1/32
L6919C
December 2002
s
2 PHASE OPERATION WITH
SYNCRHONOUS RECTIFIER CONTROL
s
ULTRA FAST LOAD TRANSIENT RESPONSE
s
INTEGRATED HIGH CURRENT GATE
DRIVERS: UP TO 2A GATE CURRENT
s
TTL-COMPATIBLE 5 BIT PROGRAMMABLE
OUTPUT FROM 0.800V TO 1.550V WITH
25mV STEPS
s
DYNAMIC VID MANAGEMENT
s
0.6% OUTPUT VOLTAGE ACCURACY
s
10% ACTIVE CURRENT SHARING ACCURACY
s
DIGITAL 2048 STEP SOFT-START
s
OVERVOLTAGE PROTECTION
s
OVERCURRENT PROTECTION REALIZED
USING THE LOWER MOSFET'S R
dsON
OR A
SENSE RESISTOR
s
OSCILLATOR EXTERNALLY ADJUSTABLE
AND INTERNALLY FIXED AT 200kHz
s
POWER GOOD OUTPUT AND INHIBIT
FUNCTION
s
REMOTE SENSE BUFFER
s
PACKAGE: SO-28
APPLICATIONS
s
POWER SUPPLY FOR SERVERS AND
WORKSTATIONS
s
POWER SUPPLY FOR HIGH CURRENT
MICROPROCESSORS
s
DISTRIBUTED POWER SUPPLY
DESCRIPTION
The device is a power supply controller specifically de-
signed to provide a high performance DC/DC conver-
sion for high current microprocessors. The device
implements a dual-phase step-down controller with a
180 phase-shift between each phase. A precise 5-bit
digital to analog converter (DAC) allows adjusting the
output voltage from 0.800V to 1.550V with 25mV binary
steps managing On-The-Fly VID code changes.
The high precision internal reference assures the se-
lected output voltage to be within 0.6%. The high
peak current gate drive affords to have fast switching
to the external power mos providing low switching
losses.
The device assures a fast protection against load
over current and load over/under voltage. An internal
crowbar is provided turning on the low side mosfet if
an over-voltage is detected. In case of over-current,
the system works in Constant Current mode.
SO-28
ORDERING NUMBERS:L6919CD
L6919CDTR
5 BIT PROGRAMMABLE DUAL-PHASE CONTROLLER
WITH DYNAMIC VID MANAGEMENT
BLOCK DIAGRAM
CU R REN T
REA DIN G
I
FB
TO TA L
C U R R EN T
C
U
RRE
NT
AVG
CH1
O CP
D A C
D IGITAL
SOF T-START
LO
G
I
C
P
W
M
AD
A
P
T
I
VE
A
N
T
I
CR
O
S
S
C
O
ND
U
C
T
I
O
N
C H 1 OC P
2
PH
A
S
E
OS
C
I
L
L
A
T
OR
P W M1
CU
RR
E
N
T
CO
RR
E
C
T
I
O
N
ERR OR
A MPL IF IER
R EMO TE
BU FFE R
3 2k
3 2k
3 2k
L S
LS
H S
Vc c
H S
BO O T 1
U
GA T E1
PH AS E1
L GAT E1
ISE N1
PG N DS 1
PG N D
PG N DS 2
ISE N2
L GAT E2
PH AS E2
U GA T E2
BO O T 2
V cc
CO M P
FB
V S EN
FB G
FB R
VID 0
VID 1
VID 2
VID 3
VID 4
PG O O D
O S C / I N H
S GN D
VC C D R
32 k
V C C D R
V C C
L
OGI
C A
N
D
P
R
OT
E
C
T
I
ON
S
C H 2 OC P
P W M2
CU
RR
E
N
T
CO
RR
E
C
T
I
O
N
CH2
O CP
CU R REN T
REA DIN G
LO
G
I
C
P
W
M
A
D
AP
T
I
VE
A
N
T
I
C
R
O
S
S
CO
ND
UC
T
I
O
N
CU R REN T
REA DIN G
CU R REN T
REA DIN G
I
FB
TO TA L
C U R R EN T
C
U
RRE
NT
AVG
CH1
O CP
D A C
D IGITAL
SOF T-START
LO
G
I
C
P
W
M
AD
