Specifications
| Type | Description |
|---|---|
| Part Number | LM53603 |
| Manufacturer | Texas Instruments |
| Product Type | LDO Regulator |
| Category | Power Management |
| Package / Case | 16-lead HTSSOP (PWP), 5.00 mm x 4.40 mm x 1.00 mm nominal |
| Component Type | Power_IC |
| Maximum Load Current | 3 A; LM53603 |
| Input Voltage Range | 3.5 V to 36 V; operating input range described in features |
| Input Voltage Transient Tolerance | 42 V; input transient tolerance |
| Adjustable Output Voltage Range | 3.3 V to 10 V; adjustable output option |
| Switching Frequency | 2.1 MHz; fixed switching frequency |
| Output Voltage Tolerance | ±2%; feature specification |
| Junction Temperature Range | -40°C to 150°C; operating junction temperature range |
| Shutdown Current | 1.7 µA typ; typical shutdown current |
| Input Supply Current at No Load | 24 µA typ; no-load operation |
| Output Voltage | Adjustable; device comparison table, LM53603AMPWPR and LM53603AMPWPT |
| Package Quantity | 2000; LM53603AMPWPR |
| Package Quantity | 250; LM53603AMPWPT |
| Recommended Input Voltage | 3.9 V min, 36 V max; TJ=-40°C to 150°C |
| Recommended Output Voltage Adjustment Range | 3.3 V min, 10 V max; ADJ option, TJ=-40°C to 150°C |
| Recommended Output Current | 0 A min, 3 A max; LM53603, TJ=-40°C to 150°C |
| Recommended RESET Pin Current | 0 mA min, 1 mA max; TJ=-40°C to 150°C |
| Recommended Operating Junction Temperature | -40°C min, 150°C max; recommended operating conditions |
| VIN Absolute Maximum Rating | -0.3 V min, 40 V max; VIN to AGND/PGND; transient 42 V allowed for ≤500 ms at duty cycle ≤0.01% |
| EN Absolute Maximum Rating | -0.3 V min, 40 V max; EN to AGND/PGND; transient 42 V allowed for ≤500 ms at duty cycle ≤0.01% |
| CBOOT Absolute Maximum Rating | -0.3 V min, 3.6 V max; CBOOT to SW |
| BIAS Absolute Maximum Rating | -0.3 V min, 16 V max; BIAS to AGND/PGND |
| FB Absolute Maximum Rating | -0.3 V min, 5.5 V max; ADJ option, FB to AGND/PGND |
| RESET Absolute Maximum Rating | -0.3 V min, 8 V max; RESET to AGND/PGND |
| SYNC and FPWM Absolute Maximum Rating | -0.3 V min, 5.5 V max; SYNC/FPWM to AGND/PGND |
| VCC Absolute Maximum Rating | -0.3 V min, 4.2 V max; VCC to AGND/PGND |
| Storage Temperature | -40°C min, 150°C max; absolute maximum ratings |
| Junction-to-Ambient Thermal Resistance | 42.5 °C/W; PWP HTSSOP, 16 pins, JESD51-7 4-layer JEDEC board |
| Junction-to-Case Top Thermal Resistance | 22.6 °C/W; PWP HTSSOP, 16 pins |
| Junction-to-Case Bottom Thermal Resistance | 1.1 °C/W; PWP HTSSOP, 16 pins |
| Reference Voltage | 0.993 V min, 1.000 V typ, 1.007 V max; ADJ option, VIN=3.8 V to 36 V, FPWM, TJ=25°C |
| Reference Voltage | 0.990 V min, 1.000 V typ, 1.010 V max; ADJ option, VIN=3.8 V to 36 V, FPWM, TJ=-40°C to 125°C |
| Minimum Input Voltage to Operate | 3.2 V min, 3.95 V max; rising threshold |
| Minimum Input Voltage to Operate | 2.9 V min, 3.55 V max; falling threshold |
| Input Operating UVLO Hysteresis | 0.34 V typ; below minimum input operating voltage |
| Operating Quiescent Current | 8 µA typ, 13 µA max; measured at VIN pin, VBIAS=5 V, TJ=-40°C to 125°C |
| Shutdown Quiescent Current | 1.7 µA typ; measured at VIN pin, EN≤0.4 V, TJ=25°C |
| Shutdown Quiescent Current | 3.5 µA typ; measured at VIN pin, EN≤0.4 V, TJ=125°C |
| BIAS Pin Current | 47 µA typ, 78 µA max; VBIAS=5 V, FPWM=3.3 V |
| EN Pin Current | 2.3 µA typ; VIN=VEN=13.5 V |
| FB Pin Bias Current | 10 nA typ; ADJ option |
| RESET Upper Threshold Voltage | 105% min, 107% typ, 110% max; rising, percentage of nominal VOUT |
| RESET Lower Threshold Voltage | 92% min, 94% typ, 96.5% max; falling, percentage of nominal VOUT |
| RESET Hysteresis | 1.5% typ; as percent of output voltage setpoint |
| Enable Input Threshold Voltage | 1.7 V typ, 2.0 V max; rising threshold |
