src/Derivation/Bip39/Bip39.php
public function mnemonicToSeedBytesWithErrorChecking($mnemonic, $passphrase = '')
    {
        // This will throw an exception if the embedded checksum is incorrect
        $this->mnemonicToEntropy($mnemonic);

        return $this->mnemonicToSeedBytes($mnemonic, $passphrase);
    }
public function mnemonicToSeedBytesWithErrorChecking($mnemonic, $passphrase = '')
    {
        // This will throw an exception if the embedded checksum is incorrect
        $this->mnemonicToEntropy($mnemonic);

        return $this->mnemonicToSeedBytes($mnemonic, $passphrase);
    }
Converts $mnemonic to seed bytes suitable for creating a new HDNode

If the mnemonic is invalid, an exception is thrown

@param        $mnemonic
@param string $passphrase
@return string raw bytes