Rev.1.0
_00
HIGH RIPPLE-REJECTION WLP PACKAGE
LOW DROPOUT CMOS VOLTAGE REGULATOR
S-L2985 Series
Seiko Instruments Inc.
1
The S-L2985 Series is a positive voltage regulator
with a low dropout voltage, high output voltage
accuracy, and low current consumption developed
based on CMOS technology.
A built-in low on-resistance transistor provides a
low dropout voltage and large output current, and
a built-in overcurrent protector prevents the load
current from exceeding the current capacitance of
the output transistor. An ON/OFF circuit ensures a
long battery life. Compared with the voltage
regulators using the conventional CMOS process,
a larger variety of capacitors are available,
including small ceramic capacitors.
A super-small
WLP-4B package realizes high-density mounting.
Features
Output voltage:
1.5 V to 5.5 V, selectable in 0.1 V steps.
High-accuracy output voltage:
1.0%
Low dropout voltage:
190 mV typ. (3.0 V output product, I
OUT
= 100 mA)
Low current consumption:
During operation: 50
A typ., 90 A max.
During shutdown: 0.1
A typ., 1.0 A max.
High peak current capability:
150 mA output is possible (@ V
IN
V
OUT(S)
+ 1.0 V)
*1
Built-in ON/OFF circuit:
Ensures long battery life.
Low ESR capacitor can be used: A ceramic capacitor of 0.47 F or more can be used for the output
capacitor.
High ripple rejection:
80 dB typ. (@ 1.0 kHz)
Built-in overcurrent protector:
Overcurrent of output transistor can be restricted.
Super-small package:
WLP-4B
*1. Attention should be paid to the power dissipation of the package when the output current is large.
Applications
Power supply for battery-powered devices
Power supply for personal communication devices
Power supply for home electric/electronic appliances
Power supply for cellular phones
Package
WLP-4B
(Package drawing code: HB004-A)
HIGH RIPPLE-REJECTION WLP PACKAGE LOW DROPOUT CMOS VOLTAGE REGULATOR
Rev.1.0
_00
S-L2985 Series
Seiko Instruments Inc.
3
Product Code Structure
The product types, output voltage and package name for the S-L2985 Series can be selected at the user's
request. Refer to the "Product name" for the meanings of the characters in the product name and
"Product name list" for the full product names.
1. Product name
S-L2985 x xx
-
-
-
- H4T1
Package name (abbreviation) and packing specifications
*1
H4T1: WLP-4B, Tape
Output voltage
15 to 55
(E.g., when the output voltage is 1.5 V, it is expressed as 15)
Product type
*2
A: ON/OFF pin negative logic
B: ON/OFF pin positive logic
*1. Refer to the taping specifications at the end of this book.
*2. Refer to 3. Shutdown (ON/OFF pin) under the Operation.
2. Product name list
Table 1
Output
voltage
WLP-4B
1.5V1.0% S-L2985B15-H4T1
1.8V1.0% S-L2985B18-H4T1
2.5V1.0% S-L2985B25-H4T1
2.6V1.0% S-L2985B26-H4T1
2.7V1.0% S-L2985B27-H4T1
2.8V1.0% S-L2985B28-H4T1
2.9V1.0% S-L2985B29-H4T1
3.0V1.0% S-L2985B30-H4T1
3.1V1.0% S-L2985B31-H4T1
3.2V1.0% S-L2985B32-H4T1
3.3V1.0% S-L2985B33-H4T1
3.4V1.0% S-L2985B34-H4T1
3.5V1.0% S-L2985B35-H4T1
5.0V1.0% S-L2985B50-H4T1
Remark Please contact the SII marketing department for products with an output voltage other than
those specified above or type A products.
HIGH RIPPLE-REJECTION WLP PACKAGE LOW DROPOUT CMOS VOLTAGE REGULATOR
Rev.1.0
_00
S-L2985 Series
Seiko Instruments Inc.
5
Absolute Maximum Ratings
Table 3
(Ta
= 25C unless otherwise specified)
Item
Symbol
Absolute Maximum Rating
Unit
Input voltage
V
IN
V
SS
- 0.3 to V
SS
+ 7
V
V
ON/OFF
V
SS
- 0.3 to V
IN
+ 0.3
Output voltage
V
OUT
V
SS
- 0.3 to V
IN
+ 0.3
Power dissipation
P
D
225
*1
mW
Operating ambient temperature
T
opr
-40 to +85
C
Storage ambient temperature
T
stg
-40 to +125
*1
.
Power dissipation is measured by the following SII evaluation board C
Caution The absolute maximum ratings are rated values exceeding which the product could suffer
physical damage. These values must therefore not be exceeded under any conditions.
1. Measurement Conditions(Used the SII evaluation board C)
(1) Measurement Enviroment
: Mounted on board (with no wind)
(2) Board Material
: FR-4 (4-layer)
(3) Board Size
: 40 mm
40 mm1.0 mm
2. Measurement
Result
Power dissipation
: 225 mW
0
Po
w
e
r dissi
p
a
tion
P
D
(m
W
)
Ambient temperature Ta (
C)
100
200
300
0
50
100
150
Figure 3 Power dissipation of package
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