SP6641BEK-5-0/TR Exar Corporation, SP6641BEK-5-0/TR Datasheet - Page 9

• Manufacturer Part Number: SP6641BEK-5-0/TR
• Description: 500mA Alkaline DC/DC Boost Regulator
• Manufacturer: Exar Corporation

Specifications of SP6641BEK-5-0/TR

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

APPLICATION INFORMATION: continued
Maximum Startup Current
It should be noted that for low input voltages the
SP6641 startup circuit can not support large
load currents at startup. In startup the SP6641
needs to boost the output from zero volts using
a charge pump which has a limited current
capacity. Once the output is greater than 1.7 to
1.9V the operate circuit takes over and the
SP6641 can supply much more current. Curves
of maximum resistive load current in startup for
the SP6641A and SP6641B are shown in Fig-
ures 13 & 14 and can be compared with Figure
2, maximum load current in operation. Also,
Table 2 provides SP6641A 3.3V resistive load
current in startup for some low cost 1812 size
chip inductors.
TABLE 1. COMPONENT SELECTION
Note: Components highlighted in bold are those used on the SP6641A or SP6641B Evaluation Board.
Rev. 5/26/05, *Patent Pending
Sipex
Part Number
SP6641A Ipk = .33A
SP6641A Ipk = .33A
SP6641A Ipk = .33A
SP6641A Ipk = .33A
SP6641B Ipk = 1A
SP6641B Ipk = 1A
SP6641B Ipk = 1A
SP6641B Ipk = 1A
SP6641B Ipk = 1A
Sipex
Part Number
SP6641A Ipk = .33A
SP6641B Ipk = 1A
SP6641B Ipk = 1A
Sipex
Part Number
SP6641A Ipk = .33A
SP6641B Ipk = 1A
Capacitance
Inductance
STMicro STPS0520Z
Zetex ZCHS2000
(µH)
(µF)
100
100
22
22
22
22
10
10
10
22
22
22
Manufacturer/
Part Number
Murata LQH55DN100M01 0.077
Murata LQH55DN220M01 0.160
Sumida CDRH5D28-220
Sumida CDRH5D28-100
Sumida CDRH6D28-220
Murata LQH43C220K04
TDK C3225X5R0J226M 0.010
Coilcraft DO1608C-223
Coilcraft DO1608C-103
SP6641A/6641B 500mA Alkaline DC/DC Boost Regulator in SOT-23
TDK NLC453232T-220
SANYO 10TPA100M
SANYO 16SA100M
Manufacturer/
CAPACITORS - SURFACE MOUNT & THRU-HOLE
Manufacturer/
Part Number
Part Number
INDUCTORS - SURFACE MOUNT
SCHOTTKY DIODE - SURFACE MOUNT
VF @ IF
0.39
0.42
(V)
Diode Specification
0.080
0.030
(max)
Series R
ESR
0.095
0.370
0.900
0.600
0.065
0.160
0.128
(Ω)
(Ω)
IF(AV)
0.50
2.00
(A)
@ 45°C (A)
Current
9
Ripple
4.00
1.20
2.70
0.90
0.70
0.37
0.42
1.30
1.10
1.70
1.20
1.20
Isat
(A)
Capacitor Specification
Inductor Specification
From the curves in Figures 13 and 14, you can
see that for low input voltages, the 22µH induc-
tor has more current capacity at startup than the
10µH inductor, due to more energy per charge
cycle in the relationship
applications, 22µH is recommended for more
startup current than 10µH.
For 1-cell battery applications, it is recommended
to apply any large load current after the SP6641
has started up, typically in a few millisecs. This
is typically not a problem in many applications
where the load is a processor whose load current
is low until the processor voltage comes up.
3.9x1.7x1.3
Size LxWxH
3x3x1.4
8Dx10L
6.6x4.5x2.9
4.4x3.2x3.2
4.5x3.2x2.6
6.6x4.5x2.9
LxWxH
Size LxWxH
5.7x5.5x3
5.7x5.5x3
1210
7343
6.7x6.5x3
(mm)
(mm)
Size
5x5x4.7
5x5x4.7
(mm)
Voltage
16.0
6.3
6.3
(V)
Reverse V
Unshielded Ferrite Core
Unshielded Ferrite Core
Unshielded Ferrite Core
Unshielded Ferrite Core
Unshielded Ferrite Core
Unshielded Ferrite Core
Shielded Ferrite Core
Shielded Ferrite Core
(V)
Shielded Ferrite Core
20
40
SMT POSCAP Tant. www.sanyovideo.com
Thru-hole OS-CON
SMT X5R Cer.
Capacitor
Inductor
Type
Type
SOD-123
SOT23-6
Package
© Copyright 2002 Sipex Corporation
Type
1
/
2
LI
2
. Thus for 1 cell
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Manufacturer
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Manufacturer
Website
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