sc624a Semtech Corporation, sc624a Datasheet
sc624a
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sc624a Summary of contents
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... Enable Control C 22nF June 27, 2007 Description The SC624A is a high effi ciency charge pump LED driver using Semtech’s proprietary mAhXLife Performance is optimized for use in single-cell Li-ion battery applications. The charge pump provides backlight current in conjunction with four matched current sinks. The load and supply conditions determine whether the charge pump operates in 1x, 1 ...
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... Date Code xxxx = Semtech Lot No. Ordering Information Device SC624AULTRT SC624AEVB Notes: 16 (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Available in lead-free package only. Device is WEEE and RoHS 15 LDO1 compliant. 14 LDO2 13 BYP EN 12 SDA 11 10 SC624A Package (1)(2) MLPQ-UT-20 3×3 Evaluation Board 2 ...
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... Charge pump in 1.5x mode, 4 backlights on Charge pump in 2x mode, 4 backlights on I VOUT pin shorted to GND OUT(SC) T OTP (2) = 3.0V to 4.2V 2.2μ Min Typ 0.1 100 220 < 200mA LDO 3.8 4.6 4.6 300 160 SC624A < +85 A < 5.5 IN < 5.25 OUT (°C/ Max Units 2 μA 160 μA 340 4.65 5.85 mA 5.85 mA °C 3 ...
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... LDO1 1mA, V LDO1 ΔV LINE LDO2 1mA, V LDO2 Min Typ = V OUT OVP 5.3 5.7 2.4 IN 300 100 0.5 = 25°C -8 ±1.5 A (2) -3.5 ±0.5 = 3.2V 3.27 OUT = 3.2V 250 OUT (3) = 4.0V 2.92 OUT (3) = 4.0V 300 OUT 0.1 250 2.5 1.5 = 1mA -3.5 ±3 = 2.8V 2.1 OUT = 1.8V 1.3 OUT SC624A Max Units 6 +3 μA kHz 3.3 V 1.8 V +3.5 % 7.2 mV 4.8 4 ...
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... I B-IN V HYS t SP Min Typ = 3.7V, = 3.7V, 100 200 = 22nF 50mA, LDO1 50 ripple P-P = 50mA, LDO2 60 ripple P-P = 22nF 1μF, LDO 100 < 3V LDO1 = 22nF, BYP 1.6 -0.2 0.1 50 SC624A Max Units 150 μV RMS μ μA +1 μA 0 0.4 V 0.2 μ ...
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... HD_STA t SU_STO t BUF t Bus Start-up Time After EN Pin is Pulled High BL(MAX) BL(MIN) drops 100mV from nominal. Dropout does not apply to LDO2 since it has a maximum output voltage LDO1 SC624A Min Typ Max Units 10 pF 400 440 kHz 1.3 μs 0.6 μs 0 μs 100 μ ...
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... Backlight Effi ciency (4 LEDs) — 12mA Each V OUT 100 4.2 3.4 3.2 3.0 Backlight Effi ciency (4 LEDs) — 5.0mA Each V OUT 100 3.4 3.2 3.0 4.2 SC624A Battery Current (4 LEDs) — 12mA Each =3.50V, I =48mA, 25°C OUT 4.0 3.8 3.6 3.4 V (V) IN =3.50V, I =48mA, 25°C OUT 4.0 3.8 3.6 3.4 V (V) IN =3.33V, I =20mA, 25°C OUT 4.0 3 ...
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... I (mA) LDO1 0 -10 -20 -30 -40 -50 -60 -70 10000 1000 100 100 PSRR vs. Frequency (LDO2) V =3.7V at 25°C, I =50mA, V =1.8V IN LDO2 LDO2 10 100 1000 Frequency (Hz) Noise vs Load Current (LDO2) V =1.8V, V =3.7V, 25°C LDO2 (mA) LDO2 SC624A 10000 100 80 8 ...
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... Line Regulation (LDO1) V =2.8V, I =1mA, 25°C LDO1 LDO1 4.2 4.0 3.8 3 -16 -24 90 120 150 3.4 3.2 3.0 4.2 Load Regulation (LDO2) V =1.8V, V =3.7V, 25°C LDO2 (mA) LDO2 Line Regulation (LDO2) V =1.8V, I =1mA, 25°C LDO2 LDO2 4.0 3.8 3.6 3.4 V (V) IN SC624A 120 150 3.2 3.0 9 ...
