacitor Connection for VDDQ.

19 VLDOIN Power Supply for VTT LDO.

20 VTT Power Output for VTT LDO.

Power Good Open Drain Output. In High state when VDDQ output voltage is within the target range.

Current Limit Threshold Setting Input. Connect to VDD through the voltage setting resistor.

Switch Node. External inductor connection for VDDQ and behave as the current sense comparator input for Low Side MOSFET R

DS(ON)

sensing.

4

©

DS8207P-01 October 2013www.richtek.com

Function Block Diagram

Buck Controller

TRIG

0.75V V

On-time

Compute

1-SHOT

REF

VDDQ

TON

Comp

-

+

RT8207P

BOOT

R

PWM

QS

DRV

UGATE

FB

VDD

S5

VTT LDO

116%V

70% V

REF

+

-

+

-

90% V

SS Timer

OV

UV

S1 Q

REF

VDDQ

Latch

-

+

Thermal

Shutdown

Min. T

OFF

QTRIG

1-SHOT

Diode

Emulation

PGOOD

+ +

-

SS Int.

GM

PHASE

VDDP

DRV

+

-

10µA

LGATE

PGND

CS

S5

S3

VTTSNS

GND

©

Tracking

Discharge

110% V

90% V

VTTREF

Thermal

Shutdown

+

-

+

VTTREF

+

-

+

-

+

-

VLDOIN

VTT

VTTGND

DS8207P-01 October 2013 www.richtek.com

5

RT8207P

Absolute Maximum Ratings (Note 1)

z Supply Input Voltage, TON to GND------------------------------------------------------------------------------------- −0.3V to 32V

z BOOT to PHASE ----------------------------------------------------------------------------------------------------------- −0.3V to 6V

z VDD, VDDP, CS, S3, S5, VTTSNS, VDDQ, VTTREF, VTT, VLDOIN,

FB, PGOOD to GND ------------------------------------------------------------------------------------------------------- −0.3V to 6V

z PGND, VTTGND to GND -------------------------------------------------------------------------------------------------- −0.3V to 0.3V

z PHASE to GND

DC------------------------------------------------------------------------------------------------------------------------------ −1V to 32V

< 20ns ------------------------------------------------------------------------------------------------------------------------ −8V to 38V

z LGATE to GND

DC------------------------------------------------------------------------------------------------------------------------------ −0.3V to 6V

< 20ns ------------------------------------------------------------------------------------------------------------------------ −2.5V to 7.5V

z UGATE to PHASE

DC------------------------------------------------------------------------------------------------------------------------------ −0.3V to 6V

< 20ns ------------------------------------------------------------------------------------------------------------------------ −5V to 7.5V

z The Other Pins -------------------------------------------------------------------------------------------------------------- −0.3V to 6.5V

z Power Dissipation, P

WQFN-20L 3x3 ------------------------------------------------------------------------------------------------------------- 1.471W

z Package Thermal Resistance (Note 2)

WQFN-20L 3x3, θJA-------------------------------------------------------------------------------------------------------- 68°C/W

WQFN-20L 3x3, θJC------------------------------------------------------------------------------------------------------- 7.5°C/W

z Junction Temperature ------------------------------------------------------------------------------------------------------ 150°C

z Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------- 260°C

z Storage Temperature Range --------------------------------------------------------------------------------------------- − 65°C to 150°C

z ESD Susceptibility (Note 3)

HBM (Human Body Model)----------------------------------------------------------------------------------------------- 2kV

@ T

D

= 25°C

A

Recommended Operating Conditions (Note 4)

z Supply Input Voltage, VIN ------------------------------------------------------------------------------------------------ 4.5V to 26V

z Control Voltage, VDD, VDDP -------------------------------------------------------------------------------------------- 4.5V to 5.5V

z Junction Temperature Range --------------------------------------------------------------------------------------------- −40°C to 125°C

z Ambient Temperature Range --------------------------------------------------------------------------------------------- −40°C to 85°C

Electrical Characteristics

(V

= 15V, V

IN

PWM Controller

Quiescent Supply Current (V

+ V

DD

TON Operating Current R

I

VLDOIN

I

VLDOIN

6

©

DD

= V

VDDP

= 5V, R

TON

= 1MΩ, T

= 25°C, unless otherwise specified)

A

Parameter Symbol Test Conditions Min Typ Max Unit

DDP

)

BIAS Current V

Standby Current V

FB forced above the regulation point, V

= 5V, VS3 = 0V

S5

= 1MΩ -- 15 -- μA

TON

= VS3 = 5V, VTT = No Load -- 1 -- μA

S5

= 5V, V

= 0V, VTT = No Load -- 0.1 10 μA

S3

-- 470 1000 μA

DS8207P-01 October 2013www.richtek.com

RT8207P

Parameter Symbol Test Conditions Min Typ Max Unit

PWM Controller

VDD + V

Shutdown Current

= V

(V

S5

S3

= 0V)

