19-0045; Rev 1; 5/94
Kit
tion cluded
lua
Eva tion In
rma
Info
Triple-Output Power-Supply Controller
for Notebook Computers
____________________________Features
o
o
o
o
o
o
o
Dual PWM Buck Controllers (+3.3V and +5V)
Dual PCMCIA VPP Outputs (0V/3.3V/5V/12V)
Two Precision Comparators or Level Translators
Power-Ready Status Output (
RDY5
)
95% Efficiency
Optimized for 6-Cell Applications
420µA Quiescent Current;
70µA in Standby (linear regulators alive)
25µA Shutdown Current
o
5.5V to 30V Input Range
o
Small SSOP Package
o
Fixed Output Voltages Available:
3.3V (standard)
3.45V (High-Speed Pentium™)
3.6V (PowerPC™)
_______________General Description
The MAX783 is a system-engineered power-supply controller
for notebook computers or similar battery-powered equipment.
It provides two high-performance step-down (buck) pulse-
width modulators (PWMs) for +3.3V/+5V and dual PCMCIA
VPP outputs powered by an integral flyback winding controller.
Other functions include dual, low-dropout, micropower linear
regulators for CMOS/RTC back up, and two precision low-
battery-detection comparators.
High efficiency (95% at 2A, greater than 80% at loads from
5mA to 3A) is achieved through synchronous rectification
and PWM operation at heavy loads, and Idle-Mode
TM
oper-
ation at light loads. The MAX783 uses physically small
components, thanks to high operating frequencies
(300kHz/200kHz) and a new current-mode PWM architec-
ture that allows for output filter capacitors as small as 30µF
per ampere of load. Line- and load-transient responses
are terrific, with a high 60kHz unity-gain crossover frequen-
cy that allows output transients to be corrected within four
or five clock cycles. Low system cost is achieved through
a high level of integration and the use of low-cost external
N-channel MOSFETs. The integral flyback winding con-
troller provides a low-cost, +15V high-side output that regu-
lates even in the absence of a load on the main output.
Other features include low-noise, fixed-frequency PWM
operation at moderate to heavy loads and a synchronizable
oscillator for noise-sensitive applications such as electro-
magnetic pen-based systems and communicating comput-
ers. The MAX783 is similar to the MAX782, except the fly-
back winding is on the 3.3V inductor instead of the 5V
inductor, the VPP outputs can be optionally programmed to
3.3V, and the device may be completely shut down.
MAX783
______________Ordering Information
PART
MAX783CBX
MAX783RCBX
TEMP. RANGE
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
36 SSOP
36 SSOP
V
OUT
3.3V
3.45V
Ordering Information continued on last page.
__________________Pin Configuration
TOP VIEW
ON3
1
SHDN
2
D1
3
D2
4
VH
5
Q2
6
Q1
7
RDY5
8
VPPA
9
VDD
10
VPPB
11
36
SS3
35
CS3
34
FB3
33
DH3
32
LX3
31
BST3
________________________Applications
Notebook Computers
Portable Data Terminals
Communicating Computers
Pen-Entry Systems
MAX783
30
DL3
29
V+
28
VL
27
FB5
26
PGND
25
DL5
24
BST5
23
LX5
22
DH5
21
CS5
20
SS5
19
ON5
_______Typical Application Diagram
+3.3V
5.5V
TO
30V
VPP
CONTROL
ON3
ON5
SYNC
SHDN
4
SUSPEND POWER
POWER
SECTION
µP
MEMORY
+5V
PERIPHERALS
GND
12
REF
13
SYNC
14
DA1
15
DA0
16
MAX783
LOW-BATTERY WARNING
VPP (0V/3.3V/5V/12V)
VPP (0V/3.3V/5V/12V)
DUAL
PCMCIA
SLOTS
DB1
17
DB0
18
SSOP
™
Idle-Mode is a trademark of Maxim Integrated Products. Pentium is a trademark of Intel. PowerPC is a trademark of IBM.
________________________________________________________________
Maxim Integrated Products
1
Call toll free 1-800-998-8800 for free samples or literature.
