S-8540A15FN-IAAT2Z Datasheet, PDF (7/36 Pages) Seiko Instruments Inc – SWITCHABLE SWITCHING REGULATOR CONTROLLER

STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.0_01
S-8540/8541 Series
 Electrical Characteristics
1. S-8540/8541 Series A, C types
Table 5
(Ta = 25 °C, unless otherwise specified)
Measure-
Parameter
Symbol
Conditions
Min.
Typ. Max. Units ment
Circuit
Output voltage ^*1
Input voltage
Current consumption 1
VOUT (E)
VIN = VOUT (S) × 1.5
IOUT = 120 mA
VOUT (S)
× 0.980
VOUT (S)
VOUT (S)
× 1.020
V
2
VIN
−
2.5
−
10.0
V
1
ISS1
VIN = VOUT (S) × 1.5
100 % duty ratio
S-8540/8541Axx
S-8540/8541Cxx
−
−
180
140
300
240
μA
1
Current consumption
during shutdown
EXT pin output current
Line regulation
Load regulation
Output voltage temperature
coefficient
ISSS
IEXTH
IEXTL
ΔVOUT1
ΔVOUT2
ΔV_OUT
ΔTa • V_OUT
VON/OFF = 0 V
VOUT = VOUT (S) × 0.95
VIN = 10 V, VEXT = VIN − 0.2 V
VIN = 10 V, VEXT = 0.2 V
VOUT (S) × 1.1 ≤ VIN ≤ 10 V, IOUT = 120 mA
VIN = VOUT (S) × 1.5, 10 μA ≤ IOUT ≤ 150 mA
VIN = VOUT (S) × 1.5, IOUT = 120 mA
− 40 ≤ Ta ≤ + 85 °C
−
−
1.0
μA
1
− 32
− 48
−
mA
1
45
66
−
mA
1
−
30
60
mV
2
−
30
60
mV
2
−
± 100
−
ppm/
°C
2
Oscillation frequency
fOSC
Measure waveform at the EXT S-8540/8541Axx
pin.
S-8540/8541Cxx
510
255
600
300
690
345
kHz
2
Maximum duty ratio
MaxDuty Measure waveform at the EXT pin.
100
−
−
%
2
PWM/PFM-control switch
duty ratio ^*2
PFMDuty VIN = VOUT (S) × 1.5, no load
19
29
39
%
2
Current limit detection
voltage
VSENSE
VIN = VOUT (S) × 1.5,
Measure waveform at the EXT pin.
100
125
150
mV
1
SENSE pin input current
ISENSE
VIN = VOUT (S) × 1.5, VSENSE = VIN − 0.1 V
6.7
11.2 16.8 μA
1
Shutdown pin
VSH
VIN = VOUT (S) × 1.5, Judge VOUT(S) × 0.98.
2.3
−
−
V
2
input voltage
VSL
VIN = VOUT (S) × 1.5, Judge CVREF pin "L".
−
−
0.3
V
1
Shutdown pin
ISH
VIN = VOUT (S) × 1.5, VON/OFF = VOUT
− 0.1
−
0.1
μA
1
input leakage current
ISL
VIN = VOUT (S) × 1.5, VON/OFF = 0 V
− 0.1
−
0.1
μA
1
Soft-start time
tSS
Time until VOUT (E) reaches 90% or higher of the VOUT(S) 7.0
12.0 17.0 ms
2
Efficiency
EFFI
−
−
90
−
%
2
External components
Coil (L)
:Sumida Corporation. CDRH6D28-100
Diode (SD)
:Matsushita Electric Inducstrial Co., Ltd. MA2Q737 (Schottky diode)
Output capacitor (COUT) :Nichicon Corporation F93 (16 V, 47 μF, tantalum)
Input capacitor (CIN)
Transistor (PSW)
:Nichicon Corporation F93 (16 V, 47 μF, tantalum)
:Toshiba Corporation 2SA1213
Base resistor (Rb)
Base capacitor (Cb)
:100 mΩ
:2200 pF
CVL
:1.0 μF
CSS
:0.047 μF
RSS
:220 kΩ
RSENSE
:100 mΩ
Condition: Recommended parts are used unless otherwise specified.
VIN =VOUT (S) ×1.5 V, IOUT = 120 mA (When VOUT (S) ≤ 1.6 V, then VIN = 2.5 V)
*1. VOUT (S) : Specified output voltage value, VOUT (E) : Actual output voltage value
*2. Applied to the S-8541 series only
Caution 1. Line regulation and load regulation may change greatly due to GND wiring when VIN is high.
2. In the S-8540 series (PWM control), a state in which the duty ratio 0% continues for several
clocks may occur when the input voltage is high and the output current is low. In this case,
the operation changes to the pseudo PFM mode, but the ripple voltage hardly increases.
7