LTC4069-4.4 Linear Technology, LTC4069-4.4 Datasheet - Page 15

• Manufacturer Part Number: LTC4069-4.4
• Description: Standalone 750mA Li-Ion Battery Charger in 2 x 2 DFN
• Manufacturer: Linear Technology

PACKAGE DESCRIPTION
NTC Trip Point Error
When a 1% resistor is used for R
in the 40°C trip point is determined by the tolerance of
the NTC thermistor. A typical 100k NTC thermistor has
±10% tolerance. By looking up the temperature coeffi cient
of the thermistor at 40°C, the tolerance error can be
calculated in degrees centigrade. Consider the Vishay
NTHS0603N01N1003J thermistor, which has a temperature
coeffi cient of – 4%/°C at 40°C. Dividing the tolerance by
the temperature coeffi cient, ±5%/(4%/°C) = ±1.25°C, gives
the temperature error of the hot trip point.
R
R
2.50 ±0.05
NOM
1
=
=
= 604
10
1.15 ±0.05
=
8 8 8 87
3 266 0 5325
k
R
. , .
.
•
COLD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WCCD-2)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
k
⎛
⎝ ⎜
Ω
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
TOP AND BOTTOM OF PACKAGE
3 26
0.61 ±0.05
(2 SIDES)
,
.
−
604
−
0 5325
R
.
6 6 0 5325
k is
.
HOT
−
is the nearest
.
the nearest
=
1.42 ±0.05
(2 SIDES)
10
⎞
⎠ ⎟
k
• .
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
3 266 0 5325
• .
(
.
(
0.50 BSC
2 816 0 4086
2 816 0
1
1
%
%
0.25 ± 0.05
−
HOT
0.675 ±0.05
value
value
−
−
.
PACKAGE
OUTLINE
, the major error
.
.4 4 086
.
.
6-Lead Plastic DFN (2mm × 2mm)
(Reference LTC DWG # 05-08-1703)
(SEE NOTE 6)
)
TOP MARK
)
PIN 1 BAR
−
0 4086
.
0.200 REF
DC Package
The cold trip point error depends on the tolerance of the
NTC thermistor and the degree to which the ratio of its
value at 0°C and its value at 40°C varies from 6.14 to
1. Therefore, the cold trip point error can be calculated
using the tolerance, TOL, the temperature coeffi cient
of the thermistor at 0°C, TC (in %/°C), the value of the
thermistor at 0°C, R
at 40°C, R
For example, the Vishay NTHS0603N01N1003J thermistor
with a tolerance of ±5%, TC of –5%/°C and R
of 6.13, has a cold trip point error of:
Temperature Error C
Temperature Error C
0.75 ±0.05
HOT
2.00 ±0.10
(4 SIDES)
. The formula is:
0.00 – 0.05
( )
( )
COLD
° =
° =
0.56 ± 0.05
(2 SIDES)
= −
, and the value of the thermistor
0 95
⎛
⎝ ⎜
⎛
⎜ ⎜
⎝
R = 0.115
.
BOTTOM VIEW—EXPOSED PAD
+ 1
1 0 05
+
6 14
6 14
TYP
.
°
.
TOL R
C
.
, .
www.DataSheet4U.com
1.37 ±0.05
(2 SIDES)
1 05
3
LTC4069-4.4
4
•
• .
6 13 1
R
−
°
TC
6
COLD
1
C
5
HOT
0.50 BSC
0.38 ± 0.05
−
0.25 ± 0.05
PIN 1
CHAMFER OF
EXPOSED PAD
− −
⎞
⎠ ⎟
COLD
1
⎞
⎠ ⎟
• 100
15
(DC6) DFN 1103
•
/R
406944fa
100
HOT