| Enable Input Threshold Hysteresis | 0.45 V min, 0.55 V typ; below enable rising threshold |
| Enable Full Shutdown Threshold | 0.8 V max; falling EN input voltage required for complete shutdown |
| Logic Input High Level | 1.5 V min; FPWM and SYNC pins |
| Logic Input Low Level | 0.4 V max; FPWM and SYNC pins |
| High-Side Switch Current Limit | 4.5 A min, 6.2 A typ; LM53603 |
| Low-Side Switch Current Limit | 3.0 A min, 3.6 A typ, 4.3 A max; LM53603 valley current limit |
| Datasheet Status | request_only |
Product Overview
The LM53603 is a Texas Instruments synchronous step-down buck converter categorized under Power_Management. It provides up to 3 A output current from an operating input range of 3.5 V to 36 V, with recommended VIN limits of 3.9 V minimum and 36 V maximum. The adjustable output option covers 3.3 V to 10 V, uses a 1.000 V typical reference, and specifies ±2% output-voltage tolerance.
The device uses a fixed 2.1 MHz switching frequency and includes operating details for UVLO, enable thresholds, RESET thresholds, FPWM and SYNC logic levels, and high-side and low-side current limits. Current-related specifications include 24 µA typical input supply current at no load, 8 µA typical operating quiescent current under the stated BIAS condition, and 1.7 µA typical shutdown current at TJ=25°C.
Packaging is a 16-lead HTSSOP (PWP), 5.00 mm x 4.40 mm x 1.00 mm nominal. Thermal data includes 42.5°C/W junction-to-ambient resistance, 22.6°C/W junction-to-case top resistance, and 1.1°C/W junction-to-case bottom resistance on the specified test conditions.
Key Features
- 3 A maximum load current for LM53603
- 3.5 V to 36 V operating input range
- 42 V input transient tolerance
- Adjustable 3.3 V to 10 V output option
- Fixed 2.1 MHz switching frequency
- ±2% output-voltage tolerance
- -40°C to 150°C junction-temperature operation
- 1.7 µA typical shutdown current
- 24 µA typical input supply current at no load
- RESET thresholds specified for output monitoring
- FPWM and SYNC logic input levels specified
- 16-lead HTSSOP PWP package
Typical Applications
- Adjustable DC output rails
- 3 A step-down regulation
- Wide-input voltage conversion
- No-load power rail operation
- RESET-monitored supply rails
- FPWM-controlled converter operation
- SYNC logic controlled power designs
- High-temperature junction environments
Procurement Notes
When requesting a quote for LM53603, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For power IC and power device sourcing, voltage rating, current rating, power dissipation, package thermal performance, protection features, qualification grade and application conditions should be reviewed before approval.
FAQ
What type of regulator is the LM53603?
The LM53603 is a Texas Instruments synchronous step-down buck converter in the Power_Management category. It supports a 3 A load current and uses a fixed 2.1 MHz switching frequency.
What input voltage range does the LM53603 support?
The extracted datasheet facts list a 3.5 V to 36 V operating input range, with recommended operating conditions of 3.9 V minimum and 36 V maximum. Input transient tolerance is specified at 42 V.
What output range is available on the adjustable option?
For the adjustable output option, the LM53603 supports a 3.3 V to 10 V output adjustment range. The output voltage is listed as adjustable for LM53603AMPWPR and LM53603AMPWPT device entries.
What package is used for the LM53603?
The package is a 16-lead HTSSOP identified as PWP, with nominal dimensions of 5.00 mm x 4.40 mm x 1.00 mm. Thermal resistance values are specified for the PWP HTSSOP, 16-pin package.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: June 30, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.