Fairchild FDMS3686S service manual

FDMS3686S

Power 56

G1

D1

G2

S2

D1

PHASE (S1/D2)

Top Bottom

PowerTrench® Power Stage

Asymmetric Dual N-Channel MOSFET

Features

Q1: N-Channel

 Max r  Max r

Q2: N-Channel

 Max r  Max r

 Low inductance packaging shortens rise/fall times, resulting in

lower switching losses

 MOSFET integration enables optimum layout for lower circuit

inductance and reduced switch node ringing

 RoHS Compliant

= 8 mΩ at VGS = 10 V, ID = 13 A

DS(on)

= 11 mΩ at VGS = 4.5 V, ID = 11 A

DS(on)

= 2.8 mΩ at VGS = 10 V, ID = 23 A

DS(on)

= 3.8 mΩ at VGS = 4.5 V, ID = 21 A

DS(on)

General Description

This device includes two specialized N-Channel MOSFETs in a dual PQFN package. The switch node has been internally connected to enable easy placement and routing of synchronous buck converters. The control MOSFET (Q1) and synchronous SyncFET (Q2) have been designed to provide optimal power efficiency.

Applications

 Computing  Communications  General Purpose Point of Load  Notebook VCORE

January 2012

FDMS3686S PowerTrench

®

Power Stage

MOSFET Maximum Ratings T

Symbol Parameter Q1 Q2 Units

V

DS

V

GS

I

D

E

AS

P

D

TJ, T

STG

Thermal Characteristics

R

θJA θJA

R

θJC

Package Marking and Ordering Information

Device Marking Device Package Reel Size Tape Width Quantity

Drain to Source Voltage 30 30 V Gate to Source Voltage (Note 3) ±20 ±20 V Drain Current -Continuous (Package limited) TC = 25 °C 30 55

-Continuous (Silicon limited) T

-Continuous T

-Pulsed 40 100 Single Pulse Avalanche Energy 40 Power Dissipation for Single Operation TA = 25 °C 2.2 Power Dissipation for Single Operation T Operating and Storage Junction Temperature Range -55 to +150 °C

Thermal Resistance, Junction to Ambient 57 Thermal Resistance, Junction to Ambient 125 Thermal Resistance, Junction to Case 3.5 2.0

22CA

F10CC

FDMS3686S Power 56 13 ” 12 mm 3000 units

= 25 °C unless otherwise noted

A

1

= 25 °C 54 123

C

= 25 °C 13

A

= 25 °C 1.0

A

1a

4 1a 1c

1a

1c

1b

23

4

60

1b

2.5

1d

1.0

1b

50

1d

120

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A

mJ

W

°C/WR

FDMS3686S PowerTrench

Electrical Characteristics T

= 25 °C unless otherwise noted

J

Symbol Parameter Test Conditions Type Min Typ Max Units

Off Characteristics

BV

ΔBV ΔT

I

DSS

I

GSS

DSS

DSS J

= 250 μA, VGS = 0 V

Drain to Source Breakdown Voltage Breakdown Voltage Temperature

Coefficient

D

I

= 1 mA, VGS = 0 V

D

ID = 250 μA, referenced to 25 °C I

= 10 mA, referenced to 25 °C

D

Zero Gate Voltage Drain Current VDS = 24 V, V Gate to Source Leakage Current,

Forwad

V

= 20 V, VDS= 0 V

GS

= 0 V

Q1Q230

30

Q1 Q2

V

15 19

500 100

100

mV/°C

1

I

On Characteristics

V

GS(th)

ΔV ΔT

r

DS(on)

g

FS

GS(th)

J

Gate to Source Threshold Voltage Gate to Source Threshold Voltage

Temperature Coefficient

Drain to Source On Resistance

Forward Transconductance

= VDS, ID = 250 μA

GS

V

= VDS, ID = 1 mA

GS

ID = 250 μA, referenced to 25 °C I

= 10 mA, referenced to 25 °C

D

= 10 V, ID = 13 A

V

GS

V

= 4.5 V, ID = 11 A

GS

V

= 10 V , ID = 13 A , TJ = 125 °C

GS

V

= 10 V, ID = 23 A

GS

V

= 4.5 V, ID = 21 A

GS

V

= 10 V , ID = 23 A , TJ = 125 °C

GS

V

= 5 V, ID = 13 A

DS

V

= 5 V, ID = 23 A

DS

Q1Q21.1

1.121.5

Q1 Q2

Q1

Q2

Q1 Q2

-6

-4

5.8

8.5

7.8

2.2

3.0

3.1 61

124

2.7

3.0 mV/°C

8

11

10.8

2.8

3.8

4.0

μA μA

nA nA

V

mΩ

S

®

Power Stage

Dynamic Characteristics

C

iss

C

oss

C

rss

R

g

Input Capacitance

Output Capacitance

Reverse Transfer Capacitance

Gate Resistance

Switching Characteristics

t

d(on)

t

r

t

d(off)

t

f

Q

g

gs

gd

Turn-On Delay Time

Rise Time

Turn-Off Delay Time

Fall Time

Total Gate Charge V

Gate to Source Gate Charge

Gate to Drain “Miller” Charge

1340

Q1:

