Richtek RT8207LGQW, RT8207LZQW, RT8207MGQW, RT8207MZQW Schematic

®

RT8207L/M

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

General Description

The RT8207L/M 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 RT8207L/M 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 RT8207L/M 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 RT8207L/M has all of the protection features including

thermal shutdown and is available in WQFN-24L 4x4 and

WQFN-20L 3x3 packages.

Features



 PWM Controller





 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





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





 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





 RoHS Compliant and Halogen Free



Applications

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

Supplies

 Notebook Computers

 SSTL18, SSTL15 and HSTL Bus Termination

©

DS8207L/M-07 April 2014 www.richtek.com

1

RT8207L/M

Ordering Information

RT8207L/M

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.

(2)

Pin 1 Orientation (2) : Quadrant 2, Follow EIA-481-D

Package Type QW : WQFN-24L 4x4 (W-Type) QW : WQFN-20L 3x3 (W-Type)

Lead Plating System G : Green (Halogen Free and Pb Free) Z : ECO (Ecological Element with Halogen Free and Pb free)

L : WQFN-24L 4x4 M : WQFN-20L 3x3

Marking Information

RT8207LGQW

EF= : Product Code

EF=YM

DNN

RT8207LZQW / RT8207LZQW(2)

EF YM

DNN

RT8207MGQW

J7=YM

DNN

RT8207MZQW

J7 YM

DNN

YMDNN : Date Code

EF : Product Code

YMDNN : Date Code

J7= : Product Code

YMDNN : Date Code

J7 : Product Code

YMDNN : Date Code

Pin Configurations

VTT

VLDOIN

VTTGND

VTTSNS

MODE

VTTREF

1

2

3

GND

NC

4

5

6

78910 1211

NC

VDDQ

GND

WQFN-24L 4x4 WQFN-20L 3x3

BOOT

FB

21 20 1924 2223

UGATE

25

S3

PHASE

S5

LGATE

18

17

16

15

14

13

TON

PGND NC CS VDDP VDD PGOOD

(TOP VIEW)

VLDOIN

BOOT

S3

S5

17181920

21

9876

UGATE

16

10

TON

PHASE

15

14

13

12

115

PGOOD

VTT

VTTGND

VTTSNS

VTTREF

1

2

3

GND

VDDQ VDD

GND

4

FB

LGATE PGND CS VDDP

©

DS8207L/M-07 April 2014www.richtek.com

2

Typical Application Circuit

2

1

5

V

D

P

D

V

5

D

O

G

O

P

V

T

1

C

F

µ

1

2

R

0

k

0

1

V

/

T

E

R

F

C

o

n

V

D

Q

C

o

n

D

c

h

s

i

e

a

g

r

o

M

1

R 5

.

1

2

C

1

F

µ

l

o

r

t

r

t

l

o

d

e

3

,

2

E

5

(

p

x

1

4

3

R

k

.

6

5

1

6

3

1

0

1

4

o

e

d

P

s

a

d

)

1

8 1

R

T

O

N

V

D

P

D

V

S

C

D

O

G

O

P

S

3

S5

MODE

N

D

G

PGND VTTGND

RT8207L/M

V

N

I

5

V

.

4

o

2

t

6

R

T

O

N

6

2

0

k

R

8

2

7

L

0

U

P

L

V

T

V

T

2

B

G

H

G

L

V

T

2

O

T

2

1

A

T

E

2

0

A

S

E

1

9

A

T

E

9

F

B

3

2

D

O

N

I

8

D

Q

2

4

V

T

2

S

N

5

R

E

F

5

0

R

6

B

C

4

0

1

.

µ

F

0

Q

S

C

2

0

3

2

N

0

3

S

C

8

1

0

µ

F

C

3

n

F

3

V

C

9

0

µ

1

F

3

x

V

D

Q

2

.

V

Q

1

B

S

C

0

9

1

L

1

µ

N

4

3

S

0

*

O

:

V 0

2

x

H

R

7

*

C

6

C

5

i

t

p

o

n

a

T

6

.

V

R

*

6

l

R

0

1

*

8

k

9

k

1

C

7

2

0

µ

F

C

9

0

1

.

µ

F

Figure 1. Adjustable Voltage Regulator for RT8207L

V

N

I

4

5

.

