MAX783 Datasheet, PDF (1/28 Pages) Maxim Integrated Products – Triple-Output Power-Supply Controller for Notebook Computers

19-0045; Rev 1; 5/94
Triple-Output _{InfEorvmalautaiotinonInKcliut} ^ded Power-Supply Controller
for Notebook Computers
_______________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.
____________________________Features
o Dual PWM Buck Controllers (+3.3V and +5V)
o Dual PCMCIA VPP Outputs (0V/3.3V/5V/12V)
o Two Precision Comparators or Level Translators
o Power-Ready Status Output (RDY5)
o 95% Efficiency
o Optimized for 6-Cell Applications
o 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™)
______________Ordering Information
PART
MAX783CBX
MAX783RCBX
TEMP. RANGE
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
36 SSOP
36 SSOP
VOUT
3.3V
3.45V
Ordering Information continued on last page.
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.
________________________Applications
Notebook Computers
Portable Data Terminals
Communicating Computers
Pen-Entry Systems
__________________Pin Configuration
TOP VIEW
ON3 1
SHDN 2
D1 3
D2 4
VH 5
Q2 ₆
Q1 7
RDY5 8
MAX783
36 _SS3
35 CS3
34 FB3
33 DH3
32 LX3
31 BST3
30 _DL3
29 V+
_______Typical Application Diagram
VPPA 9
VDD 10
28 _VL
27 _FB5
5.5V
TO
30V
VPP ⁴
CONTROL
ON3
ON5
SYNC
SHDN
MAX783
+3.3V
POWER
SECTION
µP
MEMORY
+5V PERIPHERALS
SUSPEND POWER
LOW-BATTERY WARNING
VPP (0V/3.3V/5V/12V)
VPP (0V/3.3V/5V/12V)
DUAL
PCMCIA
SLOTS
VPPB 11
GND 12
REF 13
SYNC 14
DA1 15
DA0 16
DB1 17
DB0 18
SSOP
26 _PGND
25 DL5
24 BST5
23 LX5
22 _DH5
21 CS5
20 SS5
19 ON5
™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
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