A
P
T
I
VE
A
N
T
I
CR
O
S
S
C
O
ND
U
C
T
I
O
N
LO
G
I
C
P
W
M
AD
A
P
T
I
VE
A
N
T
I
CR
O
S
S
C
O
ND
U
C
T
I
O
N
C H 1 OC P
2
PH
A
S
E
OS
C
I
L
L
A
T
OR
P W M1
CU
RR
E
N
T
CO
RR
E
C
T
I
O
N
ERR OR
A MPL IF IER
R EMO TE
BU FFE R
3 2k
3 2k
3 2k
L S
LS
H S
Vc c
H S
BO O T 1
U
GA T E1
PH AS E1
L GAT E1
ISE N1
PG N DS 1
PG N D
PG N DS 2
ISE N2
L GAT E2
PH AS E2
U GA T E2
BO O T 2
V cc
CO M P
FB
V S EN
FB G
FB R
VID 0
VID 1
VID 2
VID 3
VID 4
PG O O D
O S C / I N H
S GN D
VC C D R
32 k
V C C D R
V C C
L
OGI
C A
N
D
P
R
OT
E
C
T
I
ON
S
C H 2 OC P
P W M2
CU
RR
E
N
T
CO
RR
E
C
T
I
O
N
CH2
O CP
CU R REN T
REA DIN G
CU R REN T
REA DIN G
LO
G
I
C
P
W
M
A
D
AP
T
I
VE
A
N
T
I
C
R
O
S
S
CO
ND
UC
T
I
O
N
LO
G
I
C
P
W
M
A
D
AP
T
I
VE
A
N
T
I
C
R
O
S
S
CO
ND
UC
T
I
O
N
L6919C
2/32
ABSOLUTE MAXIMUM RATINGS
THERMAL DATA
PIN CONNECTION
Symbol
Parameter
Value
Unit
Vcc, V
CCDR
to PGND
15
V
V
BOOT
-V
PHASE
Boot Voltage
15
V
V
UGATE1
-V
PHASE1
V
UGATE2
-V
PHASE2
15
V
LGATE1, PHASE1, LGATE2, PHASE2 to PGND
-0.3 to Vcc+0.3
V
VID0 to VID4
-0.3 to 5
V
All other pins to PGND
-0.3 to 7
V
V
phase
Sustainable Peak Voltage t < 20ns @ 600kHz
26
V
Symbol
Parameter
Value
Unit
R
th j-amb
Thermal Resistance Junction to Ambient
60
C/W
T
max
Maximum junction temperature
150
C
T
storage
Storage temperature range
-40 to 150
C
T
j
Junction Temperature Range
0 to 125
C
P
MAX
Max power dissipation at T
amb
= 25C
2
W
1
3
2
4
5
6
7
8
9
18
17
16
15
19
20
10
11
12
13
14
24
23
22
21
25
26
27
28
LGATE1
VCCDR
PHASE1
FB
BOOT1
UGATE1
VSEN
VCC
SGND
COMP
ISEN1
PGNDS1
FBR
FBG
VID3
VID2
VID1
VID4
BOOT2
PGOOD
UGATE2
PHASE2
LGATE2
PGND
OSC / INH / FAULT
ISEN2
PGNDS2
VID0
L6919
C
3/32
L6919C
ELECTRICAL CHARACTERISTICS
V
CC
= 12V 10%, T
J
= 0 to 70C unless otherwise specified
Symbol
Parameter
Test Condition
Min
Typ
Max
Unit
Vcc SUPPLY CURRENT
I
CC
Vcc supply current
HGATEx and LGATEx open
V
CCDR
=V
BOOT
=12V
7.5
10
12.5
mA
I
CCDR
V
CCDR
supply current
LGATEx open; V
CCDR
=12V
2
3
4
mA
I
BOOTx
Boot supply current
HGATEx open; PHASEx to PGND
V
CC
=V
BOOT
=12V
0.5
1
1.5
mA
POWER-ON
Turn-On V
CC
threshold
V
CC
Rising; V
CCDR
=5V
8
9.2
10.4
V
Turn-Off V
CC
threshold
V
CC
Falling; V
CCDR
=5V
6.5
7.5
8.5
V
Turn-On V
CCDR
Threshold
V
CCDR
Rising
V
CC
=12V
4.2
4.4
4.6
V
Turn-Off V
CCDR
Threshold
V
CCDR
Falling
V
CC
=12V
4.0
4.2
4.4
V
OSCILLATOR/INHIBIT/FAULT
f
OSC
Initial Accuracy
OSC = OPEN
OSC = OPEN; Tj=0
C to 125
C
185
180
200
215
220
kHz
kHz
f
OSC,Rosc
Total Accuracy
R
T
to GND=74k
360
400
440
kHz
INH
Inhibit threshold
I
SINK
=5mA
0.5
V
d
MAX
Maximum duty cycle
OSC = OPEN; I
FB
= 0
75
80
%
OSC = OPEN; I
FB
= 60
A
38
46
%
Vosc
Ramp Amplitude
1.8
2
2.2
V
FAULT
Voltage at pin OSC
