S-8335A160FT-TB-G Seiko Instruments, S-8335A160FT-TB-G Datasheet - Page 12

• Manufacturer Part Number: S-8335A160FT-TB-G
• Description: IC REG SW 3CH STEP UP 24-TSSOP
• Manufacturer: Seiko Instruments
• Type: Step-Up (Boost), Invertingr

Specifications of S-8335A160FT-TB-G

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 7.48 ~ 13.93 V, -5.44 ~ -10.13 V
• Frequency - Switching: 100kHz
• Voltage - Input: 2.4 ~ 5 V
• Operating Temperature: -20°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 24-TSSOP
• Power - Output: 650mW
• Output Voltage: 13.93 V
• Operating Temperature Range: - 20 C to + 70 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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STEP-UP, FOR LCD BIAS SUPPLY, 3-CHANNEL SWITCHING REGULATOR
S-8335 Series
Operation
The S-8335 Series has two step-up type and one inverter type CMOS on-chip switching regulators. These
switching regulators employ the pulse frequency modulation (PFM) method to provide low current
consumption features.
1. Operation Overview
The output of the reference voltage generation circuit is the input to regulator S. The output of regulator
S is the input to regulator T. After the extremely steep rise has been blunted by an RC low-pass filter,
the output of regulator T becomes the DC/DC P reference voltage. The DC/DC P output (pin name:
VOUT1) that is controlled by the electric volume is obtained based on this reference voltage. The
DC/DC P output becomes the common driver positive power supply (VRH).
VRH is divided by internal resistors and becomes the input of OP amplifier X. The output (pin name:
VXO) of OP amplifier X becomes the segment driver positive power supply (VCH).
Also, the input voltage of OP amplifier X becomes the reference voltage of the DC/DC U error amplifier.
The DC/DC U output (pin name: VOUT3) is obtained so that it becomes 1.05 times larger than this
reference voltage. The DC/DC U output voltage can be used for the OP amplifier X power supply
voltage.
VCH is divided by internal resistors and becomes the input of OP amplifier Y. The output (pin name:
VYO) of OP amplifier Y becomes the segment driver intermediate potential (VM).
VM becomes the reference voltage of the DC/DC Q error amplifier. DC/DC Q oscillates and VRL is
obtained so that the common driver negative power supply (VRL) and VRH are symmetric around VM.
Seiko Instruments Inc.
Rev.6.0
_01