STEP-UP, SUPER-SMALL PACKAGE, 1.2 MHz PWM/PFM SWITCHABLE SWITCHING REGULATOR
S-8363 Series Rev.2.0_00
Seiko Instruments Inc.
6
Electrical Characteristics
Table 5 Electrical Characteristics
(VIN = 1.8 V, VOUT = 3.3 V, Ta = +25°C unless otherwise specified)
Item Symbol Conditions Min. Typ. Max. Unit
Test
Circuit
Operating start voltage*1 VST IOUT = 1 mA, VOUT(S)*2 = 3.3 V ⎯ ⎯ 0.9 V 2
Operating input voltag e VIN ⎯ ⎯ ⎯ 4.5 V 2
Output voltage range VOUT(R) ⎯ 1.8 ⎯ 5.0 V 2
FB voltage VFB ⎯ 0.585 0.600 0.615 V 1
FB voltage temperature
coefficient ΔVFB
ΔTa
Ta = −40°C to +85°C ⎯ ±100 ⎯ ppm/°C1
FB pin input current IFB V
OUT = 1.8 V to 5.5 V, FB pin −0.1 ⎯ +0.1 μA 1
IIN1 ⎯ 6 15 μA 1 Current consumption dur in g
operation ISS1 During switching, at no load
VFB = VFB(S)*3 × 0.95 ⎯ 450 650 μA 1
IIN2 ⎯ 6 15 μA 1 Current consumption dur in g
switching off ISS2 During switching sto p
VFB = VFB(S)× 1.1 ⎯ 95 150 μA 1
Current consumption dur in g
power-off ISSS OFF/ONV= 0 V,
VIN = VOUT = 4.5 V ⎯ ⎯ 3.0 μA 1
Oscillation frequenc y fOSC ⎯ 1.0 1.2 1.4 MHz 2
Maximum duty ratio MaxDuty VFB = VFB(S) × 0.95 82 88 94 % 2
PWM / PFM switching dut y r atio PFMDuty ⎯ ⎯ 13 ⎯ % 2
Power MOS FET ON resistance*4 RNFET ⎯ ⎯ 0.25 ⎯ Ω 1
Power MOS FET leakage cu rrent ILSW OFF/ONV= 0 V ⎯ 0.01 0.5 μA 1
Limited current ILIM
⎯ 0.9 1.1 1.3 A 3
High level inpu t voltag e VSH VIN = 1.8 V to 4.5 V, OFFON/ pin 0.75 ⎯ ⎯ V 1
Low level input voltag e VSL VIN = 1.8 V to 4.5 V, OFFON/ pin ⎯ ⎯ 0.25 V 1
High level input current ISH VIN = 1.8 V to 4.5 V, OFFON/ pin −0.1 ⎯ 0.1 μA 1
Low level input current ISL VIN = 1.8 V to 4.5 V, OFFON/ pin −0.1 ⎯ 0.1 μA 1
Soft-start time*5 tSS ⎯ 0.6 1.2 1.8 ms 2
*1. This is the guaranteed value measured with external parts shown in “Table 6 External Parts List” and with test
circuits shown in Figure 6. The operating start voltage varies largely depending on diode’s forward voltage. Perform
sufficient evaluation with actual applicati on.
*2. VOUT(S) can be set by the ratio of VFB value and the output volta ge setting res istors (RFB1, RFB2). For details, refer to “
External Parts Selection”.
*3. VFB(S) is a setting value for FB voltage.
*4. Power MOS FET ON resistance lar gel y var ies depen ding o n the VOUT voltage.
*5. This is when the VOUT voltage startups from the STU release voltage or more. The soft-start time largely varies
depending on the load current and the input voltage when the S-8363 Series startups from the STU release voltage
or less, because the S-8363 Series once enters the start-up mode. Refer to “ 2. Low voltage start-up” for STU
release voltage.
External Parts List When Measuring Electrical Characteristics
Table 6 External Parts List
Element name Symbol Constants Manufacturer Part number
Inductor L 2.2 μH TDK Corporation VLF302510
Diode SD
- TOSHIBA CORPORATION CRS08
Input capacitor CIN 1 μF TAIYO YUDEN Co., Ltd. EMK107B7105KA
Output capacitor COUT 10 μF TAIYO YUDEN Co., Ltd. LMK212BJ106KD
FB pin capacitor CFB 47 pF TA IYO YUDEN Co., Ltd. UMK10 5CH4 70JV
Output voltage setting resisto r 1 RFB1 68 kΩ ROHM Co., Ltd. MCR03 series
Output voltage setting resisto r 2 RFB2 15 kΩ ROHM Co., Ltd. MCR03 series