19-0146; Rev 2; 5/94
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Info
Triple-Output Power-Supply
Controller for Notebook Computers
___________________________Features
o
o
o
o
o
Dual PWM Buck Controllers (+3.3V and +5V)
Dual PCMCIA VPP Outputs (0V/5V/12V)
Three Precision Comparators or Level Translators
95% Efficiency
420µA Quiescent Current;
70µA in Standby (linear regulators alive)
o
5.5V to 30V Input Range
o
Small SSOP Package
o
Fixed Output Voltages Available:
3.3 (standard)
3.45 (High-Speed Pentium™)
3.6 (PowerPC™)
_______________General Description
The MAX782 is a system-engineered power-supply con-
troller for notebook computers or similar battery-powered
equipment. It provides two high-performance step-down
(buck) pulse-width modulators (PWMs) for +3.3V and +5V,
and dual PCMCIA VPP outputs powered by an integral fly-
back winding controller. Other functions include dual, low-
dropout, micropower linear regulators for CMOS/RTC back-
up, and three precision low-battery-detection comparators.
High efficiency (95% at 2A; greater than 80% at loads
from 5mA to 3A) is achieved through synchronous recti-
fication and PWM operation at heavy loads, and Idle-
Mode
TM
operation at light loads. It uses physically
small components, thanks to high operating frequen-
cies (300kHz/200kHz) and a new current-mode PWM
architecture that allows for output filter capacitors as
small as 30µF per ampere of load. Line- and load-tran-
sient response are terrific, with a high 60kHz unity-gain
crossover frequency allowing 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 controller provides a low-cost,
+15V high-side output that regulates 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 synchroniz-
able oscillator for noise-sensitive applications such as
electromagnetic pen-based systems and communicat-
ing computers. The MAX782 is a monolithic BiCMOS IC
available in fine-pitch, SSOP surface-mount packages.
MAX782
______________Ordering Information
PART
MAX782CBX
MAX782RCBX
MAX782SCBX
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
36 SSOP
36 SSOP
36 SSOP
V
OUT
3.3V
3.45V
3.6V
Ordering Information continued on last page.
__________________Pin Configuration
TOP VIEW
ON3
1
D1
2
D2
3
D3
4
VH
5
Q3
6
Q2
7
Q1
8
VPPA
9
VDD
10
VPPB
11
GND
12
36
SS3
35
CS3
34
FB3
33
DH3
_______________________Applications
Notebook Computers
Portable Data Terminals
Communicating Computers
Pen-Entry Systems
MAX782
32
LX3
31
BST3
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
VPP (0V/5V/12V)
VPP (0V/5V/12V)
4
SUSPEND POWER
LOW-BATTERY WARNING
DUAL
PCMCIA
SLOTS
POWER
SECTION
µP
MEMORY
+5V
PERIPHERALS
REF
13
SYNC
14
DA1
15
DA0
16
DB1
17
DB0
18
MAX782
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
MAX782
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-D3, ON5, REF, SYNC, DA1, DA0, DB1, DB0, ON5,
SS5, CS5, FB5, 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-Q3 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) ...................941mW
Operating Temperature Ranges:
MAX782CBX/MAX782__CBX ...............................0°C to +70°C
MAX782EBX/MAX782__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.
ELECTRICAL CHARACTERISTICS
(V+ = 15V, GND = PGND = 0V, I
VL
= I
REF
= 0mA, 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)
MAX782
0mV < (CS3-FB3) < 70mV, 6V < V+ < 30V
MAX782R
(includes load and line regulation)
MAX782S
Either controller (CS_ - FB_ = 0mV to 70mV)
Either controller (V+ = 6V to 30V)
CS3-FB3 or CS5-FB5
CS5-FB5 (VDD < 13V, flyback mode)
CONDITIONS
MIN
5.5
4.80
3.17
3.32
3.46
5.08
3.35
3.50
3.65
2
0.03
100
-100
4.0
TYP
MAX