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... Time (20μs/div) Load Transient Response (LDO2) — Falling Edge V =3.7V, V =1.8V, I =100 to 1mA IN LDO2 LDO2 V (50mV/div) LDO2 I (100mA/div) LDO2 Time (200μs/div) Output Open Circuit Protection V =3.7V, 25° (500mV/div) BL1 V (2V/div) OUT I (20mA/div) BL1 Time (200μs/div) SC624A 10 ...
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... Battery voltage input — connect with a 1μF capacitor to PGND Negative connection to bucket capacitor 1 — requires a 1μF capacitor connected to C1+ Thermal pad for heatsinking purposes — connect to ground plane using multiple vias — not connected internally SC624A — leave this pin open if unused — ...
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... C1+ C1- C2+ C2 mAhXLife Fractional VIN Charge Pump (1x, 1.5x, 2x) Oscillator Compatible Interface and Logic Control Current Setting DAC Bandgap Reference Voltage Setting DAC SC624A VOUT 16 VOUT 2 PGND 4 BL1 5 BL2 6 BL3 7 BL4 3 NC VIN LDO1 15 LDO1 VIN LDO2 14 LDO2 12 ...
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... For backlight applications using less than four LEDs, any unused output must be left open and the unused LED driver must remain disabled. When writing to the Backlight Enable Control register, a zero written to the corresponding bit of any unused output. SC624A 2 C compatible ) F (0) ...
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... All device functions can be controlled via the I compatible interface. The interface is described in detail in the Serial Interface section of the datasheet. Protection Features The SC624A provides several protection features to safeguard the device from catastrophic failures. These features include: • Output Open Circuit Protection • ...
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... OVP condition from occurring due to the resulting open loop. Float detect ensures device protection but does not ensure optimum performance. Unused LED outputs must be disabled to prevent an open circuit fault from occurring. SC624A 15 ...
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... Applications Information (continued) PCB Layout Considerations The layout diagram in Figure 1 illustrates a proper two-layer PCB layout for the SC624A and supporting components. Following fundamental layout rules is critical for achieving the performance specifi ed in the Electrical Characteristics table. The following guidelines are recommended when developing a PCB layout: • ...
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... The longest elapsed time 32 for a full scale fade-out of the backlight is nominally 1.024 seconds when the default interval of 32ms is used Reset Value BL_2 BL_1 BL_0 0x00 BLEN_2 BLEN_1 0x00 LDO1_1 LDO1_0 0x00 SC624A Description Backlight Current Control Backlight Enable Control LDO Control 17 ...
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... BLEN_3 — Enable bit for backlight BL3 0.5 BLEN_2 — Enable bit for backlight BL2 1.0 BLEN_1 — Enable bit for backlight BL1 1.5 2.0 When enabled, the current sinks will carry the current set 2.5 by the backlight current control bits BL[4:0], as shown in Table 1. 3.0 3.5 4.0 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10 SC624A 18 ...
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... These bits set the output voltage of LDO1, as shown in Table 3. LDO1_3 LDO2 0 Output Voltage 0 OFF 0 1.8V 0 1.7V 0 1.6V 1.5V 1 OFF 1 1010 through 1111 are not used SC624A Table 3 — LDO1 Control Bits LDO1_2 LDO1_1 LDO1_0 ...
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... After performing other tasks, the master can send a start or restart condition to the SC624A with a read command. The device acknowledges this request and returns the data from the register location that had previously been set up ...
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... Slave Address B S Slave Address – 7-bit Register address – 8-bit Data – 8-bit A Sr Slave Address Slave Address – 7-bit Register address – 8-bit Data – 8-bit A P Register Read Access S/Sr Slave Address R A Data NACK Data SC624A NACK P 21 ...
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... CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS . 3. DAP is 1.90 x 190mm SEATING PLANE C D1 LxN E/2 N D/2 bxN bbb SC624A DIMENSIONS INCHES MILLIMETERS DIM MIN NOM MAX MIN NOM MAX - - A .020 .024 0. .000 .002 ...
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... FUNCTIONAL PERFORMANCE OF THE DEVICE. Contact Information DIM Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com SC624A DIMENSIONS INCHES MILLIMETERS (.114) (2.90) .083 2.10 .067 1.70 .067 1.70 .016 0.40 .004 0.10 .008 0.20 .031 0.80 ...