Triple-Output Power-Supply Controller
for Notebook Computers
MAX783
ABSOLUTE MAXIMUM RATINGS
V+ to GND .................................................................-0.3V, +36V
PGND to GND........................................................................±2V
VL to GND ...................................................................-0.3V, +7V
BST3, BST5 to GND ..................................................-0.3V, +36V
LX3 to BST3.................................................................-7V, +0.3V
LX5 to BST5.................................................................-7V, +0.3V
Inputs/Outputs to GND
— —
— –
(D1, D2, SHDN, ON5, REF, SYNC, DA1, DA0, DB1, DB0, ON5,
——
—–
SS5, CS5, FB5, RDY5, CS3, FB3, SS3, ON3).-0.3V, (VL + 0.3V)
VDD to GND.................................................................-0.3V, 20V
VPPA, VPPB to GND.....................................-0.3V, (VDD + 0.3V)
VH to GND ...................................................................-0.3V, 20V
Q1, Q2 to GND................................................-0.3V, (VH + 0.3V)
DL3, DL5 to PGND..........................................-0.3V , (VL + 0.3V)
DH3 to LX3 ..................................................-0.3V, (BST3 + 0.3V)
DH5 to LX5 ..................................................-0.3V, (BST5 + 0.3V)
REF, VL, VPP Short to GND........................................Momentary
REF Current.........................................................................20mA
VL Current ...........................................................................50mA
VPPA, VPPB Current .........................................................100mA
Continuous Power Dissipation (T
A
= +70°C)
SSOP (derate 11.76mW/°C above +70°C) ...................762mW
Operating Temperature Ranges:
MAX783CBX/MAX783_CBX.................................0°C to +70°C
MAX783EBX/MAX783_EBX ..............................-40°C to +85°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
———–
(V+ = 15V, GND = PGND = 0V, I
VL
= I
REF
= 0mA, S H D N = ON3 = ON5 = 5V, other digital input levels are 0V or +5V,
T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
3.3V AND 5V STEP-DOWN CONTROLLERS
Input Supply Range
FB5 Output Voltage
0mV < (CS5-FB5) < 70mV, 6V < V + < 30V
(includes load and line regulation)
0mV < (CS3-FB3) < 70mV, 6V < V + < 30V
(includes load and line regulation)
Either controller (0mV to 70mV)
Either controller (6V to 30V)
CS3-FB3 or CS5-FB5
CS3-FB3 (VDD < 13V, flyback mode)
80
-50
2.5
2
13
18
2
MAX783
MAX783R
MAX783S
CONDITIONS
MIN
5.5
4.80
3.17
3.32
3.46
5.08
3.35
3.50
3.65
2.5
0.03
100
-100
4.0
TYP
MAX
30
5.20
3.46
3.60
3.75
UNITS
V
V
ELECTRICAL CHARACTERISTICS
FB3 Output Voltage
Load Regulation
Line Regulation
Current-Limit Voltage
SS3/SS5 Source Current
SS3/SS5 Fault Sink Current
15V FLYBACK CONTROLLER
VDD Regulation Setpoint
VDD Shunt Setpoint
VDD Shunt Current
Quiescent VDD Current
Off VDD Current
PCMCIA REGULATORS (Note 1)
V
%
%/V
120
-160
6.5
mV
µA
mA
V
V
mA
µA
µA
Falling edge, hysteresis = 1%
Rising edge, hysteresis = 1%
VDD = 20V
VDD = 18V, ON3 = ON5 = 5V, VPPA/VPPB programmed to
12V with no external load
VDD = 18V, ON3 = ON5 = 5V, VPPA/VPPB programmed to
0V
Program to 12V, 13V < VDD < 19V, 0mA < I
