LG HT552TH Service Manual page 38

3) Flash R/W enable signal during download(Downloading)
2. SDRAM CLOCK
1) ES8381 main clock is at 27MHz(X501)
FIG 1-4
DCLK = 93MHz, Vp-p=2.2, Vmax=2.7V
FIG 2-1
3-11
FRD(IC503 PIN 28)
FWR(IC503 PIN 11)
(IC502 PIN 38)