Only For Training And Service Purposes - LG TU550 Service Manual

4. 5. 3 Checking UMTS PAM Control Block
• PAM control signal
1. HDET_EN : UMTS Tx Power Detect IC(U1014:HDET) Enable
2. TX_AGC_ADJ : UMTS RTR6250 Tx Amp Gain Control
3. VREG : UMTS PAM enable
UMTS 850 Coupler
UMTS 1900 Couplar
VREG_UMTS 1900
VREG_UMTS 850
→ 62HDET_EN must be high (over 2.75V)
→ VREF must be high (over 2.85V)
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Only for training and service purposes

4. TROUBLE SHOOTING
UMTS Dual
PAM
- 81 -
LGE Internal Use Only