SC643EVB SEMTECH [Semtech Corporation], SC643EVB Datasheet
SC643EVB
Related parts for SC643EVB
SC643EVB Summary of contents
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POWER MANAGEMENT Features Input supply voltage range — 2.9V to 5.5V Very high effi ciency charge pump driver system with three modes — 1x, 1.5x, and 2x Five programmable current sinks with 29 increments from 0mA to 25mA Four programmable ...
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... JA Marking Information 643 yyww xxxx yyww = Date Code xxxx = Semtech Lot No. Ordering Information Device SC643ULTRT SC643EVB 16 Notes: LDO1 15 (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Lead-free packaging only. Device is WEEE and RoHS compliant, LDO2 14 and halogen free. BYP ...
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Absolute Maximum Ratings IN, OUT ( ...
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Electrical Characteristics (continued) Parameter Charge Pump Electrical Specifi cations (Cont.) 1.5x Mode to 2x Mode Falling Transition Voltage 2x Mode to 1.5x Mode Hysteresis Current Sink Off -State Leakage Current Pump Frequency LDO Electrical Specifi cations LDO1, LDO3, and LDO4 ...
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Electrical Characteristics (continued) Parameter Digital I/O Electrical Specifi cations (SPIF, ENL4) (8) Input High Threshold (8) Input Low Threshold Input High Current Input Low Current SemPulse Electrical Specifi cations (SPIF) (9) SemPulse Start-up Time Bit Pulse Duration (8) Duration Between ...
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Typical Characteristics Battery Current (5 LEDs) — 25mA Each V = 3.65V 125mA, 25°C OUT OUT 200 180 160 140 120 100 3.9 4.2 3.6 V (V) IN Battery Current (5 LEDs) — 12mA Each V = 3.45V, ...
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Typical Characteristics (continued) PSRR vs. Frequency — 1.8V V =3.7V, V =1.8V 50mA IN OUT OUT 0 -10 -20 -30 -40 -50 -60 -70 10 100 Frequency (Hz) Line Regulation (LDO2 1mA 1.2V to ...
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Typical Characteristics (continued) Load Regulation (LDO2) V =3.6V, 25° 1.2V -10 -15 -20 - (mA) LDO LDO Load Transient Response (3.3V) V =3.7V, V =3.3V 100mA, 25°C IN LDO LDO ...
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Typical Characteristics (continued) Ripple — 1X Mode V =3.8V, 5 Backlights — each, 25° (50mV/div (100mV/div) OUT I (20mA/div) BL Time (20μs/div) Ripple — 2X Mode V =2.9V, 5 Backlights — each, ...
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Pin Descriptions Pin # Pin Name PGND 3 BL3 4 BL2 5 BL1 6 BL4 7 BL5 8 ENL4 9 AGND 10 LDO4 11 LDO3 12 SPIF 13 BYP 14 LDO2 15 LDO1 16 OUT 17 C2+ ...
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Block Diagram SPIF 12 SemPulse Digital Interface and Logic Control LDO BYP 13 Voltage Reference 2 PGND AGND 9 8 ENL4 C2+ C1+ C1- C2 Fractional Charge Pump (1x, 1.5x, 2x) Oscillator ...
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Applications Information General Description This design is optimized for handheld applications sup- plied from a single cell Li-Ion and includes the following key features: • A high effi ciency fractional charge pump that supplies power to all LEDs • Five ...
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Applications Information (continued) Backlight Quiescent Current The quiescent current required to operate all fi ve back- lights is reduced when backlight current is set to 4.0mA or less. This feature results in higher effi ciency under light- load conditions. Further ...
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Applications Information (continued) Table 1 — Fade-In from Off State Command Action Sequence 1. Disable fade for Write to register 09h the bank 2. Set the bank to Write to register 01h (1) 0.5mA and/or 02h 3. Enable fade Write ...
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Applications Information (continued) Shutdown Mode The device is disabled when the SPIF pin is held low for the shutdown time specifi ed in the electrical characteris- tics section. All registers are reset to default condition at shutdown. Typical current consumption ...
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Applications Information (continued) PCB Layout Considerations The layout diagram in Figure 2 illustrates a proper two- layer PCB layout for the SC643 and supporting components. Following fundamental layout rules is critical for achieving the performance specified in the Electrical Characteristics ...
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SemPulse Interface Introduction SemPulse is a write-only single wire interface. It provides access registers that control device functional- ity. Two sets of pulse trains are transmitted to generate a complete SemPulse command. The fi rst ...
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SemPulse Interface (continued) SemPulse Timing Diagrams The SemPulse single wire interface is used to enable or disable the device and confi gure all registers (see Figure 5). The timing parameters refer to the digital I/O electrical specifi cations. SPIF ...
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Register Map (2) Address D5 D4 (3) 00h 0 BL5EN (3) 01h 0 MBL4 02h 0 (3) SBL4 (3) (3) 05h 0 0 06h 0 (3) 0 (3) (3) (3) 07h 0 0 08h 0 (3) 0 (3) 09h ...
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Register Map (continued) MBL4 through MBL0 [D4:D0] These bits are used to set the current for the main back- light current sinks. All enabled current sinks will sink the same current as shown in Table 4. Table 4 — Main ...
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Register Map (continued) SBL4 through SBL0 [D4:D0] These bits are used to set the current for the sub backlight current sinks. All enabled current sinks will sink the same current as shown in Table 5. Table 5 — Sub Backlight ...
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Register Map (continued) LDO2 Control Register (06h) This register is used to enable LDO2 and set its output voltage level. Bits [D5:D3] These bits are unused and are always zeroes. LDO2V2 through LDO2V0 [D2:D0] These bits are used to set ...
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Register Map (continued) LDO4 Control Register (08h) This register is used to enable LDO4 and set its output voltage level. The ENL4 pin must be high for register 08h to control LDO4. ENL4 has a logical AND function with the ...
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Register Map (continued) SFADE1 and SFADE0 [D5:D4] These bits are used to set the rise/fall rate between two backlight currents for the sub display as show in Table 11. For the fade feature to be active, the SFADE bit must ...
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Outline Drawing — MLPQ-UT-20 3x3 A PIN 1 INDICATOR (LASER MARK) A aaa NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE ...
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Land Pattern — MLPQ-UT-20 3x3 NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE ...