Heart rate data collection

摘要

One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.

主权项

1. A circuit comprising:
a light detector for receiving light and for generating a first electrical signal based on the received light; a controller for generating one or more first control signals and one or more second control signals; a first switching circuit having at least a first configuration and a second configuration, the first switching circuit for:
receiving a first voltage signal based on the first electrical signal,receiving the one or more first control signals;switching among at least the first configuration and the second configuration based on the one or more first control signals; a first sampling circuit for sampling a value of the first voltage signal when the first switching circuit is in the first configuration; a second sampling circuit for sampling a value of the first voltage signal when the first switching circuit is in the second configuration; and an ambient light cancellation circuit for generating a first current signal to at least partially counter a first component of the first electrical signal when the first switching circuit is in the first configuration, the first current signal being based on the one or more second control signals and the value of the first voltage signal sampled by the second sampling circuit.