= 15 V, VGS = 0 V, f = 1 MHZ

V

DS

Q2:

= 15 V, VGS = 0 V, f = 1 MHZ

V

DS

Q1 Q2

Q1Q20.2

0.2

1820

485 725

53 8680130

0.6

0.9

1785 2420

645 965

2 3

pF

Ω

8.2916 18

2.5410 10

20 23

32 36

2.2310 10

21 27

10 13

29 37

14 18

3.9

4.6

3.1

3.7

ns

nC

Q1:

= 15 V, ID = 13 A, R

V

DD

Q2:

= 15 V, ID = 23 A, R

V

DD

= 0 V to 10 V

GS

= 0 V to 4.5 V

GS

= 6 Ω

GEN

= 6 Ω

GEN

Q1 V

= 15 V,

DD

I

= 13 A

D

Q2 VDD = 15 V, I

= 23 A

D

Q1 Q2

2

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FDMS3686S PowerTrench

Electrical Characteristics T

= 25 °C unless otherwise noted

J

Symbol Parameter Test Conditions Type Min Typ Max Units

Drain-Source Diode Characteristics

1.2

V

= 0 V, IS = 2 A (Note 2)

GS

V

= 0 V, IS = 13 A (Note 2)

V

SD

t

rr

Q

rr

Notes:

1. R

is determined with the device mounted on a 1 in2 pad 2 oz copper pad on a 1.5 x 1.5 in. board of FR-4 material. R

qJA

by the user's board desi gn.

Source to Drain Diode Forward Voltage

Reverse Recovery Time

Reverse Recovery Charge

a. 57 °C/W when mounted on

2

a 1 in

pad of 2 oz copper

SS

SF

DF

DS

G

GS

V

= 0 V, IS = 2 A (Note 2)

GS

V

= 0 V, IS = 23 A (Note 2)

GS

Q1 I

= 13 A, di/dt = 100 A/μs

F

Q2 I

= 23 A, di/dt = 300 A/μs

F

DS

DF

G

SF

SS

Q1 Q1 Q2 Q2

Q1 Q2

is guaranteed by design while R

qJC

b. 50 °C/W when mounted on

2

pad of 2 oz copper

a 1 in

0.72

1.2

0.82

0.58

0.76 25

25

9

23

1.2

1.2 40

39 18

36

is determined

qCA

V

ns

nC

®

Power Stage

c. 125 °C/W when mounted on a minimum pad of 2 oz copper

SF

SS

DS

DF

SS

SF

DF

DS

G

2. Pulse Test: Pulse Width < 300 ms, Duty cycle < 2.0%.

3. As an N-ch device, the negative Vgs rating is for low duty cycle pulse ocurrence only. No continuous rating is implied.

4. Q1: EAS of 40 mJ is based on starting TJ = 25 oC; N-ch: L = 1 mH, IAS = 9 A, VDD = 27 V, VGS = 10 V. 100% test at L= 0.3 mH, IAS = 14 A. of 60 mJ is based on starting TJ = 25 oC; N-ch: L = 1 mH, IAS = 11 A, VDD = 27 V, VGS = 10 V. 100% test at L= 0.3 mH, IAS = 17 A.

Q2: E

AS

G

d. 120 °C/W when mounted on a minimum pad of 2 oz copper

3

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FDMS3686S PowerTrench

0.0 0.2 0.4 0.6 0.8 1.0

0

10

20

30

40

VGS = 4.5 V

VGS = 3.5 V

V

GS

= 6 V

VGS = 4 V

PULSE DURATION = 80 μs DUTY CYCLE = 0.5% MAX

VGS = 10 V

I

D

, DRAIN CURRENT (A)

V

DS

, DRAIN TO SOURCE VOLTAGE (V)