OVP or UVP Active
4.75
5.0
5.25
V
REFERENCE AND DAC
Output Voltage
Accuracy
VID0, VID1, VID2, VID3, VID4
see Table1;
FBR = V
OUT
; FBG = GND
-0.6
-
0.6
%
I
DAC
VID pull-up Current
VIDx = GND
4
5
6
A
VID pull-up Voltage
VIDx = OPEN
3.2
-
3.5
V
ERROR AMPLIFIER
DC Gain
80
dB
SR
Slew-Rate
COMP=10pF
15
V/
s
DIFFERENTIAL AMPLIFIER (REMOTE BUFFER)
DC Gain
1
V/V
CMRR
Common Mode Rejection Ratio
40
dB
SR
Slew Rate
VSEN=10pF
15
V/
s
L6919C
4/32
DIFFERENTIAL CURRENT SENSING
I
ISEN1
,
I
ISEN2
Bias Current
I
LOAD
= 0
45
50
55
A
I
PGNDSx
Bias Current
45
50
55
A
I
ISEN1
,
I
ISEN2
Bias Current at
Over Current Threshold
80
85
90
A
I
FB
Active Droop Current
I
LOAD
0%
I
LOAD
= 100%
47.5
0
50
1
52.5
A
A
GATE DRIVERS
t
RISE
HGATE
High Side
Rise Time
V
BOOTx
-V
PHASEx
=10V;
C
HGATEx
to PHASEx=3.3nF
15
30
ns
I
HGATEx
High Side
Source Current
V
BOOTx
-V
PHASEx
=10V 2
A
R
HGATEx
High Side
Sink Resistance
V
BOOTx
-V
PHASEx
=12V;
1.5
2
2.5
t
RISE
LGATE
Low Side
Rise Time
V
CCDR
=10V;
C
LGATEx
to PGNDx=5.6nF
30
55
ns
I
LGATEx
Low Side
Source Current
V
CCDR
=10V
1.8
A
R
LGATEx
Low Side
Sink Resistance
V
CCDR
=12V
0.7
1.1
1.5
PROTECTIONS
PGOOD
Upper Threshold
(V
SEN
/DAC Output)
V
SEN
Rising
108
112
116
%
PGOOD
Lower Threshold
(V
SEN
/DAC Output)
V
SEN
Falling
84
88
92
%
OVP
Over Voltage Threshold
(V
SEN
)
V
SEN
Rising
1.915
2.05
V
UVP
Under Voltage Trip
(V
SEN
/DAC Output)
V
SEN
Falling
65
70
75
%
V
PGOOD
PGOOD Voltage Low
I
PGOOD
= -4mA
0.3
0.4
0.5
V
ELECTRICAL CHARACTERISTICS (continued)
V
CC
= 12V 10%, T
J
= 0 to 70C unless otherwise specified
Symbol
Parameter
Test Condition
Min
Typ
Max
Unit
5/32
L6919C
Table 1. Voltage Identification (VID) Codes
Reference Schematic
VID4 VID3
VID2
VID1
VID0
Output
Voltage (V)
VID4 VID3
VID2
VID1
VID0
Output
Voltage (V)
0
0
0
0
0
1.550
1
0
0
0
0
1.150
0
0
0
0
1
1.525
1
0
0
0
1
1.125
0
0
0
1
0
1.500
1
0
0
1
0
1.100
0
0
0
1
1
1.475
1
0
0
1
1
1.075
0
0
1
0
0
1.450
1
0
1
0
0
1.050
0
0
1
0
1
1.425
1
0
1
0
1
1.025
0
0
1
1
0
1.400
1
0
1
1
0
1.000
0
0
1
1
1
1.375
1
0
1
1
1
0.975
0
1
0
0
0
1.350
1
1
0
0
0
0.950
0
1
0
0
1
1.325
1
1
0
0
1
0.925
0
1
0
1
0
1.300
1
1
0
1
0
0.900
0
1
0
1
1
1.275
1
1
0
1
1
0.875
0
1
1
0
0
1.250
1
1
1
0
0
0.850
0
1
1
0
1
1.225
1
1
1
0
1
0.825
0
1
1
1
0
1.200
1
1
1
1
0
0.800
0
1
1
1
1
1.175
1
1
1
1
1
Shutdown
PGOOD
PGND
PGNDS2
ISEN2
LGATE2
VSEN
FB
PHASE2
UGATE2
BOOT2
VCC
COMP
SGND
OSC / INH
VID0
VID1
VID2
VID3
VID4
PGNDS1
ISEN1
LGATE1
PHASE1
UGATE1
BOOT1
VCCDR
6
24
25
26
27
16
15
2
5
4
3
1
13
14
22
21
20
18
19
7
28
23
10
9
8
11
12
FBR
FBG
17
R
FB
R
F
C
F
Rg
Rg
LS2
HS2
L2
C
IN
C
OUT
S1
S0
S3
S2
S4
Rg
LS1
L1
HS1
Vin
GNDin
PGOOD
L6919C
LOAD
Rg
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