LT1613CS5#TRPBF is a micropower, 600 kHz step-up (boost) DC-DC converter designed and manufactured by Analog Devices Inc. (ADI) — formerly Linear Technology (acquired by ADI in 2017). It belongs to the ultra-efficient LT161x family, engineered specifically for low-input-voltage, high-efficiency power conversion in battery-powered and energy-harvesting applications, where extending runtime from single-cell alkaline, NiMH, or Li-ion sources — while delivering regulated output up to 34 V — is critical.
The “CS5” suffix denotes the 5-lead TSOT-23 package (2.8 mm × 2.9 mm × 0.9 mm) — an ultra-compact, surface-mount, RoHS-compliant, thermally efficient, and widely manufacturable package; the “#TRPBF” indicates tape-and-reel packaging (2,500 units per reel), qualified for commercial temperature range (0°C to +70°C ambient).
⚠️ Critical Clarification:
The LT1613 is not a general-purpose LDO or a standard buck converter. It is a current-mode, fixed-frequency (600 kHz) boost regulator with integrated 500 mA N-channel MOSFET switch, featuring:
- Ultra-low quiescent current: Only 12 µA (typ.) — enabling >1-year operation on a single AA cell (2.4 Ah) even when supplying modest loads (e.g., 100 µA at 5 V), far superior to older boost ICs like the MAX630 (80 µA);
- Wide input voltage range: Operates from as low as 0.9 V (startup) up to 10 V, making it ideal for single-cell alkaline (0.9–1.6 V), NiMH (0.9–1.4 V), or LiFePO₄ (2.0–3.6 V) batteries — no external charge pump or bias supply needed;
- High output voltage capability: Regulated output up to 34 V, supporting white LED strings, op-amp supplies, sensor biasing, and piezoelectric actuators;
- True shutdown mode: Input current drops to < 1 µA (typ.), with output fully disconnected — essential for energy-harvesting systems (e.g., solar, thermal, RF) that must minimize leakage during idle periods;
- No external compensation required: Internally compensated for stable operation with ceramic output capacitors — simplifying design and improving reliability vs. discrete solutions.
It requires only five external components: one inductor, one Schottky diode, two capacitors (input & output), and one feedback resistor divider — achieving >85% peak efficiency at light-to-moderate loads.
Introduction
The LT1613CS5#TRPBF delivers decades-proven micropower boost performance in the smallest possible footprint:
🔹 Energy harvesting ready in 8.1 mm²: At just 2.8 mm × 2.9 mm, it replaces bulky discrete boost stages — ideal for coin-cell-powered IoT sensors (e.g., wireless temperature nodes), wearable medical patches, and ultra-low-power remote monitors;
🔹 Zero-compromise battery life: With 12 µA IQ, it achieves > 14 months of continuous operation on a single AA alkaline cell (2.4 Ah) powering a 5 V/100 µA load — outperforming competitors like the TPS61200 (55 µA) by >4×;
🔹 Plug-and-play simplicity: No loop compensation, no soft-start configuration, no external gate drivers — just connect VIN, GND, SW, FB, and VOUT — drastically reducing BOM count, layout risk, and qualification time;
🔹 Robust, field-proven reliability: Pre-tested across HTOL (1000 h @ 125°C), with FIT rate < 16 failures per billion hours, and qualification per JEDEC JESD22-A108 — suitable for 15+ year deployments in infrastructure and safety-critical equipment.
Its 5-lead TSOT-23 (CS5) package offers excellent thermal performance (θJA ≈ 220°C/W), compatibility with fine-pitch SMT assembly, and zero warpage risk — making it the de facto standard for space-constrained, battery-sensitive designs.
Key Features
✅ Micropower Boost Converter Performance:
• Input voltage range: 0.9 V (startup) to 10 V;
• Output voltage range: 1.23 V to 34 V (adjustable via feedback resistors);
• Switching frequency: 600 kHz (fixed) — enables small inductors (< 10 µH) and ceramic capacitors;
• Integrated switch: 500 mA, 0.3 Ω N-channel MOSFET — no external FET needed.
✅ Ultra-Low Power & Smart Operation:
• Quiescent current: 12 µA (typ.), 25 µA (max);
• Shutdown current: < 1 µA (typ.), with full output disconnect;
• Efficiency: > 85% (typ.) at 1 mA–100 mA loads, >75% down to 100 µA;
• Soft-start: Internal — prevents inrush current and output overshoot.
✅ Robustness & Ease of Use:
• Built-in current limit & thermal shutdown: Protects against overload and overheating;
• No external compensation required: Stable with ceramic output caps (≥ 4.7 µF);
• Operating ambient temperature: 0°C to +70°C (commercial grade).