V

2

6

o

t

R

T

O

N

6

2

k

0

R

T

7

0

8

2

1

T

O

V

P

D

V

5

1

C

F

µ

1

2

R

0

k

0

1

D

O

G

O

P

V

T

V

/

T

R

E

F

C

o

n

V

D

Q

C

o

n

D

a

c

h

s

i

e

M

g

r

o

1

R

.

1

5

2

C

F

µ

1

l

o

r

t

r

t

l

o

e

d

2

,

3

E

(

5

3

R

.

6

5

x

e

o

s

p

P

d

1

k

1

a

d

1

5

V

4

V

6

C

3

P

0

S

1

S5

4

MODE

)

G

8

PGND

1

VTTGND

N

D

S

G

O

3

D

N

L

2

B

P

U

G

P

H

L

G

D

O

V

L

V

T

V

T

2

O

T

2

1

A

T

E

2

0

A

S

E

1

9

A

T

E

8

D

Q

2

3

D

N

O

I

2

4

V

T

2

S

N

S

5

T

R

E

F

9

F

B

5

0

R

6

C

4 1

.

0

µ

F

0

2

B

S

Q

C

2

0

3

S

3

N

0

C

7

µ

F

0

1

x

C

3

n

F

3

V G

V

C

8

1

0

µ

F

2

x

V

D

Q

V

1

8

.

1

/

5

.

Q

1

B

S

C

0

9

L

1

µ

4

N

3

S

0

V

T

0

9

.

V

/

0

H

R

7

*

C

5

*

O

*

:

o

i

t

p

5

V

7

.

V

C

6

2

0

µ

F

n

l

a

2

r

o

f

D

R

I

V

D

P

N

D

o

f

I

D

r

I

D

R

I

Figure 2. Fixed Voltage Regulator for RT8207L

DS8207L/M-07 April 2014 www.richtek.com

©

3

RT8207L/M

V

P

D

V

5

D

O

G

O

P

V

T

1

C

F

µ

1

2

R

0

k

0

1

V

/

T

E

R

F

C

o

l

o

r

t

n

V

D

Q

C

o

n

r

t

l

o

3

V

N

I

5

V

.

4

o

2

t

6

R

T

O

N

6

k

2

0

R

T

8

2

0

7

9

T

O

N

2

1

V

D

1

R 5

.

1

2

C

1

F

µ

2

1

,

E

x

(

p

1

D

V

3

R

k

.

6

5

1

3

S

C

0

1

G

O

P

7

S

3

8

S5

e

o

d

s

P

a

d

)

N

D

G

1

4

PGND

1

VTTGND

M

1

B

P

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

6

F

B

1

9

D

O

N

I

5

D

Q

2

0

V

T

2

S

N

4

R

E

F

5

0

R

6

B

C

4

0

1

.

µ

F

0

Q

S

C

2

0

3

2

N

0

3

S

C

8

1

0

µ

F

C

3

n

F

V

C

9

0

µ

1

F

3

x

V

D

Q

V

2

.

Q

1

B

S

C

0

9

1

L

1

µ

N

4

3

0

*

O

p

:

t

V 0

2

x

H

S

*

R

7

6

C

5

a

o

n

i

l

T

V

6

.

R

*

6

R 1

*

8

k

9

0

k

1

C

7

2

0

µ

F

C

9

0

1

.

µ

F

Figure 3. Adjustable Voltage Regulator for RT8207M

V

N

I

4

5

.

V

o

2

t

6

R

T

O

N

6

2

0

k

R

T

8

2

0

7

9

T

O

V

P

D

V

5

1

C

µ

F

1

2

R

k

0

1

D

O

G

O

P

V

T

V

T

/

T

E

R

C

F

o

n

D

V

D

Q

C

o

n

1

R

.

5

1

2

C

µ

F

1

o

l

r

t

r

t

o

l

,

3

2

E

1

(

3

R

.

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

S

G

O

3

N

D

M

1

B

P

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

E

S

1

5

A

T

E

5

D

Q

1

9

D

N

O

I

2

0

V

T

2

S

N

4

R

E

F

6

F

B

5

0

R

6

C

4 1

.

0

F

µ

0

2

S

B

C 3

Q

C

0

3

2

0

N

3

S

C

7

1

0

F

µ

x

3

n

F

V G

V

C

8

1

0

µ

F

x

2

V

D

Q

D

1

8

.