FB Reference Voltage V

Fixed VDDQ Output Voltage

I

SHDN

V

REF

TON -- 0.1 5 S5/S3 = 0V −1 0.1 1

I

VLDOIN

= 4.5V to 5.5V 0.742 0.75 0.758 V

DD

FB = GND -- 1.5 --

FB = V

FB Input Bias Current FB = 0.75V −1 0.1 1 μA

VDDQ Voltage Range 0.75 -- 3.3 V

On-Time R

TON

= 1MΩ, V

Minimum Off-Time 250 400 550 ns VDDQ Input Resistance -- 100 -- kΩ

VDDQ Shutdown Discharge Resistance

V

= GND -- 15 -- Ω

S5

Current Sensing

CS Sink Current VCS > 4.5V 9 10 11 μA Current Limit Comparator

Offset

(V

VDD−CS

R

CS

= 10kΩ

Zero Crossing Threshold GND − PHASE −5 -- 10 mV

Current Limit Threshold Setting Range

V

– VCS 50 -- 200 mV

DD

Fault Protection

Under Voltage Protection Threshold Over Voltage Protection Threshold

Over Voltage Fault Delay

VDD POR Threshold

60 70 80 %

V

UVP

V

OVP

With respect to error comparator threshold FB forced above over voltage threshold Rising edge, hysteresis = 120mV, PWM disabled below this level

Under Voltage Blank Time From S5 signal going high -- 5 -- ms

Thermal Shutdown TSD -- 165 -- °C Thermal Shutdown

Hysteresis

-- 10 -- °C

ΔT

SD

Driver On-Resistance

UGATE Driver Source R

UGATE Driver Sink R

LGATE Driver Source R

LGATE Driver Sink R

Dead Time

UGATEsr

UGATEsk

LGAT Esr

LGAT Esk

BOOT − PHASE Forced to 5V -- 2.5 5 Ω

BOOT − PHASE Forced to 5V -- 1.5 3 Ω

DL, High State -- 2.5 5 Ω

DL, Low State -- 0.8 1.6 Ω

LGATE Rising (PHASE = 1.5V) -- 40 --

UGATE Rising -- 40 --

Internal Boost Charging Switch On Resistance

VDDP to BOOT, 10mA -- -- 80 Ω

-- 1 10

VDDP

μA

-- 0.1 1

V

-- 1.8 --

DD

= 1.25V 267 334 401 ns

VDDQ

– V

GND−PHAS E

),

−15 -- 15 mV

113 116 120 %

-- 20 -- μs

3.9 4.2 4.5 V

ns

DS8207P-01 October 2013 www.richtek.com

©

7

RT8207P

Parameter Symbol Test Conditions Min Typ Max Unit

Lo gic I/O

Logic Input Low Voltage S3, S5 Low -- -- 0.8 V

Logic Input High Voltage S3, S5 High 2 -- -- V Logic Input Current S3, S5 = VDD/GND −1 0 1 μA

PGOOD (upper side threshold decide by Over Voltage threshold)

Trip Threshold (Falling)

Trip Threshold (Hysteresis) -- 3 -- %

Fault Propagation Delay

Output Low Voltage I

Leakage Current I

High state, forced to 5V -- -- 1 μA

LEAK

VTT LDO

VTT Output Tolerance V

VTT Source Current Limit I

VTT Sink Current Limit I

VTTTOL

VTTOCLSRC

VTTOCLSNK

Measured at FB, with respect to reference, no load

Falling edge, FB forced below PGOOD trip threshold

= 1mA -- -- 0.4 V

SINK

V

= V

VDDQ

⎪= 0A

⎪ I

VTT

V ⎪ I

V0.95

PGOOD = High

V

V1.05

PGOOD = High

V

= V

VDDQ

⎪< 1A

VTT

= V

VDDQ

⎪< 1.2A

VTT

= V

VDDQ

⎪< 1.5A

VTT

V

⎛⎞

=×

TT

⎜⎟ ⎝⎠

= 0V -- 1.3 --

TT

V

⎛⎞

=×

TT

⎜⎟ ⎝⎠

= V

TT

VDDQ

= 1.2V/1.35/1.5V/1.8V,

LDOIN

= 1.2V/1.35/1.5V/1.8V,

LDOIN

= 1.2V/1.35,

LDOIN

= 1.5V/1.8V,

LDOIN

VDDQ

2

VDDQ

2

,

-- 1.3 --

−13 −10 −7 %

-- 2.5 -- μs

−20 -- 20

−30 -- 30

−40 -- 40

1.6 2.6 3.6

mV

A

V

⎛⎞

VTT Leakage Current I

VTTSNS Leakage Current I

VTT Discharge Current I

VTTREF Output Voltage V

VDDQS NS/2, VTTREF Output Voltage Tolerance

VTTR EF Source Current Limit

8

©

VTTLK

VTTSNSLK

DSCHRG

VTTREF

V

VTTREFTOL

I

VTTREFOCL

S5 = 5V, S3 = 0V,

I

V

= 1mA −1 -- 1 μA

SINK

VDDQ

V

VTT REF

V

LDOIN

⎪ I

VTTREF

V

LDOIN

⎪ I

VTTREF

V

TT

= 0V, V

=

= V

= 0.5V, S5 = S3 =0V 10 30 -- mA

TT

V

⎛⎞

VDDQ

⎜⎟

2

⎝⎠

= 1.5V,

VDDQ

⎪ <10mA

= V

VDDQ

= 1.8V,

⎪ <10mA

= 0V 10 40 80 mA

VDDQ

=

⎜⎟

2

⎝⎠

−10 -- 10 μA

0.9 /

--

0.75

−15 -- 15

−18 -- 18

DS8207P-01 October 2013www.richtek.com

-- V

mV

Richtek RT8207PGQW, RT8561DGQW Schematic [ru]