Texas Instruments BQ500100DCKR

Overview

BQ500100DCKR from Texas Instruments is a high-side current-sense amplifier designed for foreign object detection (FOD) in wireless power transmitters. It features 50 V/V fixed gain, ±150 μV max offset voltage, 0 V to 20 V common-mode input range, and operates from 2.7 V to 6 V supply - enabling accurate shunt-based current monitoring on rails up to 19 V in Qi-compliant 5-W/15-W systems.

For engineers reviewing the BQ500100DCKR datasheet, BQ500100DCKR pinout, BQ500100DCKR application, or BQ500100DCKR equivalent, key selection criteria include its ability to measure current at common-mode voltages far exceeding its own supply rail, its low quiescent current (≤100 μA), SC70-6 package footprint, and guaranteed ±2% gain error over temperature for FOD-critical accuracy.

Technical Context

The BQ500100DCKR employs a proprietary high-voltage input stage that decouples common-mode input range (0–20 V) from supply voltage (2.7–6 V), allowing operation with coil supply rails up to 19 V while powered from a 3.3-V system rail. Its 120 dB typical CMRR ensures stable output under dynamic rail voltage modulation during power transfer.

It delivers 80-kHz bandwidth and 0.4 V/μs slew rate to track fast transient currents in resonant wireless charging topologies, while maintaining RTI voltage noise of 25 nV/√Hz and input bias current ≤28 μA across –40°C to +105°C - critical for low-drift FOD threshold detection.

Key Specifications

Pinout & Package

Package: SC70-6 (DCK), 2.00 mm × 1.25 mm body, 0.65-mm lead pitch, moisture sensitivity level 2 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side current-sense amplifier applications.

Compared with INA240A1D and bq500101DCKR, the BQ500100DCKR provides optimal balance of ultra-small SC70 footprint, rail-to-rail common-mode capability, and analog simplicity - making it ideal for cost-sensitive, space-constrained Qi transmitters where external MCU handles FOD computation.

Availability

BQ500100DCKR is available at Aetrix Electronics and suitable for wireless power transmitters, foreign object detection subsystems, and high-side current monitoring applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for BQ500100DCKR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company delivering analog and embedded processing solutions, with leadership in power management, signal chain, and wireless connectivity technologies.

The BQ500100DCKR belongs to TI's wireless power transmission analog front-end product line, engineered specifically to enable reliable, standards-compliant foreign object detection in compact, thermally constrained Qi transmitter designs.

FAQ

What is the maximum common-mode voltage the BQ500100DCKR can handle?

The BQ500100DCKR supports a common-mode input voltage range of 0 V to 20 V, with absolute maximum ratings allowing up to 26 V on IN+ and IN− pins. This enables direct sensing on 19-V wireless power rails while powered from a 3.3-V supply - a key enabler for single-supply FOD architectures without level-shifting circuitry. The BQ500100DCKR maintains specified performance across this full range.

Does the BQ500100DCKR require power supply sequencing with the sensed rail?

No - the BQ500100DCKR has no power sequencing requirement. Voltages may be present on IN+ and IN− pins before V+ is applied, due to its internal topology. This eliminates timing constraints between coil supply startup and sensor power-up, simplifying system initialization in wireless power transmitters. The BQ500100DCKR settles to valid output within ~50 μs after V+ is applied.

Can the BQ500100DCKR be used for bidirectional current sensing?

The BQ500100DCKR is specified and optimized for unidirectional high-side current sensing (IN+ to IN− current flow). While its input structure permits reverse polarity, the datasheet defines normal operation only for forward current, and gain/offset specs apply under that condition. For true bidirectional applications, TI recommends the bq500101DCKR or INA240-series devices explicitly characterized for bidirectional use. The BQ500100DCKR does not guarantee symmetric performance in reverse mode.

What is the recommended shunt resistor value for use with the BQ500100DCKR in a 1-A wireless charging application?

For a 1-A full-scale current with the BQ500100DCKR's 50 V/V gain and 10-mV full-scale shunt specification, a 20-mΩ shunt yields 20-mV differential drop and 500-mV output - matching typical ADC input ranges. At 1 A, this dissipates 20 mW, satisfying typical thermal constraints. The BQ500100DCKR's low offset (±150 μV) ensures <0.75% offset-induced error at this point, supporting the 2.3% total accuracy target cited in TI's reference design.

How does the BQ500100DCKR handle switching noise from the wireless power transmitter's DC-DC converter?

The BQ500100DCKR relies on external RC filtering (RF1/RF2 + CF per Figure 6) at the IN+/IN− inputs to attenuate high-frequency switching ripple. TI recommends Kelvin (4-wire) shunt connections and tight filter placement to minimize loop area. The device's 80-kHz bandwidth and 120-dB CMRR reject low-frequency rail modulation, but external filtering is mandatory for >100-kHz noise. The BQ500100DCKR's input bias current (≤28 μA) ensures minimal filter interaction, preserving accuracy.