L
< 60mA
Program to 5V, 13V < VDD < 19V, 0mA < I
L
< 60mA
Program to 3.3V, 13V < VDD < 19V, 0mA < I
L
< 60mA
Program to 0V, 13V < VDD < 19V, 0mA < I
L
< 0.3mA
14
20
3
140
15
300
30
VPPA/VPPB Output Voltage
11.60
4.85
3.17
-0.30
12.10
5.05
3.30
12.50
5.20
3.43
0.30
V
2
_______________________________________________________________________________________
Triple-Output Power-Supply Controller
for Notebook Computers
———–
(V+ = 15V, GND = PGND = 0V, I
VL
= I
REF
= 0mA, S H D N = ON3 = ON5 = 5V, other digital input levels are 0V or +5V,
T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
CONDITIONS
INTERNAL REGULATOR AND REFERENCE
VL Output Voltage
ON5 = ON3 = 0V, 5.5V < V+ < 30V, 0mA < I
L
< 25mA
VL Fault Lockout Voltage
Falling edge, hysteresis = 1%
VL/FB5 Switchover Voltage
Rising edge of FB5, hysteresis = 1%
——
—–
(also RDY5 Trip Voltage)
REF Output Voltage
No external load (Note 2)
REF Fault Lockout Voltage
Falling edge
REF Load Regulation
0mA < I
L
< 5mA (Note 3)
–— –
— —
SHDN = D1 = D2 = ON3 = ON5 = DA0 = DA1 = DB0 =
Shutdown V+ Current
DB1 = 0V, V+ = 30V
D1 = D2 = ON3 = ON5 = DA0 = DA1 = DB0 = DB1 = 0V,
Standby V+ Current
V+ = 30V
Quiescent Power Consumption
D1 = D2 = D3 = DA0 = DA1 = DB0 = DB1 = 0V,
(both controllers on)
FB5 = CS5 = 5.25V, FB3 = CS3 = 3.5V
Off V+ Current
FB5 = CS5 = 5.25V, VL switched over to FB5
COMPARATORS
D1, D2 Trip Voltage
Falling edge, hysteresis = 1%
D1, D2 Input Current
D1 = D2 = 0V to 5V
——
—–
Q1, Q2 RDY5 Source Current
VH = 15V, V
OUT
= 2.5V
——
—–
Q1, Q2 RDY5 Sink Current
VH = 15V, V
OUT
2.5V
——
—–
Q1, Q2, RDY5 Output High Voltage I
SOURCE
= 5µA, VH = 3V
——
—–
Q1, Q2, RDY5 Output Low Voltage I
SINK
= 20µA, VH = 3V
Quiescent VH Current
VH = 18V, D1 = D2 = 5V, no external load
OSCILLATOR AND INPUTS/OUTPUTS
SYNC = 3.3V
Oscillator Frequency
SYNC = 0V or 5V
SYNC High Pulse Width
SYNC Low Pulse Width
SYNC Rise/Fall Time
Not tested
Oscillator SYNC Range
SYNC = 3.3V
Maximum Duty Cycle
SYNC = 0V or 5V
— —
— –
Input Low Voltage
SHDN, ON3, ON5, DA0, DA1, DB0, DB1, SYNC
— —
— –
SHDN, ON3, ON5, DA0, DA1, DB0, DB1
Input High Voltage
SYNC
— —
— –
Input Current
SHDN, ON3, ON5, DA0, DA1, DB0, DB1, V
IN
= 0V or 5V
MIN
4.5
3.6
4.2
3.24
2.4
30
25
70
5.2
30
1.61
12
200
VH - 0.5
0.4
4
270
170
200
200
240
89
92
2.4
VL - 0.5
±1
300
200
10
330
230
20
500
TYP
MAX
5.5
4.2
4.7
3.36
3.2
75
40
110
8.6
60
1.69
±100
30
1000
UNITS
V
V
V
V
V
mV
µA
µA
mW
µA
V
nA
µA
µA
V
V
µA
ELECTRICAL CHARACTERISTICS (continued)
MAX783
kHz
ns
ns
ns
kHz
%
200
350
92
95
0.8
V
V
µA
_______________________________________________________________________________________
3
Triple-Output Power-Supply Controller
for Notebook Computers
MAX783
———–
(V+ = 15V, GND = PGND = 0V, I
VL
= I
REF
= 0mA, S H D N = ON3 = ON5 = 5V, other digital input levels are 0V or +5V,
T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
DL3/DL5 Sink/Source Current
DH3/DH5 Sink/Source Current
DL3/DL5 On-Resistance
DH3/DH5 On-Resistance
V
OUT
= 2V
BST3-LX3 = BST5-LX5 = 4.5V, V
OUT
= 2V
High or low
High or low, BST3-LX3 = BST5-LX5 = 4.5V
CONDITIONS
MIN
TYP
1
1
7
7
MAX
UNITS
A
A
Ω
Ω
ELECTRICAL CHARACTERISTICS (continued)
Note 1:
Output current is further limited by maximum allowable package power dissipation.