30
5.20
3.46
3.60
3.75
UNITS
V
V
V
V
V
%
%/V
mV
µA
mA
V
V
mA
µA
µA
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
VDD Off Current
PCMCIA REGULATORS
(Note 1)
80
-50
2.5
2
120
-160
6.5
Falling edge, hysteresis = 1%
Rising edge, hysteresis = 1%
VDD = 20V
VDD = 18V, ON3 = ON5 = 5V,
VPPA/B programmed to 12V with no external load
VDD = 18V, ON3 = ON5 = 5V,
VPPA/B programmed to Hi-Z or 0V
Program to 12V, 13V < VDD < 19V, 0mA < I
L
< 60mA
13
18
2
14
20
3
140
15
300
30
11.6
4.85
-0.3
12.1
5.05
12.5
5.20
0.3
35
µA
V
VPPA/VPPB Output Voltage
VPPA/VPPB Off Input Current
2
Program to 5V, 13V < VDD < 19V, 0mA < I
L
< 60mA
Program to 0V, 13V < VDD < 19V, -0.3mA < I
L
< 0.3mA
Program to Hi-Z, VDD = 19V, 0V < VPP < 12V
_______________________________________________________________________________________
Triple-Output Power-Supply
Controller for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, GND = PGND = 0V, I
VL
= I
REF
= 0mA, ON3 = ON5 = 5V, other digital input levels are 0V or +5V, T
A
= T
MIN
to T
MAX
,
unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
INTERNAL REGULATOR AND REFERENCE
VL Output Voltage
VL Fault Lockout Voltage
VL/FB5 Switchover Voltage
REF Output Voltage
REF Fault Lockout Voltage
REF Load Regulation
V+ Standby Current
Quiescent Power Consumption
(both PWM controllers on)
V+ Off Current
COMPARATORS
D1-D3 Trip Voltage
D1-D3 Input Current
Q1-Q3 Source Current
Q1-Q3 Sink Current
Q1-Q3 Output High Voltage
Q1-Q3 Output Low Voltage
Quiescent VH Current
Falling edge, hysteresis = 1%
D1 = D2 = D3 = 0V to 5V
VH = 15V, Q1-Q3 forced to 2.5V
VH = 15V, Q1-Q3 forced to 2.5V
I
SOURCE
= 5µA, VH = 3V
I
SINK
= 20µA, VH = 3V
VH = 18V, D1 = D2 = D3 = 5V, no external load
SYNC = 3.3V
SYNC = 0V or 5V
270
170
200
200
Not tested
240
SYNC = 3.3V
SYNC = 0V or 5V
ON3, ON5, DA0, DA1, DB0, DB1, SYNC
ON3, ON5, DA0, DA1, DB0, DB1
SYNC
ON3, ON5, DA0, DA1, DB0, DB1, V
IN
= 0V or 5V
DL3, DL5 forced to 2V
BST3-LX3 = BST5-LX5 = 4.5V, DH3, DH5 forced to 2V
High or low
High or low, BST3-LX3 = BST5-LX5 = 4.5V
1
1
7
7
2.4
VL-0.5
±1
89
92
92
95
0.8
200
350
6
300
200
12
200
VH-0.5
0.4
10
330
230
20
500
1.61
1.69
±100
30
1000
V
nA
µA
µA
V
V
µA
ON5 = ON3 = 0V, 5.5V < V+ < 30V, 0mA < I
L
< 25mA
Falling edge, hysteresis = 1%
Rising edge of FB5, hysteresis = 1%
No external load (Note 2)
Falling edge
0mA < I
L
< 5mA
D1 = D2 = D3 = ON3 = ON5 = DA0 = DA1 = DB0 =
DB1 = 0V, V+ = 30V
D1 = D2 = D3 = DA0 = DA1 = DB0 = DB1 = 0V,
FB5 = CS5 = 5.25V, FB3 = CS3 = 3.5V
FB5 = CS5 = 5.25V, VL switched over to FB5
4.5
3.6
4.2
3.24
2.4
30
70
6.0
30
5.5
4.2
4.7
3.36
3.2
75
110
8.6
60
V
V
V
V
V
mV
µA
mW
µA
MAX782
OSCILLATOR AND INPUTS/OUTPUTS
Oscillator Frequency
SYNC High Pulse Width
SYNC Low Pulse Width
SYNC Rise/Fall Time
Oscillator SYNC Range
Maximum Duty Cycle
Input Low Voltage
Input High Voltage
Input Current
DL3/DL5 Sink/Source Current
DH3/DH5 Sink/Source Current
DL3/DL5 On Resistance
DH3/DH5 On Resistance
kHz
ns
ns
ns
kHz
%
V
V
µA
A
A
Ω
Ω
Note 1:
Output current is further limited by maximum allowable package power dissipation.
Note 2:
Since the reference uses VL as its supply, V+ line regulation error is insignificant.
_______________________________________________________________________________________
3
Triple-Output Power-Supply
Controller for Notebook Computers
MAX782
__________________________________________Typical Operating Characteristics
(Circuit of Figure 1, Transpower transformer type TTI5870, T
A
= +25°C, unless otherwise noted.)
EFFICIENCY vs.
+5V OUTPUT CURRENT, 200kHz
100
V
IN
= 10V
EFFICIENCY (%)
EFFICIENCY (%)
90
V
IN
= 15V
90
V
IN
= 6V
100
EFFICIENCY vs.
