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A
ADVANCED INFORMATION
notice. Contact Fairchild Semiconductor for current information.
describes products that are in the planning or early design stage. Specifications may change in any manner without
www.fairchildsemi.com
Features
Chemistry independent charging
SMBus 2-wire serial interface controlled
Single and dual battery systems
8 bit output voltage DAC
8 bit current DAC
4 bit power DAC
6A max charging current
19V max battery voltage
24V max input voltage
6V min input voltage
3.3V,
±
1% over temperature “keep alive” precision
reference
5V keep-alive regulator controller onboard
100% maximum duty-cycle
Synchronous rectification
Voltage mode control
System soft start protects during adapter hot plug-ins
System current limit protection
Output overvoltage crowbar protection
Undervoltage (UVLO) shutdown
Charger output soft start implemented digitally
Input Isolation P-FET open with un-powered adapter
Battery backfeed prevented
Available in SSOP 24 package and TSSOP24
Optimized response for each control loop (current,
voltage and power)
90% efficiency for minimum heat dissipation
Power down driven by SMBus or by adapter not available
Controlled drive of discrete FETs minimizes switching
power dissipation
Logic signal ACAV indicates presence of AC adapter
(adjustable threshold)
Average current control
Remote sense input
Voltage feed forward
Applications
Notebooks’ fast chargers
PDAs
Hand-held portable instruments
Description
The RC5201 is a smart battery charger IC controller for Li+
and Ni based battery chemistries. The charger (slave)
together with the host controller and smart battery consti-
tutes a smart battery system that communicates via the
SMBus protocol, a two wire serial communication system.
An innovative power control loop allows operation from line
power and battery charging (with residual power) without
exceeding the max input power programmed according to
the AC adapter power rating.
Block Diagram
CompP
NC
′
21
24
14
19
20
17
15
16
18
22
23
1
2
12
4
CompV
P
COMP
+
V
I
CompI
SCL
PGND
SGND
Digital
Soft Start
I_OUT
REF
VTRIANG
P
P
D
S
I
13
H
11
L
3
3
10
I
9
B
8
V
7
P
6
D
5
5
SDA
SM_BUS
+
+
+
–
–
–
–
65-5201-03
ACAV
Vth
PSIN
IthINISO
IthILIM
+
–
RC5201
Chemistry Independent Intelligent Battery Charger
SMBus is a trademark of Intel Corporation
Rev. 0.5.7