V

5

1

/

V

Q

1

B

S

0

C

9

L

1

µ

4

N

0

3

S

V

T

0

9

0

V

.

/

H

R

7

*

C

5

*

:

*

o

i

O

p

t

n

7

5

.

V

.

C

6

2

0

F

µ

a

l

2

o

f

r

D

R

I

V

D

P

D

N

o

f

I

D

r

I

R

D

I

Figure 4. Fixed Voltage Regulator for RT8207M

4

©

DS8207L/M-07 April 2014www.richtek.com

Functional Pin Description

Pin No.

WQFN-24L 4x4 WQFN-20L 3x3

1 1 VTTGND Power Ground Output for VTT LDO.

RT8207L/M

Pin Name Pin Function

2 2 VTTSNS

3,

25 (Exposed Pad)

3,

21 (Exposed Pad)

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.

Output Discharge Mode Setting. Connect to VDDQ for tracking

4 -- MODE

discharge. Connect to GND for non-tracking discharge. Connect to VDD for no discharge.

5 4 VTTREF Buffered Reference Output.

6, 7, 17 -- NC No Internal Connection.

Reference Input for VTT and VTTREF. Discharge current

8 5 VDDQ

sinking terminal for VDDQ non-tracking discharge. Output voltage feedback input for VDDQ output if the FB pin is connected to VDD or GND.

VDDQ Output Setting. Connect to GND for DDR3 (V

9 6 FB

1.5V) power supply. Connect to VDD for DDR2 (V power supply. Or connect to a resistive voltage divider from VDDQ to GND to adjust the output of PWM from 0.75V to 3.3V.

10 7 S3 S3 Signal Input.

11 8 S5 S5 Signal Input

Set the UGATE on time through a pull-up resistor connecting to

12 9 TON

13 10 PGOOD

VIN. Output discharge mode setting pin for RT8207M. Connect

to VIN for non-tracking discharge.

R

TON

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

VDDQ

=

VDDQ

= 1.8V)

14 11 VDD Supply Input for Analog Supply.

15 12 VDDP Supply Input for LGATE Gate Driver.

16 13 CS

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

18 14 PGND Power Ground for Low Side MOSFET.

19 15 LGATE Low Side Gate Driver Output for VDDQ.

Switch Node. External inductor connection for VDDQ and

20 16 PHASE

behave as the current sense comparator input for Low Side MOSFET R

DS(ON)

sensing.

21 17 UGATE High Side Gate Driver Output for VDDQ.

22 18 BOOT Boost Flying Capacitor Connection for VDDQ.

23 19 VLDOIN Power Supply for VTT LDO.

24 20 VTT Power Output for VTT LDO.

DS8207L/M-07 April 2014 www.richtek.com

©

5

RT8207L/M

Function Block Diagram

TRIG

0.75V V

On-time

Compute

1-SHOT

REF

VDDQ

TON

Comp

-

+

BOOT

R

PWM

QS

DRV

UGATE

FB

VDD

S5

115%V

70% V

REF

+

-

+

-

90% V

SS Timer

OV

UV

VDDQ

Latch

S1 Q

Latch

S1 Q

REF

Thermal

Shutdown

-

+

Min. T

Q TRIG

1-SHOT

PGOOD

Buck Controller for RT8207L/M

OFF

Diode

Emulation

+ +

-

SS Int.

GM

PHASE

VDDP

DRV

+

-

10µA

LGATE

PGND

CS

S5

S3

MODE

VTTSNS

GND

Discharge

Mode

Select

110% V

90% V

VTTREF

Thermal

Shutdown

+

-

+

VTTREF

+

-

+

-

+

-

VLDOIN

VTT

VTTGND

VTT LDO for RT8207L

6

©

DS8207L/M-07 April 2014www.richtek.com

S5

S3

Non-tracking

Discharge

VDDQ

Thermal

Shutdown

+

-

RT8207L/M

VTTREF

+

-

VLDOIN

VTTSNS

GND

110% V

90% V

-

VTTREF

+

VTT LDO for RT8207M

+

-

+

-

VTT

VTTGND

©

DS8207L/M-07 April 2014 www.richtek.com

7

RT8207L/M

Absolute Maximum Ratings (Note 1)