+5V OUTPUT CURRENT, 300kHz
I
DD
= 0mA
+3.3V OFF
I
DD
OUTPUT CURRENT vs. INPUT VOLTAGE
COILTRONIX CTX03-12062 TRANSFORMER
10
+3V LOAD = 0mA
R
SENSE
= 0.020Ω
V
IN
= 6V
I
DD
LOAD CURRENT (A)
1
+5V LOAD = 0A-1A
V
IN
= 15V
V
IN
= 30V
+5V LOAD = 3A
0.1
80
COMPONENTS,
OF TABLE 5. SYNC = 0V,
+3.3V OFF, I
DD
= 0mA
0.01
0.1
1
10
80
70
0.001
70
0.001
0.01
0.01
0.1
1
10
5
10
15
20
25
30
+5V OUTPUT CURRENT (A)
INPUT VOLTAGE (V)
+5V OUTPUT CURRENT (A)
EFFICIENCY vs.
+3.3V OUTPUT CURRENT, 200kHz
100
+5V ON, +5V LOAD = 0mA
I
DD
= 0mA,
COMPONENTS OF TABLE 5
EFFICIENCY (%)
EFFICIENCY (%)
90
V
IN
= 6V
V
IN
= 10V
V
IN
= 15V
90
100
EFFICIENCY vs.
+3.3V OUTPUT CURRENT, 300kHz
I
DD
= 0mA
+5V ON
+5V LOAD = 0mA
10000
V
IN
= 6V
INPUT CURRENT (µA)
1000
QUIESCENT INPUT CURRENT vs.
INPUT VOLTAGE
+3.3V LOAD = +5V LOAD = 0mA
V
IN
= 15V
V
IN
= 30V
80
+5V, +3V ON
80
100
+5V, +3V OFF
70
0.001
0.01
0.1
1
10
70
0.001
10
0.01
0.1
1
10
0
5
10
15
20
25
30
+3.3V OUTPUT CURRENT (A)
INPUT VOLTAGE (V)
+3.3V OUTPUT CURRENT (A)
+5V OUTPUT CURRENT vs.
MINIMUM INPUT VOLTAGE, 300kHz
9
MINIMUM INPUT VOLTAGE (V)
I
DD
= 300mA
8
MINIMUM INPUT VOLTAGE (V)
9
+5V OUTPUT CURRENT vs.
MINIMUM INPUT VOLTAGE, 200kHz
COMPONENTS OF TABLE 4,
SYNC = 0V
I
DD
= 300mA
1000
SWITCHING FREQUENCY (kHz)
SWITCHING FREQUENCY vs.
LOAD CURRENT
CIRCUIT OF FIGURE 1,
SYNC = REF (300kHz)
ON3 = ON5 = 5V
+5V, V
IN
= 7.5V
8
100
7
I
DD
= 140mA
7
I
DD
= 140mA
10
+5V, V
IN
= 30V
6
I
DD
= 60mA
I
DD
= 0mA
6
I
DD
= 60mA
I
DD
= 0mA
1
+3.3V, V
IN
= 7.5V
5
0.01
5
0.1
1
10
0.01
0.1
1
10
+5V OUTPUT CURRENT (A)
+5V LOAD CURRENT (A)
0.1
100µA
1mA
10mA
100mA
1A
LOAD CURRENT
4
_______________________________________________________________________________________
Triple-Output Power-Supply
Controller for Notebook Computers
_____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 1, Transpower transformer type TTI5870, T
A
= +25°C, unless otherwise noted.)
MAX782
PULSE-WIDTH MODULATION MODE WAVEFORMS
IDLE-MODE WAVEFORMS
LX VOLTAGE
10V/div
LX VOLTAGE
10V/div
+5V OUTPUT
VOLTAGE
50mV/div
+5V OUTPUT
VOLTAGE
50mV/div
HORIZONTAL = 500ns/div
+5V OUTPUT CURRENT = 1A
INPUT VOLTAGE = 16V
HORIZONTAL = 5µs/div
+5V OUTPUT CURRENT = 42mA
INPUT VOLTAGE = 16V
+5V LOAD-TRANSIENT RESPONSE
+3.3V LOAD-TRANSIENT RESPONSE
3A
0A
LOAD CURRENT
3A
0A
LOAD CURRENT
+5V OUTPUT
50mV/div
+3.3V OUTPUT
50mV/div
HORIZONTAL = 200µs/div
V
IN
= 15V
HORIZONTAL = 200µs/div
V
IN
= 15V
_______________________________________________________________________________________
5
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