0 10203040

0

1

2

3

4

VGS = 6 V

VGS = 3.5 V

PULSE DURA TION = 80 μs DUTY CYCLE = 0.5% MAX

NORMALIZED

DRAIN TO SOURCE ON-RESISTA NCE

I

D

, DRAIN CURRENT (A)

V

GS

= 4 V

VGS = 4.5 V

V

GS

= 10 V

-75 -50 -25 0 25 50 75 100 125 150

0.6

0.8

1.0

1.2

1.4

1.6

ID = 13 A V

GS

= 10 V

NORMALIZED

DRAIN TO SOURCE ON-RESISTANCE

T

J

, JUNCTION TE MPERATURE (

o

C)

246810

0

4

8

12

16

20

TJ = 125 oC

ID = 13 A

TJ = 25 oC

V

GS

, GATE TO SOURCE VOLTA GE (V)

r

DS(on)

,

DRAIN TO

SOURCE ON-RESISTANCE

(mΩ)

PULSE DURATION = 80 μs DUTY CYCLE = 0.5% MAX

1.5 2.0 2.5 3.0 3.5 4.0

0

10

20

30

40

TJ = 150 oC

V

DS

= 5 V

PULSE DURATION = 80 μs DUTY CYCLE = 0.5% MAX

TJ = -55 oC

TJ = 25 oC

I

D

, DRAIN CURRENT (A)

VGS, GATE TO SOURCE VOLTAGE (V)

0.0 0.2 0.4 0.6 0.8 1.0 1.2

0.001

0.01

0.1

1

10

40

TJ = -55 oC

TJ = 25 oC

TJ = 150 oC

V

GS

= 0 V

I

S

, REVERSE DRAIN CURRENT (A)

VSD, BODY DIODE FORWARD VOLTAGE (V)

Typical Characteristics (Q1 N-Channel) T

Figure 1.

On Region Characteristics Figure 2.

= 25 °C unless otherwise noted

J

Norm a l i z e d O n - R e sistance

vs Drain Current and Gate Voltage

®

Power Stage

Fi g u r e 3. No r m alized O n Resist a n ce

vs Junction Temperature

Figure 5. Transfer Characteristics

Figure 4.

On-Res istance vs Gate to

Source Voltage

Figure 6.

Source to Drain Diode

Forward Voltage vs Source Current

4

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FDMS3686S PowerTrench

0 5 10 15 20 25

0

2

4

6

8

10

ID = 13 A

V

DD

= 20 V

V

DD

= 10 V

V

GS

, GATE TO SOURCE VOLTAGE (V)

Qg, GATE CHARGE (nC)

VDD = 15 V

0.1 1 10 30

10

100

1000

2000

f = 1 MHz V

GS

= 0 V

CAPACITANCE (pF)

VDS, DRAIN TO SOURCE VOLTAGE (V)

C

rss

C

oss

C

iss

0.001 0.01 0.1 1 10 100

1

10

70

TJ = 100 oC

TJ = 25 oC

TJ = 125 oC

tAV, TIME IN AVALANCHE (ms)

I

AS

, AVALANCHE CURRENT (A)

25 50 75 100 125 150

0

10

20

30

40

50

60

R

θJC

= 3.5 oC/W

V

GS

= 4.5 V

Limited by P ackage

V

GS

= 10 V

I

D

, DRAIN CURRENT (A)

T

A

, AMBIENT TEMPERATURE (

o

C)

0.01 0.1 1 10 100

0.01

0.1

1

10

100

DC

100 ms

10 ms

1 ms

1s

I

D

, DRAIN CURRENT (A)

VDS, DRAIN to SOURCE VOLTAGE (V)

THIS AREA IS

LIMITED BY r

DS(on)

SINGLE PULSE T

J

= MAX RATED

R

θJA

= 125

o

C/W

T

A

= 25

o

C

10s

100us

200

10-410-310-210

-1

110

100 1000

0.1

1

10

100

1000

SINGLE PULSE R

θJA

= 125

o

C/W

T

A

= 25

o

C

P(

PK

), PEAK TRANSIENT POWER (W)

t, PULSE WIDTH (sec)

Typical Characteristics (Q1 N-Channel) T

Figure 7.

Gate Charge Characteristics Figure 8.

= 25 °C unless otherwise noted

J

Capa c i t a nce v s D r ain

to Source Voltage

®

Power Stage

Figure 9.

Un c l a mp e d I nd u c tiv e

Switching Capability

Figure 11. Forward Bias Safe

Op

erating Area

Figure 10.

Maximum Continuous Drain

Current vs Case Temperature

Figure 12. Single Pulse Maximum

Power Dissipation

5

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