 Supply Input Voltage, TON to GND ------------------------------------------------------------------------------------- −0.3V to 32V  BOOT to PHASE ----------------------------------------------------------------------------------------------------------- −0.3V to 6V

 VDD, VDDP, CS, MODE, S3, S5, VTTSNS, VDDQ, VTTREF, VTT, VLDOIN,

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

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

 PHASE to GND

DC------------------------------------------------------------------------------------------------------------------------------ –1V to 32V

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

 LGATE to GND

DC------------------------------------------------------------------------------------------------------------------------------ –0.3V to 6V

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

 UGATE to PHASE

DC------------------------------------------------------------------------------------------------------------------------------ –0.3V to 6V

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

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

 Power Dissipation, P

WQFN-24L 4x4 ------------------------------------------------------------------------------------------------------------- 1.923W

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

 Package Thermal Resistance (Note 2)

WQFN-24L 4x4, θJA-------------------------------------------------------------------------------------------------------- 52°C/W

WQFN-24L 4x4, θJC------------------------------------------------------------------------------------------------------- 7°C/W

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

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

 Junction Temperature ------------------------------------------------------------------------------------------------------ 150°C

 Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------- 260°C  Storage Temperature Range --------------------------------------------------------------------------------------------- −65°C to 150°C

 ESD Susceptibility (Note 3)

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

MM (Machine Model) ------------------------------------------------------------------------------------------------------ 200V

@ T

D

= 25°C

A

Recommended Operating Conditions (Note 4)

 Supply Input Voltage, V

 Control Voltage, V  Junction Temperature Range --------------------------------------------------------------------------------------------- −40°C to 125°C  Ambient Temperature Range --------------------------------------------------------------------------------------------- −40°C to 85°C

©

DD

8

------------------------------------------------------------------------------------------------ 4.5V to 26V

IN

, V

--------------------------------------------------------------------------------------------- 4.5V to 5.5V

VDDP

DS8207L/M-07 April 2014www.richtek.com

Electrical Characteristics

(V

= 15V, V

IN

PWM Controller

Quiescent Supply Current

+ V

(V

DD

TON Operating Current R

I

VLDOIN

DD

= V

VDDP

= 5V, R

TON

= 1MΩ, T

Parameter Symbol Test Conditions Min Typ Max Unit

DDP

)

BIAS Current V

RT8207L/M

= 25°C, unless otherwise specified)

A

FB forced above the regulation point,

= 5V, VS3 = 0V

V

S5

= 1M -- 15 -- A

TON

= VS3 = 5V, VTT = No Load -- 1 -- A

S5

-- 470 1000 A

I

VLDOIN

Shutdown Current (V

FB Reference Voltage V

Fixed VDDQ Output Voltage

Standby Current V

I

S5

= V

S3

= 0V)

SHDN

REF

= 5V, V

S5

VDD + V

TON -- 0.1 5 S5/S3 = 0V 1 0.1 1

I

VLDOI N

V

= 4.5V to 5.5V 0.742 0.75 0.758 V

DD

FB = GND -- 1.5 --

FB = V

= 0V, VTT = No Load -- 0.1 10 A

S3

-- 1 10

VDDP

A

-- 0.1 1

V

-- 1.8 --

DD

FB Input Bias Current FB = 0.75V 1 0.1 1 A

VDDQ Voltage Range 0.75 -- 3.3 V

On-Time R

TON

= 1M, V

= 1.25V 267 334 401 ns

VDDQ

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

VDDQ Shutdown Discharge Resistance

V

= GND -- 15 -- 

S5

Current Sensing

CS Sink Current VCS > 4.5V, After UV Blank Time 9 10 11 A

Current Comparator Offset

GND  PHASE, R

= 5k 15 -- 15 mV

CS

Zero Crossing Threshold GND PHASE 5 -- 10 mV

Fault Protec tion

GND PHASE, RCS = 5k 35 50 65

Current Limit (Positive)

Under Voltage Protection Threshold Over Voltage Protection Threshold

Over Voltage Fault Delay

VDD POR Threshold

GND PHASE, R

V

60 70 80 %

UVP

V

OVP

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

= 20k 170 200 230

CS

110 11 5 12 0 %

-- 20 -- s

3.9 4.2 4.5 V

mV

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

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

Hysteresis

T

-- 10 -- °C

SD

DS8207L/M-07 April 2014 www.richtek.com

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