Note 2:
Because the reference uses VL as its supply, the REF line regulation error is insignificant.
Note 3:
The main switching outputs track the reference voltage. Loading the reference reduces the main outputs slightly according
to the closed-loop gain (AV
CL
) and the reference voltage load regulation error. AV
CL
for the +3.3V supply is unity gain.
AV
CL
for the +5V supply is 1.54.
__________________________________________Typical Operating Characteristics
(Circuit of Figure 1, Transpower TTI5902 transformer, T
A
= +25°C, unless otherwise noted.)
EFFICIENCY vs.
+5V OUTPUT CURRENT
V+ = 6V
V+ = 15V
EFFICIENCY (%)
MAX183 5
EFFICIENCY vs.
+3.3V OUTPUT CURRENT
MAX183 6
100
100
V+ = 6V
90
V+ = 15V
80
MAXIMUM +15V VDD OUTPUT CURRENT vs.
SUPPLY VOLTAGE
500
MAXIMUM +15V LOAD CURRENT (mA)
VDD
>
+13V
+3.3V REGULATING
400
+3.3V LOAD = 0A
300
+3.3V LOAD = 3A
90
EFFICIENCY (%)
80
70
N1-N4 = IRF7101
ON3 = LOW
F = 200kHz
70
N1-N4 = IRF7101
ON3 = ON5 = HIGH
F = 200kHz
200
60
60
100
50
1m
10m
100m
1
10
50
1m
10m
100m
1
10
0
0
5
10
15
20
SUPPLY VOLTAGE (V)
+5V OUTPUT CURRENT (A)
+3.3V OUTPUT CURRENT (A)
QUIESCENT SUPPLY CURRENT vs.
SUPPLY VOLTAGE
14
QUIESCENT SUPPLY CURRENT (mA)
STANDBY SUPPLY CURRENT (mA)
2.5
STANDBY SUPPLY CURRENT vs.
SUPPLY VOLTAGE
13
ON3 = ON5 = HIGH
2
2.0
1.5
ON3 = ON5 = 0V
1.0
1
0.5
0
0
6
12
18
24
30
SUPPLY VOLTAGE (V)
0
0
6
12
18
SUPPLY VOLTAGE (V)
24
30
4
_______________________________________________________________________________________
Triple-Output Power-Supply Controller
for Notebook Computers
____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 1, Transpower TTI5902 transformer, T
A
= +25°C, unless otherwise noted.)
SHUTDOWN SUPPLY CURRENT vs.
SUPPLY VOLTAGE
500
MINIMUM VIN TO VOUT DIFFERENTIAL (V)
SHUTDOWN SUPPLY CURRENT (µA)
1.0
SWITCHING FREQUENCY (kHz)
MAX783
MINIMUM VIN TO VOUT DIFFERENTIAL
vs. +5V OUTPUT CURRENT
1000
SWITCHING FREQUENCY vs.
LOAD CURRENT
SYNC = REF (300kHz)
ON3 = ON5 = HIGH
100
+5V, V
IN
= 7.5V
400
0.8
300kHz
300
SHDN = 0V
200
0.6
10
+5V, V
IN
= 30V
0.4
200kHz
+5V OUTPUT
STILL REGULATING
1
+3.3V, V
IN
= 7.5V
100
0.2
0
0
6
12
18
24
SUPPLY VOLTAGE (V)
30
0
1m
10m
100m
1
10
+5V OUTPUT CURRENT (A)
0.1
100µ
1m
10m
100m
1
LOAD CURRENT (A)
PULSE-WIDTH MODULATION MODE WAVEFORMS
IDLE-MODE WAVEFORMS
LX VOLTAGE
10V/div
+5V OUTPUT
50mV/div
+5V OUTPUT
VOLTAGE
50mV/div
2V/div
500ns/div
I
LOAD
= 1A
V
IN
= 16V
I
LOAD
= 100mA
V
IN
= 10V
200µs/div
_______________________________________________________________________________________
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