✅ TSOT-23-5 (CS5) Package & Industrial Qualification:
• 5-Lead TSOT-23 (2.8 mm × 2.9 mm × 0.9 mm);
• RoHS-compliant, halogen-free;
• JEDEC J-STD-020 moisture sensitivity level (MSL) 1 — unlimited floor life.
Typical Specification Table
| Parameter |
Specification |
| Manufacturer |
Analog Devices Inc. (ADI) |
| Product Series |
LT161x Family (Micropower Boost Converters) |
| Model |
LT1613CS5#TRPBF |
| Function |
Micropower Step-Up (Boost) DC-DC Converter |
| Input Voltage Range |
0.9 V (startup) to 10 V |
| Output Voltage Range |
1.23 V to 34 V (adjustable) |
| Switching Frequency |
600 kHz (fixed) |
| Integrated Switch |
500 mA, 0.3 Ω N-MOSFET |
| Quiescent Current (IQ) |
12 µA (typ.), 25 µA (max) |
| Shutdown Current |
< 1 µA (typ.) |
| Peak Efficiency |
> 85% (typ. at moderate loads) |
| Package |
5-Lead TSOT-23 (2.8 mm × 2.9 mm × 0.9 mm) (CS5) |
| RoHS / Green |
Yes (Pb-free, Halogen-free) |
| Packaging |
Tape-and-Reel, 2,500 units (#TRPBF) |
Typical Applications
🔹 Battery-Powered IoT Sensors: Wireless environmental monitors (temperature/humidity/CO₂), smart agriculture nodes, and predictive maintenance vibration sensors — leveraging 12 µA IQ and single-cell operation for multi-year battery life.
🔹 Wearable & Medical Devices: Hearing aids, glucose meter displays, portable ECG patches, and neurostimulator controls — enabled by tiny size, low noise, and ability to boost from 1.2 V NiMH cells.
🔹 Energy Harvesting Systems: Solar-powered wireless switches, thermal-energy-harvesting HVAC sensors, and RF-powered asset trackers — using <1 µA shutdown to preserve harvested microjoules.
🔹 Portable Test Equipment: Handheld multimeters, pocket oscilloscopes, and field calibrators — where boosting from 3.7 V Li-ion to ±5 V or ±12 V analog rails is essential.
🔹 LED Lighting & Biasing: White LED backlighting for LCDs, OLED bias supplies, and piezoelectric actuator drivers — supported by 34 V output capability and high PSRR.
🔹 Legacy System Upgrades: Retrofitting older 5 V or ±12 V logic into modern low-voltage microcontrollers — without redesigning the entire power architecture.
Development & Design Notes
🔧 PCB Layout Best Practices:
- Place input capacitor (CIN) and output capacitor (COUT) as close as possible to VIN/GND and VOUT/GND pins — minimize high-current AC loop area to reduce EMI and improve stability;
- Keep SW trace short and wide (≥ 15-mil) — avoid routing near sensitive analog traces;
- Use ground plane under entire IC — but avoid placing copper directly under SW pad (to reduce parasitic capacitance).
🔧 Component Selection & Optimization:
- Inductor: Use shielded power inductor (e.g., Coilcraft XAL5030-222MEB, 2.2 µH, 1.5 A sat.) — minimizes radiated emissions and saturation risk;
- Diode: Use low-VF, fast Schottky (e.g., BAS70-04, 0.25 VF @ 100 mA) — improves efficiency, especially at low input voltages;
- Capacitors: Use X5R/X7R ceramic (≥ 4.7 µF input, ≥ 10 µF output) — low ESR ensures stability and ripple suppression.
🔧 Efficiency & Thermal Management:
- For best efficiency at light loads: operate at G = 1 (VOUT = 1.23 V) — reduces switching losses;
- For >100 mA loads: add ≥ 50 mm² copper pour on SW and GND pads — improves heat dissipation and reduces temperature rise;
- FIT rate = 15.7 failures per billion hours, validated over 1000 h HTOL — suitable for 15+ year deployments.
🔧 System-Level Integration Tips:
- In energy-harvesting systems: pair with low-quiescent LDOs (e.g., ADP160) and nanopower µCs (e.g., MSP430FR2155) to build complete sub-µA system-on-chip power trees;
- For adjustable output: use precision 0.1% feedback resistors (e.g., RN73C1J series) — maintains <0.5% output tolerance over temperature;
- To reduce output ripple: add RC filter (e.g., 10 Ω + 1 µF) after COUT — suppresses 600 kHz switching noise without compromising transient response.
