SC805AMLTRT – Complete Datasheet Summary
(Information extracted from Semtech SC805A.pdf, June-2008)

1. Device Overview1.1 Product NameSC805A – Miniature Integrated High-Current Li-Ion Battery Charger
2. 1.2 Ordering Code Highlighted
   SC805AMLTRT
   • Package: MLP-10 (3 mm × 3 mm)
   • Shipping: 3 000 pieces / tape-and-reel
   • RoHS / WEEE fully compliant, lead-free
3. 1.3 Key One-Line Description
   A stand-alone 1-A single-cell Li-Ion/Li-Poly switch-mode charger with integrated power FET, sense resistor, reverse-blocking diode and thermal protection, operable also as an LDO or programmable current source.
4. Feature Summary• 100 % integrated charger – no external FET, diode or sense resistor required• Tiny thermally-enhanced 10-lead 3 × 3 mm MLP (exposed pad)• 3 V – 6 V input range (ideal for 5 V USB/adapter)• Up to 1 A programmable fast-charge current (patented chopped-current sense, US 6,836,095)• 1 % voltage accuracy (4.16 V – 4.24 V over temp)• CC-CV profile with safety timers• Pre-charge trickle (10-125 mA) and programmable termination (10-125 mA)• Automatic recharge when VBAT falls 100 mV• NTC thermistor input (hot/cold) & battery-present (NOBAT) detection• LDO mode – works as regulated supply even when battery removed• Soft-start, UVLO, OVP, over-current, die-temperature (150 °C) and pre-charge timeout protection• <1 µA battery drain in shutdown/monitor• Dual LED status driver (CHRGB) – charging vs. complete/fault blinking• Auxiliary bias pin VCCIL (≈ VIN) to power external loads
5. Typical Applications• Cellular phones, smart-phones• PDAs, GPS, handheld meters• Digital still cameras, Bluetooth headsets• USB charging cradles / power banks• Programmable NiCd/NiMH or general current source
6. Pin-out & Pin Functions (MLP-10)1 VCC – adapter supply input2 VCCIL – low-drop copy of VCC to feed accessories (load current reduces charge current)3 VOUT – battery/regulated output4 IPRGM – fast-charge current set resistor to GND (RPRGM)5 ITERM – pre-charge & termination current set resistor to GND (RTERM)6 GND – ground & thermal pad7 EN/NTC – enable (low = off) / NTC thermistor input8 NOBAT – open-drain “battery removed” flag (high when NTC > 95 %VCC)9 RTIME – charge timer resistor; tie to GND = disable timer, tie to VCC = select LDO mode10 CHRGB – dual-colour LED driver (low = charging, high = complete, Hi-Z/blink = fault)T Exposed pad – solder to ground plane with multiple thermal vias
7. Absolute Maximum RatingsVCC, VCCIL, EN/NTC to GND ............... –0.3 V → 7 VVOUT, NOBAT, IPRGM, CHRGB, ITERM, RTIME .. –0.3 V → 6 VPeak reflow temperature ................... 260 °C (20-40 s)Junction temperature ...................... 150 °CStorage ................................... –65 °C → 150 °CContinuous output short ................. indefiniteMax total output current (VCCIL + VOUT) ... 1 AThermal resistance θJA (4-layer JEDSD51 PCB) 40 °C/W
8. Electrical Characteristics (VCC = 4.75 V, TJ = 25 °C unless noted)Input voltage operating .................. 3.5 V – 5.9 VQuiescent– shutdown (EN = low) ............... 0.1 µA typ (1 µA max)– charging ........................... 1.2 mA typ (1.55 mA max)Battery leakage (VCC = 0 V) ............. 0.1 µA typ (1 µA max)Regulated output (VBAT) ................. 4.20 V ±1 % (4.16-4.24 V)Fast-charge current (RPRGM = 1.87 k) .... 787 mA typ (91.5 % – 111.5 %)Pre-charge / termination (RTERM = 3.01 k) 50 mA typDrop-out (IOUT = 750 mA) ................ 250 mV typRecharge threshold ...................... VBAT – 100 mVTimer (RTIME = 39.2 k) ................. 2.5 h typ (2-3 h)OVP thresholds .......................... 6.8 V rising / 6.4 V falling (375 mV hys)UVLO .................................... 2.8 V rising / 2.75 V fallingNTC disable window ...................... <30 %VCC hot, >75 %VCC cold (50 mV hys)NOBAT level ............................. >95 %VCCDie thermal shutdown .................... 150 °C (10 °C hys)
9. Typical Operating Curves (selected)• CC/CV battery profile: 50 mA pre-charge → 0.8 A fast → 50 mA termination• Fast-charge accuracy ±2 % line/load 4.3-6 V• Drop-out resistance 0.25 Ω (VCC = 5 V)• Current limit fold-back when VCC < 4.2 V
10. Functional Flow / State Diagram Highlights
11. Plug-in → UVLO check → soft-start
12. VBAT < 2.8 V → pre-charge (timer quarter-limit)
13. VBAT > 2.8 V → constant-current (IPRGM)
14. VBAT = 4.2 V → constant-voltage until I < ITERM
15. Timer expires OR I < ITERM → monitor mode (off, 1 µA)
16. Re-charge when VBAT drops 100 mV or EN/VCC toggledFaults (OV, UV, NTC, die hot, pre-charge timeout) suspend charge and blink/status LED.
17. Setting External ComponentsFast-charge: IFAST (mA) = 1500 / RPRGM (kΩ)Pre-charge/termination: ITERM (mA) = 150 / RTERM (kΩ)Timer: TCHARGE (h) = 2.5 h × (RTIME / 39.2 kΩ) (1-10 h range)NTC divider (example for 0 °C / 50 °C with 10 k NTC): R2 = 9.53 k, RT1 = 10 k
18. PCB Layout Advice• Use Kelvin sense from battery – to GND pin; keep high-current paths wide and short• Place 0.1-2.2 µF ceramic at adapter input and battery output as close as possible to pins• Thermal pad: one large central via plus array of 0.3 mm vias to bottom ground plane ≥ 1 in² copper• Maintain < 50 mm total loop length for switching spikes; avoid vias in series with VOUT
19. Evaluation BoardSC805AEVB – populated reference design with dual-LED indicators, NTC network, USB/adapter jacks and test points.
20. Package Outline & Land PatternMLPD-10 3 mm × 3 mm, 0.5 mm pitch, 0.8 mm max height, exposed pad 2.1 mm × 2.1 mm. Exact land and stencil data provided in datasheet.